At present, the prediction of PM_2.5 and its key secondary components in the atmospheric model shows large deviations from field measurements, which indicates that there are unknown mechanisms for the formation of secondary particles in the atmosphere. Based on laboratory simulation and field observation, we have revealed a new mechanism for the formation of secondary particles under the conditions of complex air pollution, and put forward the “haze chemistry” theory to explain the cause of complex air pollution in China. The main idea is that the oxidation capacity and the explosive growth of the transformation from gaseous pollutants to particulate pollutants increases under the conditions of complex air pollution. The decrease of environmental capacity has resulted in frequent haze pollution events in central and eastern China and made governance difficult. It is suggested that key pollutants such as SO₂, VOCs, NOx, black carbon and NH₃ should be controlled to improve the environmental capacity.

1. Pt/TiO₂ catalyst for ambient HCHO oxidation

For the first time in the world, we developed a highly efficient and stable Pt/TiO₂ catalyst for the catalytic oxidation of formaldehyde (HCHO), achieving complete catalytic decomposition of formaldehyde into H₂O and CO₂ at room temperature without any external energy input. It was clarified that highly dispersed Pt species on TiO₂ play the key role in determining the activity of the Pt/TiO₂ catalyst for ambient HCHO destruction, and the reaction mechanism of HCHO oxidation over the noble metal catalyst was elucidated. (Catal. Commun., 2005, 6, 211; Appl. Catal. B, 2006, 65, 37; Catal. Today, 2007, 126, 345)

2. Promotion effect of alkali metal ions and oxygen vacancies

It is observed that alkali metal ions have a significant promotion effect on the activity of Pt/TiO₂ for ambient HCHO oxidation. The Na-free catalyst had low activity for HCHO oxidation, with HCHO conversion being only ca. 19% at room temperature. With 2% Na addition, 100% HCHO conversion to CO₂ and H₂O was measured. It was revealed that the alkali metal ions significantly promote the activity of Pt/TiO₂ by inducing atomically dispersed Pt species, thereby opening a new low-temperature reaction pathway. (Angew. Chem. Int. Ed., 2012, 51, 9628）

We observed that Na doping also has a dramatic and common promotion effect on the Pd/TiO₂ and Ir/TiO₂ catalyst systems. It was revealed that Na species addition can facilitate the activation of H₂O and chemisorbed oxygen, therefore resulting in high performance for the Na doped Pd- and Ir-based catalysts for ambient HCHO destruction. In addition, the synergistic effect of H₂O and chemisorbed oxygen on HCHO oxidation was also illuminated. (Environ. Sci. Technol., 2014, 48, 5816; Catal. Sci. Technol., 2016, 6, 2289; Catal. Today, 2017, 281, 412; ACS Catal., 2018, 8, 11377)

We discovered the promotion effect of high temperature reduction on Pd/TiO₂ catalysts for HCHO oxidation. It was found that oxygen vacancies played vital roles in the abnormal phenomenon that high temperature reduction did not induce Pd aggregation, but rather enhanced Pd dispersion. The oxygen vacancies could not only trap the diffusing Pd particles but also facilitate the activation of H₂O and chemisorbed oxygen. The work applied a new concept to design catalysts with high dispersion of supported noble metals. (Appl. Catal. B, 2017, 217, 560)

3. Practical applications of Pt-based catalyst

We have successfully implemented this basic research achievement into practical applications. New Air Cleaners equipped with the novel Pt-based catalyst have been developed and put into the Chinese market, and have already become the best-selling Air Cleaner in China, greatly improving indoor air quality and benefitting the Chinese people.

Relevant publications

19. Xueyan Chen, Min Chen, Guangzhi He, Fei Wang, Guangyan Xu, Yaobin Li, Changbin Zhang*, Hong He, “Specific role of potassium in promoting Ag/Al₂O₃ for catalytic oxidation of formaldehyde at low temperature”, J. Phys. Chem. C., 122, (2018) 27331-27339.

18. Yaobin Li, Xueyan Chen, Chunying Wang, Changbin Zhang*, Hong He, “Sodium enhances Ir/TiO₂ activity for catalytic oxidation of formaldehyde at ambient temperature”, ACS Catal., 8, (2018) 11377-11385.

17. Yaobin Li, Changbin Zhang^*, Jinzhu Ma,Min Chen,Hua Deng, Hong He*, “High temperature reduction dramatically promotes Pd/TiO₂ catalyst for ambient formaldehyde oxidation”, Appl. Catal. B, 217, (2017) 560-569.

16. Yaobin Li, Changbin Zhang*, Hong He, “Significant enhancement in activity of Pd/TiO₂ catalyst for formaldehyde oxidation by Na addition”, Catal.Today,281, (2017) 412-417.

15. Yaobin Li, Changbin Zhang, Hong He*, Jianghao Zhang, Min Chen, “Influence of alkali metals on Pd/TiO₂ catalysts for catalytic oxidation of formaldehyde at room temperature”, Catal. Sci. Technol., 6(7), (2016) 2289-2295.

14. Jianghao Zhang, Yaobin Li, Yan Zhang, Min Chen, Lian Wang, Changbin Zhang*, Hong He, “Effect of support on the activity of Ag-based catalysts for formaldehyde oxidation”,Sci. Rep., 5, (2015) 12950.

13. Jianghao Zhang, Yaobin Li, Lian Wang, Changbin Zhang*, Hong He. “Catalytic oxidation of formaldehyde over manganese oxides with different crystal structure”, Catal. Sci. Technol., 5(4), (2015) 2305-2313.

12. 张江浩，王亚飞，张长斌*，贺泓，“负载方式对Ag/CoO₃催化剂催化氧化甲醛活性的影响”，化学工业与工程，32(3),(2015)67-72.

11. Changbin Zhang, Yaobin Li, Yafei Wang, Hong He*, “Sodium-promoted Pd/TiO₂ for catalytic oxidation of formaldehyde at ambient temperature”, Environ. Sci. Technol., 48, (2014) 5816-5822.

10. Changbin Zhang, Fudong Liu, YanpingZhai, Hiroko Ariga, Nan Yi, Yongchun Liu, Kiyotaka Asakura, Maria Flytzani-Stephanopoulos*, Hong He*, “Alkali metal promoted Pt/TiO₂ opens a more efficient pathway to formaldehyde oxidation at ambient temperatures”, Angew. Chem. Int. Ed.2012, 51(38) 9628-9632.

9. Li Zhou, Junhui He*, Jie Zhang, Zhicheng He, Yucai Hu, Changbin Zhang, and Hong He, “Facile in-situ synthesis of manganese dioxide nanosheets on cellulose fibers and their application in oxidative decomposition of formaldehyde”, J. Phys. Chem. C, 2011, 115, 16873-16878.

8. Ken-ichi Tanaka*, Masashi Shou, Hong He, Changbin Zhang, Daling Lu, “A CO-tolerant hydrogen fuel cell system designed by combining with an extremely active Pt/CNT catalyst”, Catal. Lett., 127, (2009) 148-151.

7. Hongwei Gao*, Tingxia Yan, Changbin Zhang, Hong He, “Theoretical and experimental analysis on vibrational spectra of formate species adsorbed on Cu-Al₂O₃ catalyst”, J. Mol. Struct. (THEOCHEM), 857, (2008) 38-43.

6. Hongmin Chen, Junhui He*, Changbin Zhang, Hong He, “Self-assembly of novel mesoporous manganese oxide nanostructures and their application in oxidative decomposition of formaldehyde”, J. Phys. Chem. C, 111, (2007) 18033-18038.

5. Changbin Zhang, Hong He*, “A comparative study of TiO₂ supported noble metal catalysts for the oxidation of formaldehyde at room temperature”, Catal. Today, 126, (2007) 345-350.

4. Changbin Zhang, Hong He*, Ken-ichi Tanaka, “Catalytic performance and mechanism of a Pt/TiO₂ catalyst for the oxidation of formaldehyde at room temperature”, Appl. Catal.B, 65, (2006) 37-43.

3. Xiaoyan Shi, Changbin Zhang, Hong He, Masashi Shou, Ken-ichi Tanaka*, Shinichi Sugihara, Yoshitaka Ando, “Activation of Pt/TiO₂ catalysts by structural transformation of Pt-sites”, Catal. Lett., 107(1-2), (2006) 1-4.

2. Changbin Zhang, Xiaoyan Shi, Hongwei Gao, Hong He*, “The elimination of formaldehyde over Cu-Al₂O₃ at room temperature”, J. Environ. Sci., 17, (2005) 429-432.

1. Changbin Zhang, Hong He*, Ken-ichi Tanaka, “Perfect catalytic oxidation of formaldehyde over a Pt/TiO₂ catalyst at room temperature”, Catal. Commun., 6, (2005) 211-214.

We have developed a series of Pd-based catalysts with both adsorption capacity and catalytic activity for removal of BTX. By using a Pd/AC catalyst, we established an adsorption in situ catalytic oxidation method for indoor air BTX removal, which simplifies the traditional method “adsorption – desorption – oxidation” to an “adsorption – in situ oxidation” process. The ordered mesoporous Pd/Co₃O₄ (3D) catalyst with more-ordered mesostructure and more well-dispersed PdO species shows excellent activity for o-xylene oxidation. Nanosized CeO₂ particles, cubes, and rods are highly active for catalytic oxidation of o-xylene, and are comparable with traditional noble-metal catalysts, in which oxygen vacancy clusters play key role in the oxidation process. These catalysts are potential materials for removal of VOCs at low temperature. (Appl. Catal. B, 2013, 142-143, 72; Catal. Sci. Technol., 2016, 6, 4840; Sci. Rep., 2017, 7, 12845）

2. Removal of BTX by the combination of non-thermal plasma and catalysis

The effects of different precursors and loading amounts of Mn in the preparation of Mn/Al₂O₃ catalysts for use in plasma-catalytic removal of o-xylene were systematically investigated. Results showed that Mn/Al₂O₃ catalysts could efficiently improve o-xylene conversion with low specific energy density. _.A Mn/Al₂O₃ catalyst prepared with a manganese acetate precursor was found to have excellent catalytic activity for o-xylene removal, with reduced formation of O₃ and NO_x byproducts. More Mn⁴⁺ species, richer lattice oxygen and the presence of the MnO₂ microcrystal phase on the surface of the catalyst were responsible for the high catalytic activity in the oxidation of o-xylene.  (Chem. Eng. J., 2016, 288, 406; J. Phys. Chem. C, 2016, 120, 6136)

3. Oxidation of BTX by electro-catalysis technology

We report, for the first time, a facile gas-solid interface electrochemical oxidation method for the mineralization of benzene compounds at ambient temperature. A membrane electrode assembly (MEA) was used in an all-solid cell. The activity test results showed that 100% benzene compound conversion to CO₂ (85–99%) and CO (15–1%) was achieved at the optimal cell voltage of 2.0 V at relative humidity 60%. Proton-transfer-reaction time-of-flight mass spectrometry and Fourier transform infrared spectroscopy results showed that no organic byproducts could be detected in the anodic reservoir. The electrochemical behavior of the working electrode in benzene solutions with different concentrations revealed that the benzene oxidation process was mainly an indirect oxidation process at the onset potential of OER (2.0 V vs Ag/AgCl, saturated KCl). Our findings provide evidence that the gas-solid interface electrochemical oxidation method has potential as a method for ambient VOC destruction in indoor air environments.  (Chem. Eng. J., 2018, 354, 93; Chemosphere,2019,217, 780)

Relevant publications

24. Hua Deng, Shunyu Kang, Jinzhu Ma*, Lian Wang, Changbin Zhang, Hong He, “Role of structural defects in MnOx promoted by Ag doping in the catalytic combustion of volatile organic compounds and ambient decomposition of O₃”, Environ. Sci. Technol., 53, (2019) 10871-10879.

23. Bo Zhang, Min Chen, Changbin Zhang*, Hong He, “Electrochemical oxidation of gaseous benzene on a Sb-SnO₂/foam Ti nano-coating electrode in all-solid cell”, Chemosphere217, (2019) 780-789.

22. Lian Wang, Guangyan Xu, Jinzhu Ma, Yunbo Yu, Qingxin Ma, Kuo Liu, Changbin Zhang*, Hong He, “Nanodispersed Mn₃O₄/g-Al₂O₃ for NO₂ elimination at room temperature”, Environ. Sci. Technol., 53, (2019) 10853-10862.

21. Bo Zhang, Min Chen, Lian Wang, Xu Zhao, Renzhi Hu, Hao Chen, Pinhua Xie, Changbin Zhang*, Hong He, “Electrochemical oxidation of volatile organic compounds in all-solid cell at ambient temperature”, Chem. Eng. J., 354, (2018) 93-104.

20. Hua Deng, Shunyu Kang, Jinzhu Ma^*,Changbin Zhang, Hong He, “Silver incorporated into cryptomelane-type manganese oxide boosts the catalytic oxidation of benzene”, Appl. Catal. B, 239, (2018) 214-222.

19. Hua Deng, Shunyu Kang, Chunying Wang,Hong He^*, Changbin Zhang^* “Palladium supported on low-surface-area fiber-based materials for catalytic oxidation of volatile organic compounds”, Chem. Eng. J., 348, (2018) 361-369.

18. Yafei Wang, Changbin Zhang^*,Hong He^*, “Insight into the role of Pd state on Pd-based catalysts in o-xylene oxidation at low temperature”, ChemCatChem, 10(5), (2018) 2670-2682.

17. Lian Wang, Yunbo Yu^*, Hong He^*, Yan Zhang, Xiubo Qin, Baoyi Wang, “Oxygen vacancy clusters essential for the catalytic activity of CeO₂ nanocubes for o-xylene oxidation”, Sci. Rep., 7, (2017) 12845.

16. 胡凌霄，王莲，王飞，张长斌*，贺泓*, “Pd/γ-Al₂O₃催化剂催化氧化邻-二甲苯”, 物理化学学报, 33(8), (2017) 1681-1688.

15. Lian Wang, Yafei Wang, Yan Zhang, Yunbo Yu*, Hong He*, Xiubo Qin, Baoyi Wang, “Shape dependence of nanoceria on complete catalytic oxidation of o-xylene”, Catal. Sci. Technol., 6, (2016) 4840-4848.

14. Lian Wang, Changbin Zhang*, Hong He, Fudong Liu, Caixia Wang, “Effect of doping metals on OMS-2/g-Al₂O₃ catalysts for plasma catalytic removal of o-xylene”, J. Phys. Chem. C, 120, (2016), 6136-6144.

13. Lian Wang, Hong He*, Changbin Zhang, Yafei Wang, Bo Zhang, “Effects of precursors for manganese-loaded g-Al₂O₃ catalysts on plasma-catalytic removal of o-xylene”, Chem. Eng. J., 288, (2016) 406-413.

12. Jie Zhang, Changbin Zhang*, Hong He*, “Remarkable promotion effect of trace sulfation on OMS-2 nanorod catalysts for the catalytic combustion of ethanol”, J. Environ. Sci., 35 (1), (2015) 69-75.

11. 张洁，张江浩，张长斌，贺泓*, “不同晶相结构二氧化锰催化完全氧化乙醇”，物理化学学报，31(2), (2015) 353-359.

10. Yafei Wang, Changbin Zhang, Yunbo Yu, Renliang Yue, Hong He*, “Ordered mesoporous and bulk Co₃O₄ supported Pd catalysts for catalytic oxidation of o-xylene”, Catal. Today, 242, (2015) 294-299.

9. Yafei Wang, Changbin Zhang, Fudong Liu, Hong He*, “Well-dispersed palladium supported on ordered mesoporous Co₃O₄ for catalytic oxidation of o-xylene”, Appl. Catal. B, 142-143 (2013) 72-79.

8. Shaoyong Huang, Changbin Zhang*, Hong He, “Effect of pretreatment on Pd/Al₂O₃ catalyst for catalytic oxidation of o-xylene at low temperature”, J. Environ. Sci., 2013, 25(6) 1206-1212.

7. Lian He, Yunbo Yu^*,Changbin Zhang, Hong He*, “Complete catalytic oxidation of o-xylene over CeO₂ nanocubes”, J. Environ. Sci., 23, (2011) 160-165.

6. Bo Zhang, Changbin Zhang*, Hong He*, Yunbo Yu, Lian Wang, Jie Zhang, “Electrochemical synthesis of catalytically active Ru/RuO₂ core-shell nanoparticles without stabilizer”, Chem. Mater., 22, (2010) 4056-4061.

5. Shaoyong Huang, Changbin Zhang, Hong He*, “In situ adsorption-catalysis system for the removal of o-xylene over an activated carbon supported Pd catalyst”, J. Environ. Sci., 21, (2009) 985-990.

4. Shaoyong Huang, Changbin Zhang, Hong He*, “Complete oxidation of o-xylene over Pd/Al₂O₃ catalyst at low temperature”, Catal. Today, 139, (2008)15-23.

3. 黄韶勇, 张长斌，贺泓*, “Pd/AC催化剂制备及其催化完全氧化邻-二甲苯性能”, 工业催化, 16, (2008) 38-45.

2. 王静, 吴银素*, 黄韶勇, 马子川, 贺泓, “γ-Al₂O₃负载的Pt, Pd催化剂上邻二甲苯的深度催化氧化”, 河北师范大学学报, 32, (2008) 73-77.

1. Lin Li, Changbin Zhang, Hong He, Junxin Liu*, “An integrated system of biological and catalytic oxidation for the removal of o-xylene from exhaust”, Catal.Today, 126, (2007) 338-344.

A series of C-doped TiO₂ catalysts with excellent performance for photocatalytic oxidation of ammonia were prepared, and the catalyst calcined at 400 ^oC had the best activity. The surface acidity is an important factor affecting the performance of a catalyst. The effects of exposed TiO₂ facets and surface F on the activity for photocatalytic oxidation of NH₃ were studied. It was found that TiO₂ with predominant {001} facets exposed had superior activity compared to TiO₂ with {101} or {010} facets exposed, and{001} facets of TiO₂ and surface F ions had a remarkable synergistic effect on PCO of NH₃. The DRIFTS results suggested that the separation efficiency of photogenerated electrons and holes is the crucial factor affecting the performance of NH₃ oxidation, and the main active species for NH₃ oxidation is the hole.  (Appl. Catal. B,2014, 152-153, 82; Appl. Catal. B,2017, 207, 3973; Appl. Catal. B, 2018, 223, 209)

2. Non-photocatalytic oxidation of indoor air ammonia

The Ag species state and Ag particle size have a significant influence on Ag/Al₂O₃ activity and N₂ selectivity in the SCO of NH₃ at low temperature. The SCO of NH₃ over Ag/Al₂O₃ follows different routes in different temperature regions. Ag⁰ is proposed to be an active species at low temperature (< 140 ^oC)，where NH₃ oxidation follows the –NH mechanism. However, at temperatures above 140 ^oC, Ag⁺ could also be an active species, and NH₃ oxidation follows an in situ selective catalytic reduction of NOx (iSCR) mechanism. (J. Catal., 2009, 268, 18; J. Catal., 2009, 261, 101)

Ag/nano-Al₂O₃ is an efficient catalyst for NH₃-SCO in the low temperature range. A remarkable nanosize effect for Al₂O₃ was observed in Ag/Al₂O₃ catalysts for the selective catalytic oxidation of ammonia. Small metallic Ag particles (Ag_NPs) in Ag/nano-Al₂O₃ facilitate the NH₃-SCO reaction following the new reaction pathway, which was named the N₂^– mechanism.

Dispersed Ag species on γ-Al₂O₃ are widely used for catalyzing a variety of reactions, including soot oxidation, ethylene epoxidation, NO_x reduction, and selective catalytic oxidation of ammonia (NH₃-SCO). The valence state, morphology and dispersion of Ag species can significantly affect the catalytic performance of Ag/γ-Al₂O₃. Herein, by using a number of surface-science measurements and density-functional theory (DFT) computation, we revealed that the terminal hydroxyl groups on the γ-Al₂O₃ surface are responsible for anchoring the Ag species. Hence, the presence of abundant terminal hydroxyl groups on nano-sized γ-Al₂O₃ surface can lead to remarkable single-silver-atom dispersion, thereby resulting in markedly higher performance than found with Ag clusters on micro-sized γ-Al₂O₃.  (ACS Catalysis, 2018, 8, 2670; ACS Catalysis, 2019, 9, 1437; Nat. Commun., 2020)

Relevant publications

12. Fei Wang, Jinzhu Ma, Shaohui Xin, Qiang Wang, Jun Xu, Changbin Zhang*, Hong He, Xiaocheng Zeng, “Resolving the puzzle of single-atom silver dispersion on nanosized γ-Al₂O₃ surface for high catalytic performance.” Nat. Commun. 11, (2020) 529-538.

11. Fei Wang, Guangzhi He, Bo Zhang, Min Chen, Xueyan Chen, Changbin Zhang*,Hong He, “Insights into the activation effect of H₂ pretreatment on Ag/Al₂O₃ catalyst for the selective catalytic oxidation of ammonia”, ACS Catal., 9, (2019) 1437-1445.

10. Fei Wang, Jinzhu Ma, Guangzhi He, Min Chen, Shaoxin Wang, Changbin Zhang^*,Hong He, “Synergistic Effect of TiO₂−SiO₂ in Ag/Si−Ti catalyst for the selective catalytic oxidation of ammonia”, Ind. Eng. Chem. Res., 57, (2018) 11903-11910.

9. Fei Wang, Jinzhu Ma, Guangzhi He, Min Chen, Changbin Zhang^*,Hong He^*, “Nanosize effect of Al₂O₃ in Ag/Al₂O₃ catalyst for the selective catalytic oxidation of ammonia”, ACS. Catal., 8, (2018) 2670-2682.

8. Min Chen, Jinzhu Ma, Bo Zhang, Fei Wang, Yaobin Li, Changbin Zhang*,Hong He, “Facet-dependent performance of anatase TiO₂ for photocatalytic oxidation of gaseous ammonia”, Appl. Catal. B, 223, (2018) 209-215.

7. Min Chen, Jinzhu Ma, Bo Zhang, Guangzhi He,Yaobin Li, Changbin Zhang*, Hong He, “Remarkable synergistic effect between {001} facets and surface F ions promoting hole migration on anatase TiO₂”, Appl. Catal. B, 207, (2017) 397-403.

6. Hongmin Wu, Jinzhu Ma, Yaobin Li, Changbin Zhang*, Hong He. “Photocatalytic oxidation of gaseous ammonia over fluorinated TiO₂ with exposed (001) facets”, Appl. Catal. B, 2014, 152-153, 82-87.

5. Hongmin Wu, Jinzhu Ma, Changbin Zhang*, Hong He, “Effect of calcination temperature on TiO₂ for the photocatalytic oxidation of gaseous NH₃”, J. Environ. Sci., 2014, 26(3) )1-10.

4. Li Zhang, Hong He*, “Mechanism of selective catalytic oxidation of ammonia to nitrogen over Ag/Al₂O₃”, J. Catal., 268, (2009) 18-25.

3. Li Zhang, Changbin Zhang, Hong He*, “The role of silver species in Ag/Al₂O₃ catalysts for the selective catalytic oxidation of ammonia to nitrogen”, J. Catal., 261, (2009) 101-109.

2. Shilong He, Changbin Zhang, Min Yang, Yu Zhang, Wenqing Xu, Nan Cao, Hong He*, “Selective catalytic oxidation of ammonia from MAP decomposition”, Sep. Purif. Technol., 58, (2007) 173-178.

1. Min Yang*, Chengqiang Wu, Changbin Zhang, Hong He, “Selective oxidation of ammonia over copper-silver based catalysts”, Catal. Today, 90, (2004) 263-267.

Relevant publications

9. Li Yang, Jinzhu Ma*, Xiaotong Li, Changbin Zhang, Hong He, “Enhancing oxygen vacancies of Ce-OMS-2 via optimized hydrothermal conditions to improve ozone decomposition”, Ind. Eng. Chem. Res., 59, (2020) 118-128.

8. Xiaotong Li, Jinzhu Ma*, Changbin Zhang, Runduo Zhang, Hong He, “Detrimental role of residual surface acid ions on ozone decomposition over Ce-modified γ-MnO₂ under humid conditions”, J. Environ. Sci., 91 (2020) 43-53.

7. Li Yang, Jinzhu Ma*, Xiaotong Li, Guangzhi He, Changbin Zhang, Hong He, “Tuning the fill percentage in the hydrothermal synthesis process to increase catalyst performance for ozone decomposition”, J. Environ. Sci., 87, (2020) 60-70.

6. Hua Deng, Shunyu Kang, Jinzhu Ma*, Lian Wang, Changbin Zhang, Hong He, “Role of structural defects in MnOx promoted by Ag doping in the catalytic combustion of volatile organic compounds and ambient decomposition of O₃”, Environ. Sci. Technol., 53, (2019) 10871-10879.

5. Xiaotong Li, Jinzhu Ma*, Changbin Zhang, Runduo Zhang, Hong He, “Facile synthesis of Ag modified manganese oxide for effective catalytic ozone decomposition”, J. Environ. Sci., 80, (2019), 159-168.

4. Xiaotong Li, Jinzhu Ma*, Li Yang, Guangzhi He, Changbin Zhang, Runduo Zhang, Hong He, “Oxygen vacancies induced by transition metal doping in g‑MnO₂ for highly efficient ozone decomposition”, Environ. Sci. Technol., 52, (2018) 12685-12696.

3. Jinzhu Ma, Caixia Wang,Hong He*, “Transition metal doped cryptomelane-type manganese oxide catalysts for ozone decomposition”, Appl. Catal. B, 201, (2017) 503-510.

2. Caixia Wang, Jinzhu Ma*, Fudong Liu, Hong He, Runduo Zhang, “The effects of Mn²⁺ precursors on the structure and ozone decomposition activity of cryptomelane-type manganese oxide (OMS-2) catalysts”, J. Phys. Chem. C, 119, (2015) 23119-23126.

1. Zhihua Lian, Jinzhu Ma, Hong He*, “Decomposition of high-level ozone under high humidity over Mn-Fe catalyst: The influence of iron precursors”, Catal. Commun., 59, (2015) 156-160.

Relevant publications

10. Lian Wang, Hong He*, Changbin Zhang, Li Sun, Sijin Liu, Shaoxin Wang, “Antimicrobial activity of silver loaded MnO₂ nanomaterials with different crystal phases against Escherichia coli”, J. Environ. Sci., 41, (2016) 112-120.

9. Lian Wang, Hong He*, Yunbo Yu, Li Sun, Sijin Liu, Changbin Zhang, Lian He, “Morphology-dependent bactericidal activities of Ag/CeO₂ catalysts against Escherichia coli”, J. Inorg. Biochem., 135, (2014) 45-53.

8. Lian Wang, Hong He*, Changbin Zhang, Li Sun, Sijin Liu, Renliang Yue, “Excellent antimicrobial properties of silver-loaded mesoporous silica SBA-15”, J. Appl. Microbiol., 116, (2014) 1106-1118.

7. Qingyun Chang, Hong He*, Zichuan Ma, “Efficient disinfection of Escherichia coli in water by silver loaded alumina”, J. Inorg. Biochem., 102, (2008) 1736-1742.

6. Qingyun Chang, Hong He*, Jincai Zhao, Min Yang, Jiuhui Qu, “Bactericidal activity of a Ce-promoted Ag/AlPO₄ catalyst using molecular oxygen in water”, Environ. Sci. Technol., 42, (2008) 1699-1704.

5. 常青云, 贺泓*, 曲久辉, 赵进才, “Ag-Ce/AlPO₄水中催化杀菌影响因素研究”, 催化学报, 29, (2008) 215-220.

4. Qingyun Chang, Lizhu Yan, Meixue Chen, Hong He*, Jiuhui Qu, “Bactericidal mechanism of Ag/Al₂O₃ against Escherichia coli”, Langmuir,23,(2007) 11197-11199.

3. Meixue Chen, Lizhu Yan, Hong He*, Qingyun Chang, Yunbo Yu, Jiuhui Qu, “Catalytic sterilization of Escherichia coli K 12 on Ag/Al₂O₃ surface”, J. Inorg. Biochem., 101, (2007) 817-823.

2. 闫丽珠, 陈梅雪, 贺泓*, 曲久辉, “氧化铝负载银催化剂的杀菌作用”, 催化学报,26(12), (2005) 1122-1126.

1. Hong He*, Xiaoping Dong, Min Yang, Qingxiang Yang, ShuminDuan, Yunbo Yu, Jun Han, Changbin Zhang, Lan Chen, Xin Yang, “Catalytic inactivation of SARS coronavirus, Escherichia coli and yeast on solid surface”, Catal. Commun., 5(3), (2004) 170-172.

The atmosphere is a mixed system of multi-pollutant and multi-media. Air pollution in China shows the characteristics of complex air pollution, in which the migration and transformation of pollutants will change. To reveal these new laws and mechanisms is not only a new challenge for atmospheric chemistry, but also a scientific basis for air pollution control in China. Haze frequently occurs with high concentrations of PM_2.5 due to the explosive growth of secondary particles. A key step in controlling pollution is revealing the formation mechanism of secondary particles under the conditions of complex air pollution in China.

At present, the prediction of PM_2.5 and its key secondary components in the atmospheric model shows large deviations from field measurements, which indicates that there are unknown mechanisms for the formation of secondary particles in the atmosphere. Based on laboratory simulation and field observation, we have revealed a new mechanism for the formation of secondary particles under the conditions of complex air pollution, and put forward the “haze chemistry” theory to explain the cause of complex air pollution in China. The main idea is that the oxidation capacity and the explosive growth of the transformation from gaseous pollutants to particulate pollutants increases under the conditions of complex air pollution. The decrease of environmental capacity has resulted in frequent haze pollution events in central and eastern China and made governance difficult. It is suggested that key pollutants such as SO₂, VOCs, NOx, black carbon and NH₃ should be controlled to improve the environmental capacity.

With the economic development of China, the emission of pollutants into the atmosphere, especially from the combustion of fossil fuels, leads to the deterioration of air quality and seriously threatens the health of the people. Air pollution in China has typical characteristics of complex pollution. Different stages and types of air pollution in developed countries are concentrated in China, resulting in increased air oxidizing capacity and frequent haze events. This is a new situation that developed countries have not experienced. There is no ready-made experience for reference in the prevention and control of air pollution in China. Therefore, there is an urgent need to carry out research on the causes and control of haze.

After more than two years of deliberation, the Chinese Academy of Sciences launched the Strategic Priority Research Program “Formation mechanism and control strategies of haze” in 2012. This project is led by the Research Center of Eco-Environmental Sciences (RCEES-CAS), with Professor He Hong as the chief scientist. There were 33 institutions participating in the program, bringing together outstanding domestic teams in the fields of atmospheric physics, atmospheric chemistry, environmental optics, air pollution control and environmental policy. Five projects were set up, and the research work included laboratory simulation of haze formation mechanisms, field observation and source apportionment, numerical simulation and collaborative control schemes, development of haze monitoring equipment and key technology, and leading-edge technology for key pollutant control. This program has strongly promoted important follow-on research programs, including the joint major research plan of NSFC ” Formation mechanism, Health Effects and Coping Strategy of Complex Air Pollution in China” (2015), the National Key R&D Program of MOST “Air Pollution Prevention and Control” (2016), and the National Research Program for Key Issues in Air Pollution Control (2017).

Through a series of reform measures, such as refining and looking forward to scientific and technological objectives, dynamically adjusting research layout and optimizing resource allocation, focusing on the major strategic needs of the country and closely combining with the international scientific frontier, this program has brought together a group of excellent scientific researchers, and significantly improved collaborative innovation. An excellent atmospheric haze research team with a full range of disciplines and reasonable structure has been gathering, and a group of academic leaders and outstanding young scientific and technological talents are being cultivated. These members of the research team played a key role in the subsequent establishment and implementation of major air pollution prevention and control projects in China.

This program has developed a number of key technologies with independent intellectual property, achieved original research breakthroughs with important international influence, and put forward the conceptual model and theoretical framework of the third type of haze, chemical smog, which is different from London smog and Los Angeles photochemical smog. These achievements play a leading role in the development of the atmospheric environment discipline, and provide scientific and feasible haze control technologies and solutions. The overall research level is at an advanced rank internationally. The construction of atmospheric environment for monitoring, source inventory and prediction and warning technology systems provides an important foundation platform for future atmospheric science research in China. Remarkable achievements have been made in the promotion and application of pollution control technology, which are promoting the development of haze prevention and control work in China. 11 of the special consultation reports submitted to the CPC Central Committee and the State Council were adopted.

1. Metal oxide catalysts for NH₃-SCR reaction

1.1. Design of low V-loaded NH₃-SCR catalyst with high NH₃-SCR performance and study of its structure-activity relationship

By controlling the sulfur content of the TiO₂ support, the catalytically active center, oligomeric vanadia, was successfully designed and synthesized. The low-temperature SCR activity was significantly improved under low vanadium loading (1 wt.%). The whole NH₃-SCR process of V-based catalysts was clarified at the atomic level with DFT calculations. The coupling effect of oligomeric vanadia not only shortens the reaction pathway for the regeneration of redox sites but also substantially reduces the overall reaction barrier of the catalytic cycle. Theoretical and experimental evidence indicates that the oligomeric vanadyl species, rather than monomeric vanadyl species, determine the NH₃-SCR activity of vanadia-based catalysts, especially under low-temperature conditions. These results provide a theoretical basis for the development of high-efficiency NH₃-SCR catalysts, successfully guiding the improvement of the traditional V-based catalyst and realizing the industrial application of high-efficiency V-based catalysts (Sci. Adv., 2018, 4, eaau4637; Chin. J. Catal., 2014, 35, 1438; Catal. Sci. Technol., 2020, 10, 311).

1.2. Novel cerium-based oxide catalysts

Based on the in-depth understanding of the structure-activity relationship of NH₃-SCR catalysts and the reaction mechanism at different temperature ranges, we established a principle for the design of NH₃-SCR catalysts that involves close coupling of the redox and acid sites, which guided the development of metal oxide catalysts with excellent performance.

Through the combination of cerium and titanium oxides as redox and acidic components, respectively, a Ce-based NH₃-SCR catalyst was developed for the first time; through improvement of the preparation method, the coupling of cerium and titanium oxides was enhanced, and the activity of the catalyst was promoted; through the introduction of a promoter, the redox and acidic functions were enhanced simultaneously, and the temperature window was widened; through the complete substitution of Ti with W, the obtained Ce-W oxide catalyst with closely coupled Ce and W exhibited superior performance, enabling the NO_x emissions from a heavy duty diesel engine to meet the Euro V limit (Chinese V limit) in an engine bench test; through the introduction of a third component, recently we further improved the hydrothermal stability of the catalyst. (Catal. Commun., 2008, 9, 1453; Chem. Commun., 2011, 47, 8046; ChemCatChem., 2011, 3, 1286; Appl. Catal. B, 2012,115-116, 100; Chem. Commun. 2014, 50, 8445; Chin. J. Catal., 2014, 35, 1251; Catal. Commun., 2015, 59, 226; Catal. Sci. Technol., 2015, 5, 2290; Environ. Sci. Technol., 2018, 52, 11769; J. Catal., 2019, 369, 372)

1.3. Novel iron-based oxide catalysts

Under the guidance of design principles, a novel iron titanate catalyst was developed, by the combination of Fe oxides with strong redox functions and TiO₂ with excellent acid properties. On this catalyst, the Fe³⁺ and Ti⁴⁺ are connected with double oxygen bridges to form a short-range ordered structure, with redox centers and acid centers closely coupled at the atomic level, providing excellent NH₃-SCR activity and H₂O/SO₂ durability. Recently, through the combination of Fe oxides and WO₃, an Fe-W oxide catalyst with excellent NH₃-SCR performance was developed as well. (Chem. Commun., 2008, 2043; Appl. Catal. B: Environ., 2010, 96, 408; J. Phys. Chem. C, 2010, 114, 16929; App. Catal. B: Environ., 2011,103, 369; App. Catal. B: Environ., 2018, 230, 165) 

The redox-acid site coupling principle has successfully guided the development of highly efficient oxide catalysts, using the variable-valence metals Fe, Ce, and Mn as redox components, and Ti and W as acid components. These achievements provide a strong theoretical basis for the development and application of novel high-efficiency NH₃-SCR catalysts. At the same time, it theoretically guided the improvement of the traditional V-based catalyst and the industrial production of the improved V-based catalyst. The above-mentioned achievements won the second prize of the State Natural Science Award in 2019.

2. Ion-exchanged zeolite catalyst for NH₃-SCR reaction

2.1. Cu-based small-pore zeolites with high NH₃-SCR activity and hydrothermal stability

The DOC+DPF+SCR+AOC aftertreatment technique, which meets the upcoming Diesel Emission Standard China VI, was recently developed. The Cu-based Chabazite (CHA) small-pore zeolites Cu-SSZ-13 and Cu-SAPO-34 with high NH₃-SCR catalytic activity and hydrothermal stability were synthesized via a one-pot method for this application. (Environ. Sci. Technol., 2014, 48, 566; Chem. Eng. J., 2016, 294, 254)

2.2. NH₃-SCR reaction pathway over Cu-SSZ-13

An abnormal fast SCR reaction was found over small-pore Cu-SSZ-13 zeolite: under SCR reaction conditions, the presence of NO₂ inhibits NO_x reduction instead of promoting it. This is because the kinetic diameter of NO₂ is larger than the small pores (3.8 Å) of Cu-SSZ-13, resulting in the formation of NH₄NO₃ with NH₄⁺ on the Bronsted acid sites. The accumulated NH₄NO₃ would block the zeolite pores and further inhibit the NO reduction at Cu active sites. When the reaction temperature is above the decomposition temperature of NH₄NO₃, the NO reduction is recovered. By comparing the standard and fast SCR over the H-SSZ-13 support, it was found that NO can only be reduced at Cu active sites under standard SCR conditions. Under fast SCR conditions, however, NO can be also reduced at acid sites through the fast SCR reaction. (Catal. Sci. Technol., 2014, 4, 1104; J. Phys. Chem. C, 2018, 122, 25948)

2.3. Deactivation mechanism during hydrothermal aging of Cu-SSZ-13

Compared to fresh Cu-SSZ-13 (FR-Cu-SSZ-13), Cu-SSZ-13 hydrothermally aged at 750 ℃ (HA-Cu-SSZ-13) showed marked deactivation of NOx efficiency and a narrower operating temperature window. The activity of Cu-SSZ-13 hydrothermally aged at 750 ℃ decreased progressively in the presence of SO₂ (SA-Cu-SSZ-13), only achieving a maximum NO_x conversion of 85%. The characterization results of H₂-TPR, EPR, DRIFTS, XRD, and NMR techniques showed that the accumulation of CuO_x clusters from active Cu²⁺ and zeolite framework dealumination are the main reasons for hydrothermal aging deactivation. The presence of SO₂ increased the acidity of the aging atmosphere, therefore accelerating the destruction of the zeolite structure and transformation of Cu²⁺ to CuO_x clusters. (Catal. Today, 2019, 320, 84; Appl. Catal. B: Environ., 2020, 266, 118655)

Cu-SAPO-34 has a higher hydrothermal stability at high temperatures compared to Cu-SSZ-13. At low temperatures below 100℃, however, the Si-O-Al in Cu-SAPO-34 is easily broken down in damp environments, resulting in Cu accumulation, which further leads to catalyst deactivation. The low-temperature hydrothermal stability can be improved by introducing a small amount of Ce in the in-situ synthesized Cu-SAPO-34.

2.4. New-type Cu-based small-pore zeolites applied to NH₃-SCR reaction

Cu-SSZ-39 (AEI-type) has an extremely similar structure to that of Cu-SSZ-13 (CHA-type). The difference between the AEI and CHA structures is the connection mode of the double 6-rings (D6R). The neighboring D6Rs have mirror symmetry in AEI while being arranged in parallel in CHA. This leads to AEI zeolite having a more tortuous channel structure than CHA zeolite, which inhibits dealumination during hydrothermal aging and makes the zeolite framework structure more stable. On the other hand, Cu-SSZ-39 zeolite contains more paired framework Al, leading to Cu-SSZ-39 catalysts having more hydrothermally stable Cu²⁺-2Z species as compared to Cu-SSZ-13, and this makes Cu-SSZ-39 accumulate less CuOx during hydrothermal aging. Therefore, Cu-SSZ-39 has higher hydrothermal stability than Cu-SSZ-13. (Appl. Catal. B: Environ., 2020, 264, 118511)

Cu-SSZ-50 with RTH-type structure contains two types of 8MR pores and two active sites, which are highly active Cu²⁺ species (α species) next to 8MR and relatively inactive Cu²⁺ species (β species) next to rth cages. The Cu-SSZ-50 zeolite with active α species showed excellent NH₃-SCR performance, while Cu-SSZ-50 with β species only showed poor NH₃-SCR performance. After hydrothermal aging, active Cu²⁺ species easily transform to inert sites, resulting in low deNO_x activity. High Cu loading in the Cu-SSZ-50 catalyst limits the Cu mobility during hydrothermal aging and preserves more active Cu²⁺ species, resulting in good NH₃-SCR performance. (Catal. Sci. Technol., 2019, 9, 106)

Relevant publications

59) Yulong Shan, Jinpeng Du, Yunbo Yu, Wenpo Shan, Xiaoyan Shi*, Hong He*, Precise control of post-treatment significantly increases hydrothermal stability of in-situ synthesized Cu-zeolites for NH₃-SCR reaction, Appl. Catal. B, 266, (2020) 118655.

58) Yulong Shan, Wenpo Shan, Xiaoyan Shi, Jinpeng Du, Yunbo Yu*, Hong He*, A comparative study of the activity and hydrothermal stability of Al-rich Cu-SSZ-39 and Cu-SSZ-13, Appl. Catal. B, 264, (2020) 118511.

57) Na Zhu, Wenpo Shan*, Zhihua Lian, Yan Zhang, Kuo Liu, Hong He, A superior Fe-V-Ti catalyst with high activity and SO₂ resistance for the selective catalytic reduction of NO_x with NH₃. J. Hazard. Mater., 382, (2020) 120970.

56) Zhihua Lian, Shaohui Xin, Na Zhu, Qiang Wang, Jun Xu, Yan Zhang, Wenpo Shan*, Hong He, Effect of treatment atmosphere on the vanadium species of V/TiO₂ catalysts for the selective catalytic reduction of NO_x with NH₃. Catal. Sci. Technol, 10, (2020) 311-314.

55) Yulong Shan, Xiaoyan Shi, Jinpeng Du, Zidi Yan, Yunbo Yu, Hong He*, SSZ-13 synthesized by solvent-free method: A potential candidate for NH₃-SCR catalyst with high activity and hydrothermal stability, Ind. Eng. Chem. Res., 58, (2019) 5397-5403.  

54) Yulong Shan, Xiaoyan Shi, Zidi Yan, Jingjing Liu, Yunbo Yu, Hong He*, Deactivation of Cu-SSZ-13 in the presence of SO₂ during hydrothermal aging, Catal. Today, 320, (2019) 84-90.  

53) Guangyan Xu, Jinzhu Ma, Lian Wang, Zhihui Lv, Shaoxin Wang, Yunbo Yu*, Hong He*, The mechanism of the H₂ effect on NH₃-SCR over Ag/Al₂O₃: Kinetic and DRIFTS studies, ACS Catal., 9, (2019) 10489-10498.

52) Yulong Shan, Xiaoyan Shi, Jinpeng Du, Yunbo Yu, Hong He*, Cu-exchanged RTH-type zeolites for NH₃-selective catalytic reduction of NO_x: Cu distribution and hydrothermal stability, Catal. Sci. Technol., 9, (2019) 106-115.

51) Guangzhi He, Bo Zhang, Hong He*, Xueyan Chen, Yulong Shan, Atomic-scale insights into zeolite-based catalysis in N₂O decomposition, Sci. Total Environ., 673, (2019) 266-271.

50) Kuo Liu, Zidi Yan, Hong He, Qingcai Feng, Wenpo Shan*, The effect of H₂O on a vanadium-based catalyst for NH₃-SCR at low temperatures: a quantitative study of the reaction pathway and active sites, Catal. Sci. Technol., 9, (2019) 5593-5604.

49) Kuo Liu, Hong He*, Yunbo Yu, Zidi Yan, Weiwei Yang, Wenpo Shan, Quantitative study of the NH₃-SCR pathway and the active site distribution over CeWO_x at low temperatures, J. Catal., 369, (2019) 372-384.

48) Wen Xie, Yunbo Yu*, Hong He*, Shape dependence of support for the NO_x storage and reduction catalyst, J. Environ. Sci. 75, (2019) 396-407.

47) Na Zhu, Zhihua Lian, Yan Zhang, Wenpo Shan*, Hong He, The promotional effect of H₂ reduction treatment on the low-temperature NH₃-SCR activity of Cu/SAPO-18, Appl. Surf. Sci., 483 (2019) 536-544.

46) Na Zhu, Zhihua Lian, Yan Zhang, Wenpo Shan*, Hong He, Improvement of low-temperature catalytic activity over hierarchical Fe-Beta catalysts for selective catalytic reduction of NO_x with NH₃, Chin. Chem. Lett., 30 (2019) 867-870.

45) Zhihua Lian, Wenpo Shan, Meng Wang, Hong He*, Qingcai Feng*, The balance of acidity and redox capability over modified CeO₂ catalyst for the selective catalytic reduction of NO with NH₃, J. Environ. Sci. 79, (2019) 273-279.

44) Guangzhi He, Zhihua Lian, Yunbo Yu, Yang Yang, Kuo Liu, Xiaoyan Shi, Zidi Yan, Wenpo Shan, Hong He*, Polymeric vanadyl species determine the low-temperature activity of V-based catalysts for the SCR of NO_x with NH₃, Sci. Adv., 4, (2018) eaau4637.  

43) Zidi Yan, Xiaoyan Shi*, Yunbo Yu, Hong He, Alkali resistance promotion of Ce doped vanadium-titanic based NH₃-SCR catalysts, J. Environ. Sci., 73, (2018) 155-161.

42) Jingjing Liu, Xiaoyan Shi, Yulong Shan, Zidi Yan, Wenpo Shan, Yunbo Yu, Hong He^*, Hydrothermal stability of CeO₂-WO₃-ZrO₂ mixed oxides for selective catalytic reduction of NO_x by NH₃, Environ. Sci. Technol., 52, (2018) 11769-11777.  

41) Yulong Shan, Xiaoyan Shi, Guangzhi He, Kuo Liu, Zidi Yan, Yunbo Yu, Hong He*, Effect of NO₂ addition on the NH₃-SCR over small-pore Cu-SSZ-13 zeolites with varying Cu loadings, J. Phys. Chem. C, 122, (2018) 25948-25953.

40) Wenpo Shan, Yang Geng, Yan Zhang, Zhihua Lian, Hong He*, A CeO₂/ZrO₂-TiO₂ catalyst for the selective catalytic reduction of NO_x with NH₃, Catalysts, 8, (2018) 592-603.

39) Zhihua Lian, Wenpo Shan, Yan Zhang, Meng Wang, Hong He*, Morphology-dependent catalytic performance of NbO_x/CeO₂ catalysts for selective catalytic reduction of NO_x with NH₃, Ind. Eng. Chem. Res., 57, (2018) 12736-12741.

38) Fudong Liu, Wenpo Shan, Zhihua Lian, Jingjing Liu, Hong He*, The smart surface modification of Fe₂O₃ by WO_x for significantly promoting the selective catalytic reduction of NO_x with NH₃, Appl. Catal. B, 230, (2018) 165-176.

37) Can Niu, Xiaoyan Shi, Fudong Liu, Kuo Liu, Lijuan Xie, Yan You*, Hong He*, High hydrothermal stability of Cu-SAPO-34 catalysts for the NH₃-SCR of NO_x, Chem. Eng. J., 294, (2016) 254-263.

36) Can Niu, Xiaoyan Shi*, Kuo Liu, Yan You, Shaoxin Wang, Hong He, A novel one-pot synthesized CuCe-SAPO-34 catalyst with high NH₃-SCR activity and H₂O resistance. Catal. Commun., 81, (2016) 20–23.

35) Weiwei Yang, Fudong Liu*, Lijuan Xie, Zhihua Lian, Hong He*, The Effect of V₂O₅ Additive on the SO₂ Resistance of Fe₂O₃/AC Catalyst for NH₃-SCR of NO_x at Low Temperatures, Ind. Eng. Chem. Res., 55, (2016) 2677-2685.

34) Shipeng Ding, Fudong Liu*, Xiaoyan Shi, Hong He*, Promotional effect of Nb additive on the activity and hydrothermal stability for the selective catalytic reduction of NO_x with NH₃ over CeZrO_x catalyst, Appl. Catal. B, 180, (2016) 766-774.

33) Xiaoyan Shi*, Hong He, Lijuan Xie, The effect of Fe species distribution and acidity of Fe-ZSM-5 on the hydrothermal stability and SO₂ and hydrocarbons durability in NH₃-SCR reaction, Chin. J. Catal., 36, (2015) 649-656.

32) Shipeng Ding, Fudong Liu*, Xiaoyan Shi, Kuo Liu, Zhihua Lian, Lijuan Xie, Hong He*, Significant promotion effect of Mo additive on novel Ce-Zr mixed oxide catalyst for the selective catalytic reduction of NO_x with NH₃, ACS Appl. Mater. Interfaces., 7, (2015) 9497-9506.

31) Lijuan Xie, Fudong Liu, Xiaoyan Shi, Feng-Shou Xiao, Hong He*, Effects of post-treatment method and Na co-cation on thehydrothermal stability of Cu–SSZ-13 catalyst for the selective catalytic reduction of NOx with NH₃, Appl.Catal. B., 179, (2015) 206-212.

30) Kuo Liu, Fudong Liu, Lijuan Xie, Wenpo Shan, Hong He*, DRIFTS study of a Ce-W mixed oxide catalyst for the selective catalytic reduction of NO_x with NH₃, Catal. Sci. Technol., 5, (2015) 2290-2299.

29) Zhihua Lian, Fudong Liu*, Hong He*, Kuo Liu, “Nb-doped VO_x/CeO₂ catalyst for NH₃-SCR of NO_x at low temperatures, RSC Adv., 5, (2015) 37675-37681.

28) Wenpo Shan, Fudong Liu*, Yunbo Yu, Hong He*, Chenglin Deng, Xinyun Zi, High-efficiency reduction of NO_x emission from diesel exhaust using a CeWO_x catalyst, Catal. Commun., 59, (2015) 226-228. 

27) Zhihua Lian, Fudong Liu, Hong He*, Effect of preparation methods on the activity of VOx/CeO₂ catalysts for the selective catalytic reduction of NO_x with NH₃, Catal. Sci. Technol., 5(1), (2015) 389-396. 

26) Zhihua Lian, Jinzhu Ma, Hong He*, Decomposition of high-level ozone under high humidity over Mn–Fe catalyst: The influence of iron precursors, Catal. Commun., 59, (2015) 156-160.

25) Zhihua Lian, Fudong Liu, Hong He*, Enhanced activity of Ti-modified V₂O₅/CeO₂ catalyst for the selective catalytic reduction of NO_x with NH₃, Ind. Eng. Chem. Res., 53, (2014) 19506-19511.

24) Wenpo Shan, Fudong Liu, Yunbo Yu, Hong He*, The use of ceria for the selective catalytic reduction of NO_x with NH₃, Chin. J. Catal., 35, (2014) 1251-1259.

23) Fudong Liu, Wenpo Shan, Dawei Pan, Tengying Li, Hong He*, Selective catalytic reduction of NO_x by NH₃ for heavy-duty diesel vehicles, Chin. J. Catal., 35, (2014) 1438-1445.

22) Fudong Liu, Yunbo Yu, Hong He*, Environmentally-benign catalysts for the selective catalytic reduction of NO_x from diesel engines: Structure-activity relationship and reaction mechanism aspects, Chem. Commun., 50 (62), (2014) 8445-8463.

21) Zhihua Lian, Fudong Liu, Hong He*, Xiaoyan Shi, Jiansong Mo, Zhongbiao Wu, Manganese–niobium mixed oxide catalyst for the selective catalytic reduction of NO_x with NH₃ at low temperatures, Chem. Eng. J., 250, (2014) 390-398.

20) Lijuan Xie, Fudong Liu, Kuo Liu, Xiaoyan Shi, Hong He*, Inhibitory effect of NO₂ on the selective catalytic reduction of NO_x with NH₃ over one-pot synthesized Cu-SSZ-13 catalyst, Catal. Sci. Technol., 4, (2014) 1104-1110.

19) Lijuan Xie, Fudong Liu, Limin Ren, Xiaoyan Shi, Fengshou Xiao, Hong He*, Excellent performance of one-pot synthesized Cu-SSZ-13 catalyst for the selective catalytic reduction of NO_x with NH₃, Environ. Sci. Technol., 48, (2014) 566-572.

18) Fudong Liu, Hong He*, Lijuan Xie, XAFS study on the specific deoxidation behavior of iron titanate catalyst for the selective catalytic reduction of NO_x with NH₃, ChemCatChem., 5, (2013) 3760-3769.

17) Xiaoyan Shi, Fudong Liu, Lijuan Xie, Wenpo Shan, Hong He*, NH₃‑SCR performance of fresh and hydrothermally aged Fe-ZSM‑5 in standard and fast selective catalytic reduction reactions, Environ. Sci. Technol., 47, (2013) 3293-3298.

16) Fudong Liu, Wenpo Shan, Zhihua Lian, Lijuan Xie, Weiwei Yang, Hong He*, Novel MnWO_x catalyst with remarkable performance for low temperature NH₃-SCR of NO_x, Catal. Sci. Technol., 3, (2013) 2699-2707.

15) Fudong Liu, Hong He*, Zhihua Lian, Wenpo Shan, Lijuan Xie, Kiyotaka Asakura, Weiwei Yang, Hua Deng, Highly dispersed iron vanadate catalyst supported on TiO₂ for the selective catalytic reduction of NO_x with NH₃, J. Catal., 307, (2013) 340-351.

14) Fudong Liu, Kiyotaka Asakurab*, Pengyang Xie, Jianguo Wang，Hong He*, An XAFS study on the specific microstructure of active species in iron titanate catalyst for NH₃-SCR of NO_x, Catal. Today, 201, (2013) 131-138.

13) Wenpo Shan, Fudong Liu*, Hong He*, Xiaoyan Shi, Changbin Zhang, An environmentally-benign CeO₂-TiO₂ catalyst for the selective catalytic reduction of NO_x with NH₃ in simulated diesel exhaust, Catal. Today, 184, (2012) 160-165.

12) Wenpo Shan, Fudong Liu*, Hong He*, Xiaoyan Shi, Changbin Zhang, A superior Ce-W-Ti mixed oxide catalyst for the selective catalytic reduction of NO_x with NH₃, Appl. Catal. B, 115-116, (2012) 100-106.

11) Fudong Liu, Hong He*, Changbin Zhang, Wenpo Shan, Xiaoyan Shi, Mechanism of the selective catalytic reduction of NO_x with NH₃ over environmental-friendly iron titanate catalyst, Catal. Today, 175(1), (2011) 18-25.

10) Wenpo Shan, Fudong Liu*, Hong He*, Xiaoyan Shi, Changbin Zhang, The Remarkable Improvement of a Ce-Ti based Catalyst for NOx Abatement, Prepared by a Homogeneous Precipitation Method, ChemCatChem., 3, (2011) 1286-1289.

9) Wenpo Shan, Fudong Liu*, Hong He, Xiaoyan Shi, Changbin Zhang, Novel cerium-tungsten mixed oxide catalyst for the selective catalytic reduction of NO_x with NH₃, Chem. Commun., 47, (2011) 8046-8048.

8) Fudong Liu, Kiyotaka Asakura, Hong He*, Yongchun Liu，Wenpo Shan, Xiaoyan Shi, Changbin Zhang, Influence of calcination temperature on iron titanate catalyst for the selective catalytic reduction of NO_x with NH₃, Catal. Today, 164, (2011) 520-527.

7) Fudong Liu, Kiyotaka Asakura, Hong He*, Wenpo Shan, Xiaoyan Shi, Changbin Zhang, Influence of sulfation on iron titanate catalyst for the selective catalytic reduction of NO_x with NH₃, Appl. Catal. B, 103, (2011) 369-377.

6) Fudong Liu, Hong He*, Structure-activity relationship of iron titanate catalysts in the selective catalytic reduction of NO_x with NH₃, J. Phys. Chem. C, 114, (2010) 16929-16936.   

5) Fudong Liu, Hong He*, Selective catalytic reduction of NO with NH₃ over manganese substituted iron titanate catalyst: Reaction mechanism and H₂O/SO₂ inhibition mechanism study, Catal. Today, 153，(2010) 70-76.

4) Fudong Liu, Hong He*, Changbin Zhang, Zhaochi Feng, Lirong Zheng, Yaning Xie, Tiandou Hu, Selective catalytic reduction of NO with NH₃ over iron titanate catalyst: Catalytic performance and characterization, Appl. Catal. B, 96, (2010) 408-420.

3) Fudong Liu, Hong He*, Yun Ding, Changbin Zhang, Effect of manganese substitution on the structure and activity of iron titanate catalyst for the selective catalytic reduction of NO with NH₃, Appl. Catal. B, 93, (2009) 194-204.  

2) Wenqing Xu, Hong He*, Yunbo Yu, Deactivation of a Ce/TiO₂ catalyst by SO₂ in the selective catalytic reduction of NO by NH₃, J. Phys. Chem. C, 113, (2009) 4426-4432.

1) Wenqing Xu, Yunbo Yu, Changbin Zhang, Hong He*, Selective catalytic reduction of NO by NH₃ over a Ce/TiO₂ catalyst, Catal. Commun., 9, (2008) 1453-1457.