1
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Ma Q, Chu B, He H. Revealing the Contribution of Interfacial Processes to Atmospheric Oxidizing Capacity in Haze Chemistry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6071-6076. [PMID: 38551192 DOI: 10.1021/acs.est.3c08698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
The atmospheric oxidizing capacity is the most important driving force for the chemical transformation of pollutants in the atmosphere. Traditionally, the atmospheric oxidizing capacity mainly depends on the concentration of O3 and other gaseous oxidants. However, the atmospheric oxidizing capacity based on gas-phase oxidation cannot accurately describe the explosive growth of secondary particulate matter under complex air pollution. From the chemical perspective, the atmospheric oxidizing capacity mainly comes from the activation of O2, which can be achieved in both gas-phase and interfacial processes. In the heterogeneous or multiphase formation pathways of secondary particulate matter, the enhancement of oxidizing capacity ascribed to the O2/H2O-involved interfacial oxidation and hydrolysis processes is an unrecognized source of atmospheric oxidizing capacity. Revealing the enhanced oxidizing capacity due to interfacial processes in high-concentration particulate matter environments and its contribution to the formation of secondary pollution are critical in understanding haze chemistry. The accurate evaluation of atmospheric oxidizing capacity ascribed to interfacial processes is also an important scientific basis for the implementation of PM2.5 and O3 collaborative control in China and around the world.
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Affiliation(s)
- Qingxin Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Biwu Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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2
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Guan J, Li D, Feng J, Xu P, Li Z, Ge S, Chen H, Zhang K. Enhanced photocatalytic ammonia oxidation activity and nitrogen selectivity over Ag/AgCl/N-TiO 2 photocatalyst. J Environ Sci (China) 2024; 138:395-405. [PMID: 38135405 DOI: 10.1016/j.jes.2023.03.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 03/14/2023] [Accepted: 03/15/2023] [Indexed: 12/24/2023]
Abstract
The removal of ammonia (NH3) emitted from agricultural and industrial activities is of great significance to protect human health and ecological environment. Photocatalytic NH3 oxidation to N2 under mild conditions is a promising strategy. However, developing visible light photocatalysts for NH3 oxidation is still in its infancy. Here, we fabricate N-TiO2 and Ag/AgCl/N-TiO2 photocatalysts by sol-gel and photodeposition methods, respectively. The introduction of N not only endows TiO2 with visible light response (absorption edge at 460 nm) but also results in the formation of heterophase junction (anatase and rutile). Thus, N-TiO2 shows 2.0 and 1.8 times higher than those over anatase TiO2 and commercial TiO2 for NH3 oxidation under full spectrum irradiation. Meanwhile, surface modification of Ag can simultaneously enhance visible light absorption (generating localized surface plasmon resonance effect) and charge separation efficiency. Therefore, the photocatalytic activity of Ag/AgCl/N-TiO2 is further improved. Furthermore, the presence of N and Ag also enhances the selectivity of N2 product owing to the change of reaction pathway. This work simultaneously regulates photocatalytic conversion efficiency and product selectivity, providing some guidance for developing highly efficient photocatalysts for NH3 elimination.
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Affiliation(s)
- Jiaojiao Guan
- College of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Daorong Li
- College of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Jiahui Feng
- College of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Peng Xu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology, Beijing 100190, China
| | - Zhaonian Li
- College of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Siqi Ge
- College of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Hongxia Chen
- College of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China.
| | - Kunfeng Zhang
- College of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China; Department of Chemistry, Tsinghua University, Beijing 100084, China.
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3
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Chen R, Li J, Wang J, Yang W, Shen S, Dong F. Continuous NO Upcycling into Ammonia Promoted by SO 2 in Flue Gas: Poison Can Be a Gift. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:12127-12134. [PMID: 37531586 DOI: 10.1021/acs.est.3c04192] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/04/2023]
Abstract
Although ammonia (NH3) synthesis efficiency from the NO reduction reaction (NORR) is significantly promoted in recent years, one should note that NO is one of the major air pollutants in the flue gas. The limited NO conversion ratio is still the key challenge for the sustainable development of the NORR route, which potentially contributes more to contaminant emissions rather than its upcycling. Herein, we provide a simple but effective approach for continuous NO reduction into NH3, promoted by coexisting SO2 poison as a gift in the flue gas. It is significant to discover that SO2 plays a decisive role in elevating the capacity of NO absorption and reduction. A unique redox pair of SO2-NO is constructed, which contributes to the exceptionally high conversion ratio for both NO (97.59 ± 1.42%) and SO2 (99.24 ± 0.49%) in a continuous flow. The ultrahigh selectivity for both NO-to-NH3 upcycling (97.14 ± 0.55%) and SO2-to-SO42- purification (92.44 ± 0.71%) is achieved synchronously, demonstrating strong practicability for the value-added conversion of air contaminants. The molecular mechanism is revealed by comprehensive in situ technologies to identify the essential contribution of SO2 to NO upcycling. Besides, realistic practicality is realized by the efficient product recovery and resistance ability against various poisoning effects. The proposed strategy in this work not only achieves a milestone efficiency for NH3 synthesis from the NORR but also raises great concerns about contaminant resourcing in realistic conditions.
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Affiliation(s)
- Ruimin Chen
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, People's Republic of China
| | - Jieyuan Li
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, People's Republic of China
| | - Jielin Wang
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, People's Republic of China
| | - Weiping Yang
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, People's Republic of China
| | - Shujie Shen
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, People's Republic of China
| | - Fan Dong
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, People's Republic of China
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4
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Cao Q, Chu B, Zhang P, Ma Q, Ma J, Liu Y, Liu J, Zhao Y, Zhang H, Wang Y, He H. Effects of SO 2 on NH 4NO 3 Photolysis: The Role of Reducibility and Acidic Products. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37235870 DOI: 10.1021/acs.est.3c01082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Nitrate photolysis is a vital process in secondary NOx release into the atmosphere. The heterogeneous oxidation of SO2 due to nitrate photolysis has been widely reported, while the influence of SO2 on nitrate photolysis has rarely been investigated. In this study, the photolysis of nitrate on different substrates was investigated in the absence and presence of SO2. In the photolysis of NH4NO3 on the membrane without mineral oxides, NO, NO2, HONO, and NH3 decreased by 17.1, 6.0, 12.6, and 57.1% due to the presence of SO2, respectively. In the photolysis of NH4NO3 on the surface of mineral oxides, SO2 also exhibited an inhibitory effect on the production of NOx, HONO, and NH3 due to its reducibility and acidic products, while the increase in surface acidity due to the accumulation of abundant sulfate on TiO2 and MgO promoted the release of HONO. On the photoactive oxide TiO2, HSO3-, generated by the uptake of SO2, could compete for holes with nitrate to block nitrate photolysis. This study highlights the interaction between the heterogeneous oxidation of SO2 and nitrate photolysis and provides a new perspective on how SO2 affects the photolysis of nitrate absorbed on the photoactive oxides.
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Affiliation(s)
- Qing Cao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Biwu Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Peng Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Qingxin Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Jinzhu Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Yuan Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yaqi Zhao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Yonghong Wang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
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5
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Liu J, Li B, Deng H, Yang Y, Song W, Wang X, Luo Y, Francisco JS, Li L, Gligorovski S. Resolving the Formation Mechanism of HONO via Ammonia-Promoted Photosensitized Conversion of Monomeric NO 2 on Urban Glass Surfaces. J Am Chem Soc 2023; 145:11488-11493. [PMID: 37196053 DOI: 10.1021/jacs.3c02067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Understanding the formation processes of nitrous acid (HONO) is crucial due to its role as a primary source of hydroxyl radicals (OH) in the urban atmosphere and its involvement in haze events. In this study, we propose a new pathway for HONO formation via the UVA-light-promoted photosensitized conversion of nitrogen dioxide (NO2) in the presence of ammonia (NH3) and polycyclic aromatic hydrocarbons (PAHs, common compounds in urban grime). This new mechanism differs from the traditional mechanism, as it does not require the formation of the NO2 dimer. Instead, the enhanced electronic interaction between the UVA-light excited triplet state of PAHs and NO2-H2O/NO2-NH3-H2O significantly reduces the energy barrier and facilitates the exothermic formation of HONO from monomeric NO2. Furthermore, the performed experiments confirmed our theoretical findings and revealed that the synergistic effect from light-excited PAHs and NH3 boosts the HONO formation with determined HONO fluxes of 3.6 × 1010 molecules cm-2 s-1 at 60% relative humidity (RH) higher than any previously reported HONO fluxes. Intriguingly, light-induced NO2 to HONO conversion yield on authentic urban grime in presence of NH3 is unprecedented 130% at 60% RH due to the role of NH3 acting as a hydrogen carrier, facilitating the transfer of hydrogen from H2O to NO2. These results show that NH3-assisted UVA-light-induced NO2 to HONO conversion on urban surfaces can be a dominant source of HONO in the metropolitan area.
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Affiliation(s)
- Jiangping Liu
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou, 510640, China
- Chinese Academy of Science, Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, 650500, China
| | - Bai Li
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Huifan Deng
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou, 510640, China
- Chinese Academy of Science, Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yan Yang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
- Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory (Rongjiang Laboratory), Jieyang, 515200, China
- Synergy Innovation Institute of GDUT, Shantou, 515041, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou, 510640, China
- Chinese Academy of Science, Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou, 510640, China
- Chinese Academy of Science, Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
| | - Yongming Luo
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, 650500, China
- Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming, 650500, China
| | - Joseph S Francisco
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Lei Li
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Sasho Gligorovski
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Guangzhou, 510640, China
- Chinese Academy of Science, Center for Excellence in Deep Earth Science, Guangzhou, 510640, China
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6
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Li J, Wang J, Shen S, Chen R, Liu M, Dong F. Beyond Purification: Highly Efficient and Selective Conversion of NO into Ammonia by Coupling Continuous Absorption and Photoreduction under Ambient Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:5445-5452. [PMID: 36942694 DOI: 10.1021/acs.est.2c09669] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Although the selective catalytic reduction technology has been confirmed to be effective for nitrogen oxide (NOx) removal, green and sustainable NOx re-utilization under ambient conditions is still a great challenge. Herein, we develop an on-site system by coupling the continuous chemical absorption and photocatalytic reduction of NO in simulated flue gas (CNO = 500 ppm, GHSV = 18,000 h-1), which accomplishes an exceptional NO conversion into value-added ammonia with competitive conversion efficiency (89.05 ± 0.71%), ammonia production selectivity (95.58 ± 0.95%), and ammonia recovery efficiency (>90%) under ambient conditions. The anti-poisoning capacities, including the resistance against factors of H2O, SO2, and alkali/alkaline/heavy metals, are also achieved, which presents strong environmental practicability for treating NOx in flue gas. In addition, the critical roles of corresponding chemical absorption and catalytic reduction components are also revealed by in situ characterizations. The emerging strategy herein not only achieves a milestone efficiency for sustainable NO purification but also opens a new route for contaminant resourcing in the near future of carbon neutrality.
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Affiliation(s)
- Jieyuan Li
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
| | - Jielin Wang
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
| | - Shujie Shen
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
| | - Ruimin Chen
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
| | - Min Liu
- Hunan Joint International Research Center for Carbon Dioxide Resource Utilization, State Key Laboratory of Powder Metallurgy, School of Physical and Electronics, Central South University, Changsha 410083, China
| | - Fan Dong
- Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
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7
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Zhang Y, Xiao J, Zhang TC, Ouyang L, Yuan S. Synthesis of CuSiO3-loaded P-doped porous biochar derived from phytic acid-activated lemon peel for enhanced adsorption of NH3. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.120179] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Niu Y, Liu G, Xia H, Zhao X, Zhang G, Song L, Chen H. Controllable Synthesis of Enhanced Visible Light Responded Fe, N, Co Tri-TiO₂@MCM-41 Nanocomposites and Its Photocatalytic Performance. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2021; 21:5107-5119. [PMID: 33875096 DOI: 10.1166/jnn.2021.19363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A novel method for in situ synthesis of Fe, N, Co tri-TiO₂ (DT) loading on MCM-41 composite photocatalyst was proposed. Fe, N, Co tri-TiO₂@MCM-41 (DTM) with adsorption-degradation synergy was prepared by adjusting tetrabutyl titanate (TBOT) concentrations, the alcohol-water ratio in the atmosphere of the reaction chamber. The influence of preparation parameters on the texture structure, catalytic activity, and the synergism of adsorption and degradation of the DTM was discussed, the optimal parameters were determined. The DTM was characterized by XRD, TEM, BET, FT-IR, and UV-Vis. Besides, the DTM exhibited obvious redshift and visible catalytic activity compared with undoped TiO₂@MCM-41 (TM), which possessed excellent performance in the degradation of gaseous and liquid pollutants. The degradation rate of methylene blue (MB) and nitric oxide (NO) was 96.39% and 56.75%, respectively. Furthermore, DTM photocatalyst exhibited excellent reusability. The degradation efficiency of MB and NO after five cycles decreased by 4.54% and 5.89%, respectively.
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Affiliation(s)
- Yanhui Niu
- Engineering Research Center of Transportation Materials of Ministry of Education, School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China
| | - Guanyu Liu
- Engineering Research Center of Transportation Materials of Ministry of Education, School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China
| | - Huiyun Xia
- Engineering Research Center of Transportation Materials of Ministry of Education, School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China
| | - Xu Zhao
- Engineering Research Center of Transportation Materials of Ministry of Education, School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China
| | - Gengtong Zhang
- Engineering Research Center of Transportation Materials of Ministry of Education, School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China
| | - Lifang Song
- Engineering Research Center of Transportation Materials of Ministry of Education, School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China
| | - Huaxin Chen
- Engineering Research Center of Transportation Materials of Ministry of Education, School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China
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9
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Acosta Y, Gerber RB, Varner ME. Oxidation mechanism of ammonia in water clusters. Mol Phys 2021. [DOI: 10.1080/00268976.2021.1983057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Yanitza Acosta
- Chemistry and Biochemistry Department, Iona College, New Rochelle, NY, USA
| | - R. Benny Gerber
- Department of Chemistry, University of California, Irvine, CA, USA
- Department of Physical Chemistry and the Fritz Haber Research Center, The Hebrew University, Jerusalem, Israel
| | - Mychel E. Varner
- Chemistry and Biochemistry Department, Iona College, New Rochelle, NY, USA
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10
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Ma Q, Zhong C, Ma J, Ye C, Zhao Y, Liu Y, Zhang P, Chen T, Liu C, Chu B, He H. Comprehensive Study about the Photolysis of Nitrates on Mineral Oxides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:8604-8612. [PMID: 34132529 DOI: 10.1021/acs.est.1c02182] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nitrates formed on mineral dust through heterogeneous reactions in high NOx areas can undergo photolysis to regenerate NOx and potentially interfere in the photochemistry in the downwind low NOx areas. However, little is known about such renoxification processes. In this study, photolysis of various nitrates on different mineral oxides was comprehensively investigated in a flow reactor and in situ diffuse reflectance Fourier-transform infrared spectroscopy (in situ DRIFTS). TiO2 was found much more reactive than Al2O3 and SiO2 with both NO2 and HONO as the two major photolysis products. The yields of NO2 and HONO depend on the cation basicity of the nitrate salts or the acidity of particles. As such, NH4NO3 is much more productive than other nitrates like Fe(NO3)3, Ca(NO3)2, and KNO3. SO2 and water vapor promote the photodegradation by increasing the surface acidity due to the photoinduced formation of H2SO4/sulfate and H+, respectively. O2 enables the photo-oxidation of NOx to regenerate nitrate and thus inhibits the NOx yield. Overall, our results demonstrated that the photolysis of nitrate can be accelerated under complex air pollution conditions, which are helpful for understanding the transformation of nitrate and the nitrogen cycle in the atmosphere.
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Affiliation(s)
- Qingxin Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Cheng Zhong
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinzhu Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunxiang Ye
- Beijing Innovation Center for Engineering Science and Advanced Technology, State Key Joint Laboratory for Environmental Simulation and Pollution Control, Center for Environment and Health, and College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yaqi Zhao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuan Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tianzeng Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Chang Liu
- State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of China Meteorological Administration, Chinese Academy of Meteorological Sciences, Beijing 100081, China
| | - Biwu Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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11
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Wang T, Liu Y, Deng Y, Cheng H, Yang Y, Zhang L. Photochemical reaction of NO2 on photoactive mineral dust: Mechanism and irradiation intensity dependence. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2021.113319] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Diveky ME, Gleichweit MJ, Roy S, Signorell R. Shining New Light on the Kinetics of Water Uptake by Organic Aerosol Particles. J Phys Chem A 2021; 125:3528-3548. [PMID: 33739837 DOI: 10.1021/acs.jpca.1c00202] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The uptake of water vapor by various organic aerosols is important in a number of applications ranging from medical delivery of pharmaceutical aerosols to cloud formation in the atmosphere. The coefficient that describes the probability that the impinging gas-phase molecule sticks to the surface of interest is called the mass accommodation coefficient, αM. Despite the importance of this coefficient for the description of water uptake kinetics, accurate values are still lacking for many systems. In this Feature Article, we present various experimental techniques that have been evoked in the literature to study the interfacial transport of water and discuss the corresponding strengths and limitations. This includes our recently developed technique called photothermal single-particle spectroscopy (PSPS). The PSPS technique allows for a retrieval of αM values from three independent, yet simultaneous measurements operating close to equilibrium, providing a robust assessment of interfacial mass transport. We review the currently available data for αM for water on various organics and discuss the few studies that address the temperature and relative humidity dependence of αM for water on organics. The knowledge of the latter, for example, is crucial to assess the water uptake kinetics of organic aerosols in the Earth's atmosphere. Finally, we argue that PSPS might also be a viable method to better restrict the αM value for water on liquid water.
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Affiliation(s)
- Matus E Diveky
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Michael J Gleichweit
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Sandra Roy
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Ruth Signorell
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
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13
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Xiao L, Chen P, Yang W, Zhao X, Dong F. Photocatalytic reaction mechanisms at the gas–solid interface for environmental and energy applications. Catal Sci Technol 2021. [DOI: 10.1039/d1cy01776d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Five gas–solid photocatalytic reactions including the oxidation of NOx, VOCs and NH3, and reduction of CO2 and N2 are summarized. Besides, basic properties of gas molecules, their adsorption and activation, and various reaction pathways are analyzed.
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Affiliation(s)
- Lei Xiao
- Research Center for Environmental and Energy Catalysis, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313000, China
| | - Peng Chen
- The Center of New Energy Materials and Technology, School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, China
| | - Weiping Yang
- Research Center for Environmental and Energy Catalysis, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313000, China
| | - Xiaoli Zhao
- Research Center for Environmental and Energy Catalysis, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
| | - Fan Dong
- Research Center for Environmental and Energy Catalysis, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313000, China
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14
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Wang T, Liu Y, Deng Y, Cheng H, Yang Y, Feng Y, Zhang L, Fu H, Chen J. Photochemical Oxidation of Water-Soluble Organic Carbon (WSOC) on Mineral Dust and Enhanced Organic Ammonium Formation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15631-15642. [PMID: 33210909 DOI: 10.1021/acs.est.0c04616] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Water-soluble organic carbon (WSOC), which is closely related to biogenic emissions, is of great importance in the atmosphere for its ubiquitous existence and rich abundance. Levoglucosan, a typical WSOC, is usually considered to be stable and thus used as a tracer of biomass burning. However, we found that levoglucosan can be photo-oxidized on mineral dust, with formic acid, oxalic acid, glyoxylic acid, 2,3-dioxopropanoic acid, dicarbonic acid, performic acid, mesoxalaldehyde, 2-hydroxymalonaldehyde, carbonic formic anhydride, and 1,3-dioxolane-2,4-dione detected as main products. Further, we observed the heterogeneous uptake of NH3 promoted by the carboxylic acids stemming from the photocatalytic oxidation (PCO) of levoglucosan. The mineral-dust-initiated PCO of levoglucosan and enhanced heterogeneous uptake of NH3, which are highly influenced by irradiation and moisture conditions, were for the first time revealed. The reaction mechanisms and pathways were studied in detail by diffuse reflection infrared Fourier transform spectroscopy (DRIFTS), high-pressure photon ionization time-of-flight mass spectrometry (HPPI-ToF-MS) and flow reactor systems. Diverse WSOC constituents were studied as well, and the reactivity toward NH3 is related to the number of hydroxyl groups of the WSOC molecules. This work reveals a new precursor of secondary organic aerosols and provides experimental evidence of the existence of organic ammonium salts in atmospheric particles.
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Affiliation(s)
- Tao Wang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Yangyang Liu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Yue Deng
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Hanyun Cheng
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Yang Yang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Yiqing Feng
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Liwu Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
| | - Hongbo Fu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Jianmin Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, People's Republic of China
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Gopalan AI, Lee JC, Saianand G, Lee KP, Sonar P, Dharmarajan R, Hou YL, Ann KY, Kannan V, Kim WJ. Recent Progress in the Abatement of Hazardous Pollutants Using Photocatalytic TiO 2-Based Building Materials. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E1854. [PMID: 32948034 PMCID: PMC7559443 DOI: 10.3390/nano10091854] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/08/2020] [Accepted: 09/11/2020] [Indexed: 01/01/2023]
Abstract
Titanium dioxide (TiO2) has been extensively investigated in interdisciplinary research (such as catalysis, energy, environment, health, etc.) owing to its attractive physico-chemical properties, abundant nature, chemical/environmental stability, low-cost manufacturing, low toxicity, etc. Over time, TiO2-incorporated building/construction materials have been utilized for mitigating potential problems related to the environment and human health issues. However, there are challenges with regards to photocatalytic efficiency improvements, lab to industrial scaling up, and commercial product production. Several innovative approaches/strategies have been evolved towards TiO2 modification with the focus of improving its photocatalytic efficiency. Taking these aspects into consideration, research has focused on the utilization of many of these advanced TiO2 materials towards the development of construction materials such as concrete, mortar, pavements, paints, etc. This topical review focuses explicitly on capturing and highlighting research advancements in the last five years (mainly) (2014-2019) on the utilization of various modified TiO2 materials for the development of practical photocatalytic building materials (PBM). We briefly summarize the prospective applications of TiO2-based building materials (cement, mortar, concretes, paints, coating, etc.) with relevance to the removal of outdoor/indoor NOx and volatile organic compounds, self-cleaning of the surfaces, etc. As a concluding remark, we outline the challenges and make recommendations for the future outlook of further investigations and developments in this prosperous area.
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Affiliation(s)
- Anantha-Iyengar Gopalan
- Daegyeong Regional Infrastructure Technology Development Center, Kyungpook National University, Daegu 41566, Korea; (A.-I.G.); (K.-P.L.)
| | - Jun-Cheol Lee
- Department of Architecture, Seowon University, Cheongju 28674, Korea;
| | - Gopalan Saianand
- Global Centre for Environmental Remediation (GCER), Faculty of Science, The University of Newcastle, Callaghan, New South Wales 2308, Australia; (G.S.); (R.D.)
| | - Kwang-Pill Lee
- Daegyeong Regional Infrastructure Technology Development Center, Kyungpook National University, Daegu 41566, Korea; (A.-I.G.); (K.-P.L.)
| | - Prashant Sonar
- School of Chemistry and Physics, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia;
- Centre for Material Science, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
| | - Rajarathnam Dharmarajan
- Global Centre for Environmental Remediation (GCER), Faculty of Science, The University of Newcastle, Callaghan, New South Wales 2308, Australia; (G.S.); (R.D.)
| | - Yao-long Hou
- Department of Civil Engineering, Kyungpook National University, 80 Daehakro, Buk-gu, Daegu 41566, Korea;
| | - Ki-Yong Ann
- Department of Civil and Environmental Engineering, Hanyang University, Ansan 1588, Korea;
| | | | - Wha-Jung Kim
- Daegyeong Regional Infrastructure Technology Development Center, Kyungpook National University, Daegu 41566, Korea; (A.-I.G.); (K.-P.L.)
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Chen M, Zhang C, He H. Insights into Designing Photocatalysts for Gaseous Ammonia Oxidation under Visible Light. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:10544-10550. [PMID: 32786595 DOI: 10.1021/acs.est.0c02589] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Excessive emission of ammonia (NH3) gives rise to a number of negative effects on the environment and human health. Photocatalysis is an efficient method to eliminate gaseous NH3; however, photocatalytic oxidation (PCO) of NH3 in the visible light region has not been achieved to date. Herein, we test a set of typical visible-light-sensitive photocatalysts (N-TiO2, g-C3N4, and Ag3PO4) for NH3 oxidation and reveal for the first time that the semiconductor Ag3PO4 can harness visible light to realize ambient NH3 oxidation. Combining the activity testing results with the photochemical properties of samples, we confirm that photoexcited holes are responsible for triggering the initial key step of NH3 oxidation (NH3 to •NH2), and therefore, the redox potential of photoexcited holes plays the decisive role in the reaction. We propose that an active visible light photocatalyst for NH3 oxidation requires both a suitable band gap for visible light response and a low valence band edge associated with a high oxidation potential for activating NH3 to •NH2. Our findings provide new insights into the PCO of pollutants under visible light and will benefit future design of more efficient visible-light-sensitive photocatalysts.
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Affiliation(s)
- Min Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Changbin Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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17
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Vikrant K, Kim KH, Dong F, Giannakoudakis DA. Photocatalytic Platforms for Removal of Ammonia from Gaseous and Aqueous Matrixes: Status and Challenges. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02163] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Kumar Vikrant
- Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seoul 04763, Republic of Korea
| | - Ki-Hyun Kim
- Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seoul 04763, Republic of Korea
| | - Fan Dong
- Research Center for Environmental and Energy Catalysis, Institute of Fundamental and Frontier Sciences, School of Resources and Environment, University of Electronic Science and Technology of China, Chengdu 611731, China
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Abstract
Control of gaseous emissions from livestock operations is needed to ensure compliance with environmental regulations and sustainability of the industry. The focus of this research was to mitigate livestock odor emissions with UV light. Effects of the UV dose, wavelength, TiO2 catalyst, air temperature, and relative humidity were tested at lab scale on a synthetic mixture of nine odorous volatile organic compounds (VOCs) and real poultry manure offgas. Results show that it was feasible to control odorous VOCs with both photolysis and photocatalysis (synthetic VOCs mixture) and with photocatalysis (manure offgas). The treatment effectiveness R (defined as % conversion), was proportional to the light intensity for synthetic VOCs mixtures and followed an order of UV185+254 + TiO2 > UV254 + TiO2 > UV185+254; no catalyst > UV254; no catalyst. VOC conversion R > 80% was achieved when light energy was >~60 J L−1. The use of deep UV (UV185+254) improved the R, particularly when photolysis was the primary treatment. Odor removal up to ~80% was also observed for a synthetic VOCs mixture, and actual poultry manure offgas. Scale-up studies are warranted.
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19
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Chattopadhyay S, Bysakh S, Mishra PM, De G. In Situ Synthesis of Mesoporous TiO 2 Nanofibers Surface-Decorated with AuAg Alloy Nanoparticles Anchored by Heterojunction Exhibiting Enhanced Solar Active Photocatalysis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:14364-14375. [PMID: 31593629 DOI: 10.1021/acs.langmuir.9b02361] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We designed an electrospinning synthesis protocol to obtain in situ, the mesoporous TiO2 nanofibers, which are surface-decorated with plasmonic AuAg nanoparticles (AuAg-mTNF-H). Such alloy nanoparticles are found to be partially exposed on the surface of the nanofibers. Characterization by HRTEM and EDS confirmed the formation of 1:1 AuAg alloy nanoparticles on the surface of TiO2 nanofibers with heterojunction at the interfaces. On the basis of electron microscopic characterization, we proposed that, during the formation of the nanofibers, the incorporated metal ions with surface capping of negative charges migrated toward the outer surface of the nascent fibers under the influence of high positive voltage required for electrospinning. As a result, after the subsequent thermal treatment, the crystallization of TiO2 nanofibers and the formation of alloy nanoparticles took place, leading to the formation of a deep heterojunction through partial embedment of the nanoparticles. The formation of AuAg alloy also restricted the oxidation of Ag, thus making the nanoparticles highly stable in ambient condition. Accordingly, such unique AuAg-mTNF-H photocatalyst shows strong light absorption property covering the entire range of visible wavelengths with stability. The solar light harvesting property of AuAg-mTNF-H was verified by monitoring solar light induced H2 evolution via water splitting and photodecomposition of MB. In both the cases AuAg-mTNF-H showed excellent H2 evolution and photodecomposition of dye.
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Affiliation(s)
- Shreyasi Chattopadhyay
- CSIR-Central Glass and Ceramic Research Institute , 196, Raja S. C. Mullick Road , Kolkata 700032 , India
| | - Sandip Bysakh
- CSIR-Central Glass and Ceramic Research Institute , 196, Raja S. C. Mullick Road , Kolkata 700032 , India
| | - Pravat Manjari Mishra
- Environment & Sustainability Department , CSIR-Institute of Minerals and Materials Technology , Bhubaneswar 751013 , Odisha , India
| | - Goutam De
- Institute of Nano Science and Technology , Mohali 160062 , Punjab , India
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20
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He X, Zhang YH. Influence of relative humidity on SO 2 oxidation by O 3 and NO 2 on the surface of TiO 2 particles: Potential for formation of secondary sulfate aerosol. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 219:121-128. [PMID: 31030039 DOI: 10.1016/j.saa.2019.04.046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/14/2019] [Accepted: 04/17/2019] [Indexed: 06/09/2023]
Abstract
The heterogeneous reactions of SO2/O3 and SO2/NO2 with TiO2 particles were studied as a function of relative humidities (RHs). An in situ microscopic Fourier transform infrared (micro-FTIR) spectrometer was used to monitor the reaction kinetics. Rapid conversion of SO2 to sulfate occurs on the surface of TiO2 particles in the presence of O3 or NO2, which is sensitive to RHs. For unreacted (fresh) particles, the uptake coefficients for SO2 in initial stage are both obviously enhanced over four times with the increasing RH from ~4% to ~85%. Moreover, the uptake coefficient in the system of SO2/O3 is about 40% higher than that of SO2/NO2 on TiO2 particles at the similar RH conditions. For TiO2 after exposure to SO2/O3 or SO2/NO2 (sulfated) particles, the uptake coefficients for SO2 in moisture absorption stage are all higher than that on fresh particles in initial stage at the similar RH, indicating rapid mixture gases adsorption with particle hygroscopic growth. The high production of the secondary sulfate for heterogeneous reaction of mixture gases on TiO2 surface from arid region to humid region provides new insights for better understanding the severe haze under the humid condition.
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Affiliation(s)
- Xiang He
- College of Resource and Environment Sciences, Xinjiang University, Urumqi 830046, PR China; Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, PR China
| | - Yun-Hong Zhang
- Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, PR China.
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21
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Brzicova T, Sikorova J, Milcova A, Vrbova K, Klema J, Pikal P, Lubovska Z, Philimonenko V, Franco F, Topinka J, Rossner P. Nano-TiO2 stability in medium and size as important factors of toxicity in macrophage-like cells. Toxicol In Vitro 2019; 54:178-188. [DOI: 10.1016/j.tiv.2018.09.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 08/30/2018] [Accepted: 09/26/2018] [Indexed: 10/28/2022]
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22
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Dai C, Qiu Y, He Y, Zhang Q, Liu R, Du J, Tao C. Controlled synthesis of a Bi2O3–CuO catalyst for selective electrochemical reduction of CO2 to formate. NEW J CHEM 2019. [DOI: 10.1039/c8nj05205k] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The electro-reduction of CO2 to produce energy sources has been considered as a visionary pathway with the help of renewable electricity, which can achieve carbon neutrality and mitigate global warming.
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Affiliation(s)
- Chaoneng Dai
- College of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- P. R. China
| | - Yue Qiu
- College of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- P. R. China
- Chongqing Academy of Metrology and Quality Inspection
| | - Yu He
- College of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- P. R. China
| | - Qiang Zhang
- College of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- P. R. China
| | - Renlong Liu
- College of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- P. R. China
| | - Jun Du
- College of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- P. R. China
| | - Changyuan Tao
- College of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- P. R. China
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The Paleomineralogy of the Hadean Eon Revisited. Life (Basel) 2018; 8:life8040064. [PMID: 30562935 PMCID: PMC6315770 DOI: 10.3390/life8040064] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/03/2018] [Accepted: 12/07/2018] [Indexed: 11/17/2022] Open
Abstract
A preliminary list of plausible near-surface minerals present during Earth’s Hadean Eon (>4.0 Ga) should be expanded to include: (1) phases that might have formed by precipitation of organic crystals prior to the rise of predation by cellular life; (2) minerals associated with large bolide impacts, especially through the generation of hydrothermal systems in circumferential fracture zones; and (3) local formation of minerals with relatively oxidized transition metals through abiological redox processes, such as photo-oxidation. Additional mineral diversity arises from the occurrence of some mineral species that form more than one ‘natural kind’, each with distinct chemical and morphological characteristics that arise by different paragenetic processes. Rare minerals, for example those containing essential B, Mo, or P, are not necessary for the origins of life. Rather, many common minerals incorporate those and other elements as trace and minor constituents. A rich variety of chemically reactive sites were thus available at the exposed surfaces of common Hadean rock-forming minerals.
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Synthesis of Al-MCM-41@Ag/TiO2 Nanocomposite and Its Photocatalytic Activity for Degradation of Dibenzothiophene. J CHEM-NY 2018. [DOI: 10.1155/2018/8418605] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mesoporous Al-MCM-41@Ag/TiO2 nanocomposites were synthesized successfully by combining the sol-gel method and hydrothermal treatment, using titanium isopropoxide (TTIP), AgNO3, and Vietnamese bentonite as precursors of Ti, Ag, and Si, respectively. The synthesized materials were well characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption isotherm measurements, energy dispersive X-ray spectroscopy (EDX), UV-visible diffuse reflectance spectroscopy (UV-Vis/DRS), and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity was evaluated by the photodegradation of dibenzothiophene (DBT) under both UV and visible light irradiation. MCM-41@Ag/TiO2 catalyst exhibited high catalytic activity for the oxidative desulfurization (ODS) of DBT reaching almost 100% conversions at 50°C after 2 h under UV and visible light irradiations. The significant enhanced degradation of DBT over Al-MCM-41@Ag/TiO2 might be due to the synergy effects of high surface area of MCM-41, well-distributed TiO2 anatase, and reduced electron-hole recombination rates due to the dispersion of Ag nanoparticles.
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25
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Dong X, Deng G, Wu Z, Xu J, Lu B, Trabelsi T, Francisco JS, Zeng X. Spectroscopic Identification of H 2
NSO and syn
- and anti
-HNSOH Radicals. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201802738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xuelin Dong
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Guohai Deng
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Zhuang Wu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Jian Xu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Bo Lu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Tarek Trabelsi
- Department of Chemistry; University of Nebraska-Lincoln; Lincoln NE 68588 USA
| | - Joseph S. Francisco
- Department of Chemistry; University of Nebraska-Lincoln; Lincoln NE 68588 USA
| | - Xiaoqing Zeng
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
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26
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Dong X, Deng G, Wu Z, Xu J, Lu B, Trabelsi T, Francisco JS, Zeng X. Spectroscopic Identification of H2
NSO and syn
- and anti
-HNSOH Radicals. Angew Chem Int Ed Engl 2018; 57:7513-7517. [DOI: 10.1002/anie.201802738] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Xuelin Dong
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Guohai Deng
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Zhuang Wu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Jian Xu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Bo Lu
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
| | - Tarek Trabelsi
- Department of Chemistry; University of Nebraska-Lincoln; Lincoln NE 68588 USA
| | - Joseph S. Francisco
- Department of Chemistry; University of Nebraska-Lincoln; Lincoln NE 68588 USA
| | - Xiaoqing Zeng
- College of Chemistry, Chemical Engineering and Materials Science; Soochow University; Suzhou 215123 China
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27
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Xie B, Luo H, Tang Q, Du J, Liu Z, Tao C. The black rock series supported SCR catalyst for NO x removal. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:21761-21769. [PMID: 28766147 DOI: 10.1007/s11356-017-9622-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
Black rock series (BRS) is of great potential for their plenty of valued oxides which include vanadium, iron, alumina and silica oxides, etc. BRS was used for directly preparing of selective catalytic reduction (SCR) catalyst by modifying its surface texture with SiO2-TiO2 sols and regulating its catalytic active constituents with V2O5 and MoO3. Consequently, 90% NO removal ratio was obtained within 300-400 °C over the BRS-based catalyst. The structure and properties of the BRS-based catalyst were characterized by the techniques of N2 adsorption-desorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), H2-temperature programmed reduction (H2-TPR), and NH3-temperature programmed desorption (NH3-TPD). The results revealed that the BRS-based catalyst possesses favorable properties for NO x removal, including highly dispersed active components, abundant surface-adsorbed oxygen Oα, well redox property, and numerous Brønsted acid sites. Particularly, the BRS-based catalyst exhibited considerable anti-poisoning performance compared with commercial TiO2-based catalyst. The former catalyst shows a NO conversion surpassing 80% from 300 to 400 °C for potassium poisoning, and a durability of SO2 and H2O exceeding 85% at temperatures from 300 to 450 °C.
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Affiliation(s)
- Bin Xie
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering (Chongqing), Chongqing University, Chongqing, 400044, China
| | - Hang Luo
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering (Chongqing), Chongqing University, Chongqing, 400044, China
| | - Qing Tang
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering (Chongqing), Chongqing University, Chongqing, 400044, China
| | - Jun Du
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering (Chongqing), Chongqing University, Chongqing, 400044, China.
| | - Zuohua Liu
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering (Chongqing), Chongqing University, Chongqing, 400044, China
| | - Changyuan Tao
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering (Chongqing), Chongqing University, Chongqing, 400044, China.
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28
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Emissions and Possible Environmental Implication of Engineered Nanomaterials (ENMs) in the Atmosphere. ATMOSPHERE 2017. [DOI: 10.3390/atmos8050084] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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29
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Stewart KME, Penlidis A. Designing polymeric sensing materials: what are we doing wrong? POLYM ADVAN TECHNOL 2016. [DOI: 10.1002/pat.3893] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Katherine M. E. Stewart
- Institute for Polymer Research, Department of Chemical Engineering; University of Waterloo; 200 University Avenue West Waterloo Ontario N2L 3G1 Canada
| | - Alexander Penlidis
- Institute for Polymer Research, Department of Chemical Engineering; University of Waterloo; 200 University Avenue West Waterloo Ontario N2L 3G1 Canada
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30
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Kebede MA, Bish DL, Losovyj Y, Engelhard MH, Raff JD. The Role of Iron-Bearing Minerals in NO2 to HONO Conversion on Soil Surfaces. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:8649-60. [PMID: 27409359 DOI: 10.1021/acs.est.6b01915] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Nitrous acid (HONO) accumulates in the nocturnal boundary layer where it is an important source of daytime hydroxyl radicals. Although there is clear evidence for the involvement of heterogeneous reactions of NO2 on surfaces as a source of HONO, mechanisms remain poorly understood. We used coated-wall flow tube measurements of NO2 reactivity on environmentally relevant surfaces (Fe (hydr)oxides, clay minerals, and soil from Arizona and the Saharan Desert) and detailed mineralogical characterization of substrates to show that reduction of NO2 by Fe-bearing minerals in soil can be a more important source of HONO than the putative NO2 hydrolysis mechanism. The magnitude of NO2-to-HONO conversion depends on the amount of Fe(2+) present in substrates and soil surface acidity. Studies examining the dependence of HONO flux on substrate pH revealed that HONO is formed at soil pH < 5 from the reaction between NO2 and Fe(2+)(aq) present in thin films of water coating the surface, whereas in the range of pH 5-8 HONO stems from reaction of NO2 with structural iron or surface complexed Fe(2+) followed by protonation of nitrite via surface Fe-OH2(+) groups. Reduction of NO2 on ubiquitous Fe-bearing minerals in soil may explain HONO accumulation in the nocturnal boundary layer and the enhanced [HONO]/[NO2] ratios observed during dust storms in urban areas.
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Affiliation(s)
| | | | | | - Mark H Engelhard
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory , Richland, Washington 99354, United States
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31
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Yang W, He H, Ma Q, Ma J, Liu Y, Liu P, Mu Y. Synergistic formation of sulfate and ammonium resulting from reaction between SO2 and NH3 on typical mineral dust. Phys Chem Chem Phys 2016; 18:956-64. [DOI: 10.1039/c5cp06144j] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A synergistic effect between SO2 and NH3 on typical mineral dust.
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Affiliation(s)
- Weiwei Yang
- State Key Joint Laboratory of Environment Simulation and Pollution Control
- Research Center for Eco-Environmental Sciences
- Chinese Academy of Sciences
- Beijing 100085
- China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control
- Research Center for Eco-Environmental Sciences
- Chinese Academy of Sciences
- Beijing 100085
- China
| | - Qingxin Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control
- Research Center for Eco-Environmental Sciences
- Chinese Academy of Sciences
- Beijing 100085
- China
| | - Jinzhu Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control
- Research Center for Eco-Environmental Sciences
- Chinese Academy of Sciences
- Beijing 100085
- China
| | - Yongchun Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control
- Research Center for Eco-Environmental Sciences
- Chinese Academy of Sciences
- Beijing 100085
- China
| | - Pengfei Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control
- Research Center for Eco-Environmental Sciences
- Chinese Academy of Sciences
- Beijing 100085
- China
| | - Yujing Mu
- State Key Joint Laboratory of Environment Simulation and Pollution Control
- Research Center for Eco-Environmental Sciences
- Chinese Academy of Sciences
- Beijing 100085
- China
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32
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Asatryan R, Ruckenstein E. Effect of “Reducible” Titania Promotion on the Mechanism of H-Migration in Pd/SiO2 Clusters. Catal Letters 2015. [DOI: 10.1007/s10562-015-1642-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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33
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Liu B, Du J, Lv X, Qiu Y, Tao C. Washcoating of cordierite honeycomb with vanadia–tungsta–titania mixed oxides for selective catalytic reduction of NO with NH3. Catal Sci Technol 2015. [DOI: 10.1039/c4cy01179a] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The application of monolithic coated catalysts to NOx abatement is a crucial issue for practical applications to enhance the mechanical strength, economize the cost, facilitate recycling etc., compared with the conventional monolithic extrusive catalysts.
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Affiliation(s)
- Bo Liu
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization
- College of Chemistry and Chemical Engineering (Chongqing)
- Chongqing University
- Chongqing 400044
- China
| | - Jun Du
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization
- College of Chemistry and Chemical Engineering (Chongqing)
- Chongqing University
- Chongqing 400044
- China
| | - Xiaowei Lv
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization
- College of Chemistry and Chemical Engineering (Chongqing)
- Chongqing University
- Chongqing 400044
- China
| | - Yue Qiu
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization
- College of Chemistry and Chemical Engineering (Chongqing)
- Chongqing University
- Chongqing 400044
- China
| | - Changyuan Tao
- Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization
- College of Chemistry and Chemical Engineering (Chongqing)
- Chongqing University
- Chongqing 400044
- China
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Kim J, Kim J. Arsenite oxidation-enhanced photocatalytic degradation of phenolic pollutants on platinized TiO2. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:13384-13391. [PMID: 25329010 DOI: 10.1021/es504082r] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The effect of As(III) on the photocatalytic degradation of phenolic pollutants such as 4-chlorophenol (4-CP) and bisphenol A (BPA) in a suspension of platinized TiO2 (Pt/TiO2) was investigated. In the presence of As(III), the photocatalytic degradation of 4-CP and BPA was significantly enhanced, and the simultaneous oxidation of As(III) to As(V) was also achieved. This positive effect of As(III) on the degradation of phenolic pollutants is attributed to the adsorption of As(V) (generated from As(III) oxidation) on the surface of Pt/TiO2, which facilitates the production of free OH radicals ((•)OHf) that are more reactive than surface-bound OH radicals ((•)OHs) toward phenolic pollutants. The generation of (•)OHf was indirectly verified by using coumarin as an OH radical trapper and comparing the yields of coumarin--OH adduct (i.e., 7-hydroxycoumarin) formed in the absence and presence of As(V). In repeated cycles of 4-CP degradation, the degradation efficiency of 4-CP gradually decreased in the absence of As(III), whereas it was mostly maintained in the presence of As(III), which was either initially present or repeatedly injected at the beginning of each cycle. The positive effect of As(III) on 4-CP degradation was observed over a wide range of As(III) concentrations (up to mM levels) with Pt/TiO2. However, a high concentration of As(III) (hundreds of μM) inhibited the degradation of 4-CP with bare TiO2. Therefore, Pt/TiO2 can be proposed as a practical photocatalyst for the simultaneous oxidation of phenolic pollutants and As(III) in industrial wastewaters.
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Affiliation(s)
- Jaesung Kim
- Department of Environmental Sciences and Biotechnology, Hallym University , Chuncheon, Gangwon-do 200-702, South Korea
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35
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Scharko NK, Berke AE, Raff JD. Release of nitrous acid and nitrogen dioxide from nitrate photolysis in acidic aqueous solutions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:11991-12001. [PMID: 25271384 DOI: 10.1021/es503088x] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Nitrate (NO3(-)) is an abundant component of aerosols, boundary layer surface films, and surface water. Photolysis of NO3(-) leads to NO2 and HONO, both of which play important roles in tropospheric ozone and OH production. Field and laboratory studies suggest that NO3¯ photochemistry is a more important source of HONO than once thought, although a mechanistic understanding of the variables controlling this process is lacking. We present results of cavity-enhanced absorption spectroscopy measurements of NO2 and HONO emitted during photodegradation of aqueous NO3(-) under acidic conditions. Nitrous acid is formed in higher quantities at pH 2-4 than expected based on consideration of primary photochemical channels alone. Both experimental and modeled results indicate that the additional HONO is not due to enhanced NO3(-) absorption cross sections or effective quantum yields, but rather to secondary reactions of NO2 in solution. We find that NO2 is more efficiently hydrolyzed in solution when it is generated in situ during NO3(-) photolysis than for the heterogeneous system where mass transfer of gaseous NO2 into bulk solution is prohibitively slow. The presence of nonchromophoric OH scavengers that are naturally present in the environment increases HONO production 4-fold, and therefore play an important role in enhancing daytime HONO formation from NO3(-) photochemistry.
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Affiliation(s)
- Nicole K Scharko
- School of Public and Environmental Affairs and the Department of Chemistry, Indiana University , Bloomington, Indiana 47405-2204, United States
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36
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Tang MJ, Camp JCJ, Rkiouak L, McGregor J, Watson IM, Cox RA, Kalberer M, Ward AD, Pope FD. Heterogeneous Interaction of SiO2 with N2O5: Aerosol Flow Tube and Single Particle Optical Levitation–Raman Spectroscopy Studies. J Phys Chem A 2014; 118:8817-27. [DOI: 10.1021/jp506753c] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- M. J. Tang
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Department
of Earth Sciences, University of Bristol, Wills Memorial Building, Bristol BS8 1RJ, United Kingdom
| | - J. C. J. Camp
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, United Kingdom
| | - L. Rkiouak
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, United Kingdom
| | - J. McGregor
- Department
of Chemical and Biological Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD, United Kingdom
| | - I. M. Watson
- Department
of Earth Sciences, University of Bristol, Wills Memorial Building, Bristol BS8 1RJ, United Kingdom
| | - R. A. Cox
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - M. Kalberer
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - A. D. Ward
- Central
Laser Facility, STFC, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX, United Kingdom
| | - F. D. Pope
- School
of
Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston,
Birmingham B15 2TT, United Kingdom
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37
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In situ IR studies of selective catalytic reduction of NO with NH3 on Ce-Ti amorphous oxides. CHINESE JOURNAL OF CATALYSIS 2014. [DOI: 10.1016/s1872-2067(14)60154-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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38
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Donaldson MA, Berke AE, Raff JD. Uptake of gas phase nitrous acid onto boundary layer soil surfaces. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:375-83. [PMID: 24328088 DOI: 10.1021/es404156a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Nitrous acid (HONO) is an important OH radical source that is formed on both ground and aerosol surfaces in the well-mixed boundary layer. Large uncertainties remain in quantifying HONO sinks and determining the mechanism of HONO uptake onto surfaces. We report here the first laboratory determination of HONO uptake coefficients onto actual soil under atmospheric conditions using a coated-wall flow tube coupled to a highly sensitive chemical ionization mass spectrometer (CIMS). Uptake coefficients for HONO decrease with increasing RH from (2.5 ± 0.4) × 10(-4) at 0% RH to (1.1 ± 0.4) × 10(-5) at 80% RH. A kinetics model of competitive adsorption of HONO and water onto the particle surfaces fits the dependence of the HONO uptake coefficients on the initial HONO concentration and relative humidity. However, a multiphase resistor model based on the physical and chemical processes affecting HONO uptake is more flexible as it accounts for the pH dependence of HONO uptake and bulk diffusion in the soil matrix. Fourier transform infrared (FTIR) spectrometry and cavity-enhanced absorption spectroscopy (CEAS) studies indicate that NO and N2O (16% and 13% yield, respectively) rather than NO2 are the predominant gas phase products, while NO2(-) and NO3(-) were detected on the surface post-exposure. Results are compared to uptake coefficients inferred from models and field measurements, and the atmospheric implications are discussed.
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Affiliation(s)
- Melissa A Donaldson
- School of Public and Environmental Affairs and Department of Chemistry, Indiana University , Bloomington, Indiana 47405-2204, United States
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