作者：
Chengliang Mao;Jiaxian Wang;Yunjie Zou;Yanbiao Shi;Camilo J. Viasus;...
期刊：
Journal of the American Chemical Society,2023年145(24):13134-13146 ISSN：0002-7863
通讯作者：
Lirong Zheng<&wdkj&>Lizhi Zhang<&wdkj&>Geoffrey A. Ozin
作者机构：
[Yunjie Zou; Meiqi Li; Huan Shang; Zhilin Li] Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China;[Joel Y. Y. Loh; Nazir P. Kherani] Department of Materials Science and Engineering, University of Toronto, Toronto, Ontario M5S 3E4, Canada;[Yanjiang Liu] Ontario Centre for the Characterization of Advanced Materials, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, Canada;[Camilo J. Viasus; Meikun Xia; Shufang Ji; Mireille Ghoussoub; Yang-Fan Xu; Jessica Ye; Geoffrey A. Ozin] Materials Chemistry and Nanochemistry Research Group, Solar Fuels Cluster, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada;[Lirong Zheng] Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China
通讯机构：
[Lirong Zheng] B;[Lizhi Zhang] K;[Geoffrey A. Ozin] M;Materials Chemistry and Nanochemistry Research Group, Solar Fuels Cluster, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada<&wdkj&>Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China<&wdkj&>Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China<&wdkj&>School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
摘要：
Stable metal nitrides (MN) are promising materials to fit the future "green" ammonia-hydrogen nexus. Either through catalysis or chemical looping, the reductive hydrogenation of MN to MN(1-x) is a necessary step to generate ammonia. However, encumbered by the formation of kinetically stable M-NH(1─3) surface species, this reduction step remains challenging under mild conditions. Herein, we discovered that deleterious Ti-NH(1─3) accumulation on TiN can be circumvented photochemically with supported single atoms and clusters of platinum (Pt(1)-Pt(n)) under N(2)-H(2) conditions. The photochemistry of TiN selectively promoted Ti-NH formation, while Pt(1)-Pt(n) effectively transformed any formed Ti-NH into free ammonia. The generated ammonia was found to originate mainly from TiN reduction with a minor contribution from N(2) activation. The knowledge accrued from this fundamental study could serve as a springboard for the development of MN materials for more efficient ammonia production to potentially disrupt the century-old fossil-powered Haber-Bosch process.
摘要：
In this study, we demonstrate that the addition of ascorbate can lower the conversion percentage of H2O2 to O-2 from 71% to 11%, and thus increase the conversion percentage of H2O2 to (OH)-O-center dot from 11% to 82% on goethite within 3 h. This greatly enhanced production of (OH)-O-center dot could be attributed to the efficient Fe(III)/Fe(II) redox cycle accelerated by ascorbate, which produced abundant Fe(II) confined on the goethite surface, favoring the con-version of H2O2 to (OH)-O-center dot. Meanwhile, the decreased surface Fe(III) of goethite strongly inhibited the conversion of H2O2 to O-2. These findings can clarify the quantitative influence of ascorbate on the H2O2 decomposition process over the iron mineral surface, and thus deepen the understanding of heterogeneous Fenton reaction mechanism during organic containment treatment.
通讯机构：
[Liu, Xiao] C;Cent China Normal Univ, Coll Chem, Inst Environm & Appl Chem, Key Lab Pesticide & Chem Biol,Minist Educ, Wuhan 430079, Peoples R China.
关键词：
Hematite;Oxalate;Photodissociation;Interfacial reaction;Reactive oxygen species
摘要：
Oxalates, together with iron (hydr)oxides, play important roles in environmental decontamination by photo-chemical generation of reactive oxygen species (ROS). However, comprehending reaction mechanism about photolytic behaviors across solid-liquid interface is scarce. Here, the photochemical properties of hematite-oxalate system were investigated from complexation, photolysis, and ROS generation tests. Results implied adsorbed oxalate on hematite surface was detached via non-reductive dissolution by irradiating light. Then, the photolysis of Fe(III)-oxalate complexes on hematite surface or dissolved in solution was followed by photodissociation mechanism, in which per Fe(III)-oxalate complex led to two CO2 center dot- formation. Moreover, O-2(center dot-)/(OOH)-O-center dot and (OH)-O-center dot amounts induced by photodissociation mechanism were much higher than that by classic intramolecular ligand-to-metal charge transfer mechanism in Fe3+-Ox homogeneous system. The photo-degradation and mineralization of sulfadimidine (5 mg/L) reached 95 % and 59 % within 2 h using hematite-Ox system. These findings can help in implementing environmental remediation by utilizing iron (hydr)oxides and oxalate in natural environment.
通讯机构：
[Ai, ZH; Zhang, LZ] C;Cent China Normal Univ, Coll Chem, Inst Environm & Appl Chem, Key Lab Pesticide & Chem Biol,Minist Educ, Wuhan 430079, Peoples R China.
摘要：
The purification of water and air by semiconductor photocatalysis is a rapidly growing area for academic research and industrial innovation, featured with ambient removal of organic or inorganic pollutants by using solar light as the energy source and atmospheric O(2) as the green oxidant. Both charge transfer and energy transfer from excited photocatalysts can overcome the spin-forbidden nature of O(2). Layered bismuth oxyhalides are a new group of two-dimensional photocatalysts with an appealing geometric and surface structure that allows the dynamic and selective tuning of O(2) activation at the surface molecular level. In this Feature Article, we specifically summarize our recent progress in selective O(2) activation by engineering surface structures of bismuth oxyhalides. Then, we demonstrate selective photocatalytic O(2) activation of bismuth oxyhalides for environmental control, including water decontamination, volatile organic compound oxidation and nitrogen oxide removal, as well as selective catalytic oxidations. Challenges and opportunities regarding the design of photocatalysts with satisfactory performance for potential environmental control applications are also presented.
摘要：
Herein, sulfur vacancies in magnetic greigite (SVs-Fe3S4) nanosheets were synthesized by a one-step solvothermal method by adjusting the ethylene glycol: water ratio. Electron paramagnetic resonance spectroscopy (EPR) and X-ray photoelectron spectroscopy (XPS) revealed that SV-rich Fe3S4 and SV-poor Fe3S4 were acquired using 100% ethylene glycol and 100% water as solvent, respectively. A peroxidase-like activity assay demonstrated that maximum reaction rates for H2O2-mediated oxidation of 3,3',5,5'-tetramethyl-benzidine (TMB) catalyzed by the SV-rich Fe3S4 was 2.3 times higher than SV-poor Fe3S4. Density functional theory (DFT) calculations and reactive oxygen species (ROS) detection confirmed that the enhanced peroxidase-like activity by SV-rich Fe3S4 was attributed to efficient adsorption of H2O2 and subsequent decomposition to hydroxyl radicals (center dot OH) on the SVs sites of Fe3S4. The SV-rich Fe3S4 nanozyme was employed to develop a simple, highly sensitive and selective assay for glucose detection with a linear range of 0.5-150 mu M and a detection limit of 0.1 mu M (S/N = 3). A smartphone application (App) was designed and applied to efficiently detect serum glucose with the integrated analytical system based on the SV-rich Fe3S4. These new findings highlight the important role of surface defects in nanozymes on generating peroxidase-like activity for glucose detection in point-of-care diagnosis. (C) 2020 Elsevier B.V. All rights reserved.
摘要：
Rational engineering of oxygen vacancy (V-O) at atomic precision is the key to comprehensively understanding the oxygen chemistry of oxide materials for catalytic oxidations. Here, we demonstrate that V-O can be spatially confined on the surface through a sophisticated surface hydrogen bond (HB) network. The HB network is constructed between a hydroxyl-rich BiOCl surface and polyprotic phosphoric acid, which remarkably decreases the formation energy of surface V-O by selectively weakening the metal-oxygen bonds in a short range. Thus, surface-confined V-O enables us to unambiguously distinguish the intrafacial and suprafacial oxygen species associated with NO oxidation in two classical catalytic systems. Unlike randomly distributed bulk V-O that benefits the thermocatalytic NO oxidation and lattice O diffusion by the dominant intrafacial mechanism, surface V-O is demonstrated to favor the photocatalytic NO oxidation through a suprafacial scheme by energetically activating surface O-2, which should be attributed to the spatial confinement nature of surface V-O. (C) 2020 Science China Press. Published by Elsevier B.V. and Science China Press. All rights reserved.
期刊：
Journal of the American Chemical Society,2020年142(15):7036-7046 ISSN：0002-7863
通讯作者：
Zhang, Lizhi;Yu, Jimmy C.
作者机构：
[Xu, Liangpang; Lei, Fengcai; Chan, Alice W. M.; Li, Lejing; Liu, Yang; Yu, Jimmy C.; Li, Jie] Chinese Univ Hong Kong, Dept Chem, Shatin, Hong Kong, Peoples R China.;[Quan, Fengjiao; Zhang, Lizhi; Shi, Yanbiao; Mao, Chengliang; Zhan, Guangming] Cent China Normal Univ, Coll Chem, Inst Environm & Appl Chem, Minist Educ,Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.;[Wang, Jianfang; Yang, Jianhua] Chinese Univ Hong Kong, Dept Phys, Shatin, Hong Kong, Peoples R China.;[Wong, Po Keung; Wang, Bo] Chinese Univ Hong Kong, Sch Life Sci, Shatin, Hong Kong, Peoples R China.;[Du, Yi; Dou, Shi-Xue] Univ Wollongong, AIIM, ISEM, Wollongong, NSW 2500, Australia.
通讯机构：
[Zhang, Lizhi; Yu, Jimmy C.] C;Cent China Normal Univ, Coll Chem, Inst Environm & Appl Chem, Minist Educ,Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.;Chinese Univ Hong Kong, Dept Chem, Shatin, Hong Kong, Peoples R China.
摘要：
The limitations of the Haber-Bosch reaction, particularly high-temperature operation, have ignited new interests in low-temperature ammonia-synthesis scenarios. Ambient N-2 electroreduction is a compelling alternative but is impeded by a low ammonia production rate (mostly <10 mmol g(cat)(-1) h(-1)), a small partial current density (<1 mA cm(-2)), and a high-selectivity hydrogen-evolving side reaction. Herein, we report that room-temperature nitrate electroreduction catalyzed by strained ruthenium nanoclusters generates ammonia at a higher rate (5.56 g(cat)(-1) h(-1)) than the Haber- Bosch process. The primary contributor to such performance is hydrogen radicals, which are generated by suppressing hydrogen-hydrogen dimerization during water splitting enabled by the tensile lattice strains. The radicals expedite nitrate-to-ammonia conversion by hydrogenating intermediates of the rate-limiting steps at lower kinetic barriers. The strained nanostructures can maintain nearly 100% ammonia-evolving selectivity at >120 mA cm(-2) current densities for 100 h due to the robust subsurface Ru-O coordination. These findings highlight the potential of nitrate electroreduction in real-world, low-temperature ammonia synthesis.
通讯机构：
[Peng, X; Zhang, LZ] C;Cent China Normal Univ, Coll Chem, Inst Environm & Appl Chem, Key Lab Pesticide & Chem Biol,Minist Educ, Wuhan 430079, Peoples R China.
关键词：
Zero-valent iron;FeC2O4 center dot 2H(2)O shell;Cr(VI) removal;Proton transfer;Surface-bound Fe2+
摘要：
In this study, we coated a high proton conducive shell on the zero-valent iron (ZVI) surface by mechanically ball-milling ZVI with oxalic acid dihydrate (OX-ZVI), and demonstrated that the generated FeC2O4 center dot 2H(2)O shell dramatically improved the Cr(VI) removal rate of ZVI by about 15-80 times. Owing to a higher proton conductivity of FeC2O4 center dot 2H(2)O shell than that of Fe2O3 shell, proton could easily transfer through FeC2O4 center dot 2H(2)O shell into iron core and be reduced to center dot H, accompanying with fast surface-bound Fe2+ generation, resulting in high efficiency of Cr(VI) removal in a wide pH range. Meanwhile, the removed Cr(VI) was deposited on OX-ZVI surface in the formation of FexCr1-x(OH)(3) composites, accompanied by the appearance of typical hollow structure derived from iron core dissolution. This study clarifies the significance of proton transfer on the reactivity of zero-valent iron, and also provides a new strategy to prepare highly active zero-valent iron for Cr(VI) removal.
摘要：
Developing efficient methods to degrade perfluorochemicals (PFCs), an emerging class of highly recalcitrant contaminants, are urgently needed in recent years, due to their persistence, high toxicity, and resistance to most regular treatment procedures. Here, a UV-photolysis system is reported for efficient mineralization of perfluorooctanoic acid (PFOA) via irradiation of ferric nitrate aqueous solution, where in-situ generating *NO2 and the effective Fe(3+)/Fe(2+) redox cycle synergistically play great roles on rapidly mediating the mineralization of PFOA. A fast PFOA removal kinetics with first-order kinetic constants of 2.262 h(-1) is observed at initial PFOA concentration of 5 ppm (50 mL volume), reaching approximately 92 % removal efficiency within only 0.5-h irradiation. Near-stoichiometric fluoride ions liberation and high total organic carbon (TOC) removal efficiency ( approximately 100 %) further validated the capability for completely destructive removal of PFOA. A tentative pathway for PFOA destruction is proposed. This work, by UV photolysis of abundant existing iron/nitrate-based systems in natural environment, provides an economical, sustainable and highly efficient approach for complete mineralization of perfluorinated chemicals.
通讯机构：
[Ai, ZH; Zhang, LZ] C;Cent China Normal Univ, Key Lab Pesticide & Chem Biol, Minist Educ, Inst Environm & Appl Chem, Wuhan 430079, Peoples R China.
关键词：
Photocatalytic NO removal;Oxygen vacancy;Dual-site activation;Air purification
摘要：
Photocatalytic technology provides an effective strategy for aerobic purification of dilute gaseous NO pollutant, but suffers from its low efficiency. In this study, we demonstrate that the bicomponent Au/CeO2 photocatalyst possesses an enhanced photocatalytic NO removal performance under visible light irradiation, with a higher NO conversion efficiency (65%) and triple rate constant (0.1451 min(-1)) versus CeO2 (50%, 0.0448 min(-1)). Density function theory calculations and experimental results revealed that oxygen vacancies on the CeO2 component could favorably initiate the adsorption and activation of O-2 to generate center dot O-2(-), simultaneously, Au nanoparticles loaded on the CeO2 surface were active centers for adsorption and activation of NO to produce NO+ by plasmonic holes of the Au under visible light irradiation. Subsequently, these center dot O-2(-) and NO+ species generated via dual-site activation pathway on Au/CeO2 photocatalyst reacted spontaneously to generate the final NO3-, leading to enhanced photocatalytic removal of NO. This study sheds light on a dual-site induced photocatalytic NO oxidation and advances the design of effective air purification photocatalyst.
摘要：
Organoarsenicals remediation requires degrading organoarsenicals and simultaneously immobilizing the resulted inorganic arsenic, and is thus a great challenge. In this study, a simulated solar light driven Fe(III)/Fe(II) cycle strategy was developed to degrade roxarsone and immobilize the generated inorganic arsenic via tuning the degree of Fe(III) hydrolysis. At pH values of 2.0 and 3.0, the hydrolysis of Fe(III) in the solution was suppressed to produce photoreactive Fe(III)-hydroxyl complexes, which could be excited by simulated solar light to generate (OH)-O-center dot for 85.3 % of roxarsone degradation into arsenate within 60 min. Density functional theory calculations suggested that Fe(OH)(H2O)(5)(2+ )with lower energy separation gap was the most photoactive Fe(III)hydroxyl complex for (OH)-O-center dot generation. With further increasing pH value to 6.0, the hydrolysis of Fe(III) was promoted to precipitate the arsenate for its immobilization, accompanying with the decrease of final iron ions and arsenate concentrations to 0.012 mmol L-1 and 58 mu g L-1, respectively. Meanwhile, the undegraded roxarsone was also adsorbed by the precipitate, increasing the overall roxarsone removal efficiency to 99.0 %. This study offers a promising strategy for the efficient organoarsenicals treatment, and also sheds light on the dual effects of iron based materials in organic pollutants degradation and heavy metal ions immobilization.
