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Low temperature surface oxygen activation in crystalline MnO_(2) triggered by lattice confined Pd single atoms

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Journal of Energy Chemistry 2021年第11期30卷 136-144,I0003页

作者： Xuemei Liao Yonghui Zhao Changwen Liu Xiaopeng Li Yu Sund Kenichi Kato Miho Yamauchi Zheng Jiang College of Food and Biological Engineering Xihua UniversityChengdu 610039SichuanChina CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute(SARI)Chinese Academy of Sciences(CAS)No.100Haike RoadPudong New DistrictShanghai 201210China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityNo.2999 North Renmin RoadSongjiang DistrictShanghai 201620China Institute for the Advancement of Higher Education Hokkaido UniversitySapporo 060-0817Japan Department of Chemistry Faculty of ScienceHokkaido UniversityN10W8Kita-kuSapporoHokkaido 060-0810Japan RIKEN SPring-8 Center1-1-1 KoutoSayo-choSayo-gunHyogo 679-5148Japan International Institute for Carbon-Neutral Energy Research(WPI-I2CNER) Kyushu UniversityMotooka 744Nishi-kuFukuoka 819-0395Japan Advanced Institute for Materials Research(AIMR) Tohoku University2-1-1 KatahiraAoba-kuSendai 980-8577Japan Shanghai Synchrotron Radiation Facility Zhangjiang LabShanghai Advanced Research Institute(SARI)Chinese Academy of Sciences(CAS)No.239 Zhangheng RoadPudong New DistrictShanghai 201203China Shanghai Institute of Applied Physics Chinese Academy of ScienceNo.2019 Jia Luo RoadJiading DistrictShanghai 201800China

Tuning the coordination environment is the research axis of single atom catalysts (SACs). SACs are commonly stabilized by various defects from support. Here, we report a lattice confined Pd SAC using MnO_(2) as support. Compared with the Pd clusters anchored on the surface, the lattice confined Pd single atoms allows spontaneous exaction of surrounding lattice oxygen at room temperature when employed in CO oxidation. The MnO_(2) supported Pd SAC exhibited a high turnover frequency of 0.203 s^(−1) at low reaction temperature, which is higher than that of recently reported Pd SACs. Theoretical calculations also confirmed the confined monatomic Pd activate lattice oxygen with an ultralow energy barrier. Our results illustrate that the unique coordination environment of single atom provided by lattice confinement is promising to boost the activity of SACs.

关键词： Single atom catalysts(SACs) Lattice confinement oxygen activation Manganese oxide nanofiber

Probing hydroxyl radical generation from H2O2 upon plasmon excitation of gold nanorods using electron spin resonance： Molecular oxygen-mediated activation

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Nano Research 2016年第6期9卷 1663-1673页

作者： Tao wen Hui Zhang Yu Chong Wayne G. Wamer Jun-Jie Yin Xiaochun Wu ing I O0190 China Division of Analytical Chemistry Office of Regulatory Science Center for Food Safety and Applied Nutrition US Food and Drug Administration College Park MD 20740 USA Institute of Basic Medical Sciences Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100005 China Division of Bioanalytical Chemistry Office of Regulatory Science Center for Food Safety and Applied Nutrition US Food and Drug Administration College Park MD 20740 USA

Gold nanostructures are among the noble metal nanomaterials being intensely studied due to their good biocompatibility, tunable localized surface plasmon resonance （SPR）, and ease of modification. These properties give gold nano- structures many potential chemical and biomedical applications. Herein, we demonstrate the critical role of oxygen activation during the decomposition of hydrogen peroxide （H202） in the presence of photoexcited gold nanorods （AuNRs） by using electron spin resonance （ESR） techniques. Upon SPR excitation, 02 is activated first, and the resulting reactive intermediates further activate H202 to produce ,OH. The reactive intermediates exhibit singlet oxygen-like （102-1ike） reactivity, indicated by 102-specific oxidation reaction, quenching behaviors, and the lack of the typical 102 ESR signal. In addition, by using the antioxidant sodium ascorbate （NaA） as an example, we show that hydroxyl radicals from H202 activation can induce much stronger NaA oxidation than that in the absence of H202. These results may have significant biomedical implications. For example, as oxidative stress levels are known to influence tumorigenesis and cancer progression, the ability to control redox status inside tumor microenvironments using noble metal nanostructures may provide new strategies for regulating the metabolism of reactive oxygen species and new approaches for cancer treatment.

关键词： gold nanorod oxygen activation hydroxyl radicalplasmon catalysis electron spin resonance

Unravelling the nature of the active species as well as the Mn doping effect over gamma-Al_(2)O_(3) catalyst for eliminating AsH_(3) and PH_(3)

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Journal of Environmental Sciences 2024年第2期136卷 213-225页

作者： Bowen Xu Jiaxin Qu Xueqian Wang Langlang Wang Yu Pu Ping Ning Yibing Xie Yixing Ma Qiang Ma Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China School of Architecture and Civil Engineering Chengdu UniversityChengdu 610106China

To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3)catalysts were *** characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component,increased the number of oxygen vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxygen,and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(TOF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).On the other hand,the introduction of Mn reduced the production of phosphate and As_(2)O_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverage and inerting of the active sites by phosphate and As_(2)O_(3),resulting in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal.

关键词： AsH_(3)-PH_(3)removal oxygen activation Mn doping Stability enhancement

Selective photocatalytic oxidation of methane to C1 oxygenates by regulating sizes and facets over Au/ZnO

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Nano Research 2024年第5期17卷 3810-3818页

作者： Qiang Zhou Xinyu Wang Xiaojie Tan Qinhua Zhang Hao Yang Tao Xing Mingqing Wang Mingbo Wu Wenting Wu State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical Engineering&Institute of New EnergyChina University of Petroleum(East China)Qingdao 266580China National Engineering Research Center of Coal Gasification and Coal-Based Advanced Materials ShanDong Energy Group CO.LTDJinan 250101China

Photocatalytic oxidation of methane to value-added chemicals is a promising process under mild conditions,nevertheless confronting great challenges in efficiently activating C-H bonds and inhibiting ***,we propose a comprehensive strategy for the selective generation of reactive oxygen species(ROS)by regulating the sizes and facets of Au nanoparticles loaded on *** photocatalytic methane oxidation at ambient temperature,a high oxygenates yield of 36.4 mmol·g^(-1)·h^(-1) with a nearly 100%selectivity has been achieved over the optimized 1.0%Au/ZnO-9.6(1%Au with(111)facet and 9.6 nm size on ZnO)photocatalyst,exceeding most reported *** investigations reveal that 1.0%Au/ZnO-9.6 with the medium size and Au(111)facet guarantees the favourable formation of superoxide radicals(·OOH)through mild oxygen reduction,ultimately leading to excellent photocatalytic methane oxidation *** work provides some guidance for the delicate design of photocatalysts for efficient photocatalytic methane oxidation and oxygen utilization.

关键词： photocatalysis methane oxidation radical regulation oxygen activation nanomaterial

oxygen Molecule activation on Single-Atom Catalysts with Cu, Ag, and Au: A Cluster Model Study

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Journal of Materials Science and Chemical Engineering 2021年第4期9卷 46-59页

作者： Yangliu Wu Xunlei Ding Wei Li Joseph Israel Gurti School of Mathematics and Physics North China Electric Power University Beijing China Institute of Clusters and Low Dimensional Nanomaterials North China Electric Power University Beijing China

(M = Au, Ag, Cu;n= 1, 2, 3) clusters were used as a cluster model to study the activation of oxygen molecules on single-atom catalysts. Structures of clusters were studied by density functional calculations with global optimization. For each n, the most stable structures are quite similar for different metal types, and the oxygen molecule prefers to be adsorbed onto M atoms. It is found that the activation degree of oxygen is higher on clusters with non-noble metal Cu than that of Ag or Au containing clusters, by comparing the changes of O-O bond length and vibrational frequency, natural charge population analysis, Fuzzy bond order analysis, and energy barriers of O2 dissociation. CO oxidation was used as a probe reaction to study the reactivity of Cu-containing clusters, and it is found that the reactivity decreases with the increase of the size of silicon-oxygen clusters. Our results give a new aspect to understand the reaction mechanism of non-precious metal single-atom catalyst for oxygen activation with high efficiency.

关键词： oxygen activation Single-Atom Catalysis Non-Noble Metals Density Func-tion Theory Micro-Mechanism

Sustainable micro-activation of dissolved oxygen driving pollutant conversion on Mo-enhanced zinc sulfide surface in natural conditions

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Fundamental Research 2023年第3期3卷 422-429页

作者： Chao Lu Qian Fang Chun Hu Lai Lyu Key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of EducationInstitute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou 510006China Institute of Rural Revitalization Guangzhou UniversityGuangzhou 510006China

The activation of inert oxygen(O_(2))often consumes enormous amounts of energy and resources,which is a global challenge in the field of environmental remediation and fuel *** pollutants are abundant in electrons and are promising alternative electron ***,we implement sustainable microactivation of dissolved oxygen(DO)by using the electrons and adsorption energy of pollutants by creating a nonequilibrium microsurface on nanoparticle-integrated molybdenum(Mo)lattice-doped zinc sulfide(ZnS)composites(MZS-1).Organic pollutants were quickly removed by DO microactivation in the MZS-1 system under natural conditions without any additional energy or electron *** turnover frequency(TOF,per Mo atom basis)is 5 orders of magnitude higher than those of homogeneous *** and electronic characterization technologies reveal the change in the crystalline phase(Zn-S-Mo)and the activation of π-electrons on six-membered rings of ZnS after Mo doping,which results in the formation of a nonequilibrium microsurface on *** is the key for the strong interfacial interaction and directional electron transfer from pollutants to MZS-1 through the delocalized π-π conjugation effect and from MZS-1 to DO via Zn-S-Mo,as demonstrated by electron paramagnetic resonance(EPR)techniques and density functional theory(DFT)*** process achieves the efficient use of pollutants and the low-energy activation of O_(2) through the construction of a nonequilibrium microsurface,which shows new significance for water treatment.

关键词： Wastewater treatment Microelectric field surface construction Fenton-like reaction oxygen activation Pollutant electron donation

Degradation of organic contaminants through the activation of oxygen using zero valent copper coupled with sodium tripolyphosphate under neutral conditions

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Journal of Environmental Sciences 2020年第4期32卷 375-384页

作者： Chengwu Zhang Lishuang Xuan Jingyi Zhang Fang Yuan Xianglong Kong Chuanyu Qin Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun 130021China Jilin Provincial Key Laboratory of Water Resources and Environment Jilin UniversityChangchun 130021China National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology Jilin UniversityChangchun 130021China

In this study,sodium tripolyphosphate(STPP)was used to promote the removal of organic pollutants in a zero-valent copper(ZVC)/O2 system under neutral conditions for the first time.20 mg/L p-nitrophenol(PNP)can be completely decomposed within 120 min in the ZVC/O2/STPP *** PNP degradation process followed pseudo-first-order kinetics and the degradation rate of PNP gradually increased upon the decreasing ZVC particle *** optimal pH of the reaction system was *** mechanism investigation showed that Cu+generated by ZVC corrosion was the main reducing agent for the activation of 02 to produce ROS.-OH was identified as the only ROS formed during the degradation of PNP and its production pathway was the double-electron activation of O2(O2→H2 O2→·OH).In this process,STPP did not only promote the release of Cu+through its complexation,but also promoted the production of OH by reducing the redox potential of Cu2+/Cu+.In addition,we could initiate and terminate the reaction by controlling the *** pH8.1,the reaction was *** was recycled to continuously promote the corrosion of ZVC and O2 activation as long as the pH wasactivation and organic contaminants removal.

关键词： Sodium tripolyphosphate Zero valent copper corrosion oxygen activation pH control

In situ Synthesis of Ultrasmall Au Clusters on Thiol-modified CeO_(2) with Enhanced Stability and CO Oxidation Activity

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Chemical Research in Chinese Universities 2023年第6期39卷 921-927页

作者： LI Lingling XU Jinhui LIANG Xi WU Xueting WANG Xiao SONG Shuyan ZHANG Hongjie State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026P.R.China Department of Chemistry Tsinghua UniversityBeijing 100084P.R.

Gold(Au)nanoclusters supported on various supports have been widely used in the fields of energy and ***,the poor thermal stability of Au nanoclusters on the support interface usually leads to a reduction or even loss of catalytic ***,we used an in situ reduction method to synthesize Au nanoclusters on ceria(CeO_(2))*** this method,sulfhydryl groups were used to modify CeO_(2) nanospheres first,and then Au clusters with an average diameter of 1.5 nm were grown on the surface of ceria reduced with sodium *** presence of the Au-S-Ce structure enhances the electron transfer efficiency,making the material exhibit high CO oxidation activity at room ***,due to the strong binding energy of S and Au,the material exhibits a high stability for long time running *** strategy provides an idea for designing stable and active supported ultrasmall Au nanoclusters catalytic materials.

关键词： Au cluster Sulfhydryl oxygen activation In situ synthesis

Elemental Doping Boosts Charge-Transfer Excitonic States in Polymeric Photocatalysts for Selective Oxidation Reaction

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Precision Chemistry 2023年第1期1卷 40-48页

作者： Peng Zhang Lei Li Jun Zhao Hui Wang Xiaodong Zhang Yi Xie Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Institute of Energy Hefei Comprehensive National Science CenterHefeiAnhui 230031China

Energy-transfer-mediated synthetic reactions play vital roles in the production of high-value-added organics,where the longlived exciton harvesting is an essential precondition for the ***,for semiconductors with strong excitonic effects like conjugated polymers,their predominant Frenkel exciton with a short lifetime in the unified framework gives rise to low efficiency ***,we propose the boosting of the charge-transfer exciton with a long-lived state by introducing spatially separated electron and hole *** taking polymeric carbon nitride(PCN)as a prototype,we demonstrate that sulfur doping leads to the formation of electron donor and acceptor motifs in the tri-s-triazinebased backbone,which would accommodate long-lived excitonic states with remarkable charge-transfer *** extraordinary long-lived charge-transfer exciton harvesting endows sulfur-doped PCN with high-efficiency photocatalytic performance in 1O2 generation and selective oxidation of organic *** work provides a brand new perspective for designing advanced photocatalysts for energy-transfer-mediated sunlight utilization.

关键词： Charge-transfer state Electron donor−acceptor Elemental doping oxygen activation Energy transfer