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Electrocatalytic and photocatalytic performance of noble metal doped monolayer MoS2 in the hydrogen evolution reaction: A first principles study 被引量:4
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作者 Zheng Zhang Kai Chen +2 位作者 Qiang Zhao Mei Huang Xiaoping Ouyang 《Nano Materials Science》 CAS CSCD 2021年第1期89-94,共6页
To maximize the catalytic performance of MoS_(2) in the hydrogen evolution reaction,we investigate the electrocatalytic and photocatalytic performance of monolayer MoS_(2) doped with noble metal(Ag,Au,Cu,Pd,and Pt)usi... To maximize the catalytic performance of MoS_(2) in the hydrogen evolution reaction,we investigate the electrocatalytic and photocatalytic performance of monolayer MoS_(2) doped with noble metal(Ag,Au,Cu,Pd,and Pt)using first principles calculation combined with the climbing image nudged elastic band method.We find the band gap of the monolayer MoS_(2) is reduced significantly by the noble metal doping,which is unfavorable to improving its photocatalytic performance.The optical absorption coefficient shows that the doping does not increase the ability of the monolayer MoS_(2) to absorb visible light.The monolayer MoS_(2) doped with the noble metal is not a potential photocatalyst for the hydrogen evolution reaction because the band edge position of the conduction band minimum is lower than-4.44 eV,the reduction potential of H^(+)/H_(2).Fortunately,the band gap reduction increases the electron transport performance of the monolayer MoS_(2),and the activation energy of water splitting is greatly reduced by the noble metal doping,especially the Pt doping.On the whole,noble metal doping can enhance the electrocatalytic performance of the monolayer MoS_(2). 展开更多
关键词 ELECTROCATALYTIC Monolayer MoS2 Noble metal doping Hydrogen evolution reaction First principles calculation
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Low Temperature H_(2) Production from Formic Acid Aqueous Solution Catalyzed on Metal Doped Mo_(2)C
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作者 Shuaishuai Zhu Zhigang Pan +1 位作者 Yaqiu Tao Yue Chen 《Journal of Renewable Materials》 SCIE EI 2020年第8期939-946,共8页
Hydrogen is recognized as a promising energy scours in the close future.Online hydrogen preparation from formic acid under mild reaction conditions causes extensive interests.Mo_(2)C and metal(Fe,Ni,Co,K)doped Mo_(2)C... Hydrogen is recognized as a promising energy scours in the close future.Online hydrogen preparation from formic acid under mild reaction conditions causes extensive interests.Mo_(2)C and metal(Fe,Ni,Co,K)doped Mo_(2)C on granular activated carbon(GAC)were prepared and used as heterogeneous catalysts for H2 generation from formic acid on a fixed bed reactor at 100–250°C.The formic acid conversions on doped Mo_(2)C-Me/GAC are clearly improved,especially at lower reaction temperatures.Co doping presents outstanding effect on H2 selectivity and conversion rate compared to Ni and Fe.A 56.3%formic acid conversion was reached on Mo_(2)C-Co/GAC at 100°C,which triples that on Mo_(2)C/GAC at the same temperature.At 150°C,a high formic acid conversion over 90%was reached on Mo_(2)C-Co/GAC.These long lifetime catalysts with no precious metal provide a low cost route to hydrogen production from formic acid. 展开更多
关键词 Hydrogen production energy storage and conversion Mo_(2)C/GAC metal doping formic acid decomposition carbon materials
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Enhancing hydrogen evolution reaction performance of transition metal doped two-dimensional electride Ca_(2)N
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作者 Baoyu Liu Ziqiang Chen +5 位作者 Rui Xiong Xuhui Yang Yinggan Zhang Teng Xie Cuilian Wen Baisheng Sa 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第6期487-491,共5页
Two-dimensional electride Ca_(2)N has strong electron transfer ability and low work function,which is a potential candidate for hydrogen evolution reaction(HER)catalyst.In this work,based on density functional theory ... Two-dimensional electride Ca_(2)N has strong electron transfer ability and low work function,which is a potential candidate for hydrogen evolution reaction(HER)catalyst.In this work,based on density functional theory calculations,we adopt two strategies to improve the HER catalytic activity of Ca_(2)N monolayer:introducing Ca or N vacancy and doping transition metal atoms(TM,refers to Ti,V,Cr,Mn,Fe,Zr,Nb,Mo,Ru,Hf,Ta and W).Interestingly,the Gibbs free energyΔG_(H*)of Ca_(2)N monolayer after introducing N vacancy is reduced to-0.146 e V,showing good HER catalytic activity.It is highlighted that,the HER catalytic activity of Ca_(2)N monolayer can be further enhanced with TM doping,the Gibbs free energyΔG_(H*)of single Mo and double Mn doped Ca_(2)N are predicted to be 0.119 and 0.139 e V,respectively.The present results will provide good theoretical guidance for the HER catalysis applications of two-dimensional electride Ca_(2)N monolayer. 展开更多
关键词 Two-dimensional electride Ca_(2)N Density functional theory calculations Hydrogen evolution reaction Transition metal doping
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A comparison study of alkali metal-doped g-C_3N_4 for visible-light photocatalytic hydrogen evolution 被引量:25
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作者 Jing Jiang Shaowen Cao +1 位作者 Chenglong Hu Chunhua Chen 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第12期1981-1989,共9页
Photocatalytic hydrogen production based on semiconductor photocatalysts has been considered as one of the most promising strategies to resolve the global energy shortage.Graphitic carbon nitride(g‐C3N4)has been a st... Photocatalytic hydrogen production based on semiconductor photocatalysts has been considered as one of the most promising strategies to resolve the global energy shortage.Graphitic carbon nitride(g‐C3N4)has been a star visible‐light photocatalyst in this field due to its various advantages.However,pristine g‐C3N4usually exhibits limited activity.Herein,to enhance the performance of g‐C3N4,alkali metal ion(Li+,Na+,or K+)‐doped g‐C3N4are prepared via facile high‐temperature treatment.The prepared samples are characterized and analyzed using the technique of XRD,ICP‐AES,SEM,UV‐vis DRS,BET,XPS,PL,TRPL,photoelectrochemical measurements,photocatalytic tests,etc.The resultant doped photocatalysts show enhanced visible‐light photocatalytic activities for hydrogen production,benefiting from the increased specific surface areas(which provide more active sites),decreased band gaps for extended visible‐light absorption,and improved electronic structures for efficient charge transfer.In particular,because of the optimal tuning of both microstructure and electronic structure,the Na‐doped g‐C3N4shows the most effective utilization of photogenerated electrons during the water reduction process.As a result,the highest photocatalytic performance is achieved over the Na‐doped g‐C3N4photocatalyst(18.7?mol/h),3.7times that of pristine g‐C3N4(5.0?mol/h).This work gives a systematic study for the understanding of doping effect of alkali metals in semiconductor photocatalysis. 展开更多
关键词 g‐C3N4 Alkali metal doping Photocatalytic hydrogen production Visible light Charge transfer
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A Fundamental DFT Study of Anatase(TiO2) Doped with 3d Transition Metals for High Photocatalytic Activities 被引量:2
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作者 刘晓烨 李育彪 +1 位作者 WEI Zhenlun SHI Ling 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第2期403-408,共6页
Anatase(TiO_2) has been widely used in photocatalysis. However, it can only absorb near-ultraviolet light with a wavelength below approximately 388 nm due to a wide band gap. Therefore a modification should be made ... Anatase(TiO_2) has been widely used in photocatalysis. However, it can only absorb near-ultraviolet light with a wavelength below approximately 388 nm due to a wide band gap. Therefore a modification should be made for anatase to increase its capability in utilizing more abundant visible light. We investigated the doped anatase with the most promising 3d transition metal elements, and the results showed that the visible light absorption intensity was increased significantly due to the reduced band gap and the cavitation effects. As compared to other 3d transition metals, Cu was found to be the most effective one in improving anatase photocatalytic effects. In addition, greater Cu concentration doped in the anatase increased the photocatalysis effects but reduced the anatase stability, therefore, an optimized Cu concentration should be considered to optimize the anatase photocatalysis activity. 展开更多
关键词 anatase doping transition metal elements DFT
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Elucidating structure-performance correlations in gas-phase selective ethanol oxidation and CO oxidation over metal-dopedγ-MnO2
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作者 Panpan Wang Jiahao Duan +2 位作者 Jie Wang Fuming Mei Peng Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第8期1298-1310,共13页
Despite of considerable efforts on the MnO2-based catalytic combustion,the different structural and component requirements of MnO2 for gas-phase selective oxidation and complete oxidation largely remain unknown.By com... Despite of considerable efforts on the MnO2-based catalytic combustion,the different structural and component requirements of MnO2 for gas-phase selective oxidation and complete oxidation largely remain unknown.By comparing four types of MnO2 with different crystal structures(α,β,γandδ),γ-MnO2 was found to be the most efficient catalyst for both aerobic selective oxidation of ethanol and CO oxidation.The structural effect ofγ-MnO2 was further investigated by doping metal ions into the framework and by comparing the catalytic performance in the gas-phase aerobic oxidation of CO and ethanol.Among ten M-γ-MnO2 catalysts,Zn-γ-MnO2 showed the lowest temperature(160°C)for achieving 90%CO conversion.The CO oxidation activity of the M-γ-MnO2 catalysts was found to be more relevant to the surface acidity-basicity than the reducibility.In contrast,surface reducibility has been demonstrated to be more crucial in the gas-phase ethanol oxidation.Cu-γ-MnO2 with higher reducibility and more oxygen vacancies of Mn^2+/Mn^3+species exhibited higher catalytic activity in the selective ethanol oxidation.Cu-γ-MnO2 achieved the highest acetaldehyde yield(75%)and space-time-yield(5.4 g gcat^-1 h^-1)at 200°C,which are even comparable to the results obtained by the state-of-the-art silver and gold-containing catalysts.Characterization results and kinetic studies further suggest that the CO oxidation follows the lattice oxygen-based Mars-van Krevelen mechanism,whereas both surface lattice oxygen and adsorbed oxygen species involve in the ethanol activation. 展开更多
关键词 MNO2 metal doping Ethanol oxidation ACETALDEHYDE Catalytic CO oxidation
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Effect of Doped Alkali Metal Ions on the SO_(2) Capture Performance of MnO_(2) Desulfurization Materials at Low Temperature
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作者 Xing Li Yugo Osaka +2 位作者 Hongyu Huang Takuya Tsujiguchi Akio Kodama 《Journal of Renewable Materials》 SCIE EI 2021年第9期1541-1553,共13页
Sulfur dioxide(SO_(2))emissions from diesel exhaust pose a serious threat to the environment and human health.Thus,desulfurization technology and the performance of desulfurization materials must be improved.In this s... Sulfur dioxide(SO_(2))emissions from diesel exhaust pose a serious threat to the environment and human health.Thus,desulfurization technology and the performance of desulfurization materials must be improved.In this study,MnO_(2) was modified with various alkali metal ions using the impregnation method to enhance its SO_(2) capture performance.The composites were characterized intensively by scanning electron microscopy,energydispersive X-ray spectroscopy,X-ray diffraction spectroscopy,and Brunauer-Emmett-Teller theory.The SO_(2) capture performance of these composites were measured via thermogravimetry,and the effect of doping with alkali metal ions on the SO_(2) capture performance of MnO_(2) was investigated.Results showed that the SO_(2) capture performance of MnO_(2) could be enhanced by doping with alkali metal ions,and the MnO_(2) composite doped with LiOH(2.0 mol/L)had the best SO_(2) capture capacity(124 mgSO_(2)/gMaterial),which was 18%higher than that of pure MnO_(2).Moreover,the type and concentration of alkali metal ions had varying effects on the SO_(2) capture performance of MnO_(2).In our experiment,the SO_(2) capture performance of the MnO_(2) doped with NaOH,LiCl,Na2CO3,K2CO3,and Li2CO3 composites were worse than that of pure MnO_(2).Therefore,the influences of the type and concentration of alkali metal ions to be doped into desulfurization materials must be considered comprehensively. 展开更多
关键词 Sulfur dioxide capture desulfurization materials manganese dioxide alkali metal ions doped
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Influence of alkali metal doping on surface properties and catalytic activity/selectivity of CaO catalysts in oxidative coupling of methane 被引量:5
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作者 V.H.Rane S.T.Chaudhari V.R.Choudhary 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第4期313-320,共8页
Surface properties (viz. surface area, basicity/base strength distribution, and crystal phases) of alkali metal doped CaO (alkali metal/Ca= 0.1 and 0.4) catalysts and their catalytic activity/selectivity in oxidat... Surface properties (viz. surface area, basicity/base strength distribution, and crystal phases) of alkali metal doped CaO (alkali metal/Ca= 0.1 and 0.4) catalysts and their catalytic activity/selectivity in oxidative coupling of methane (OCM) to higher hydrocarbons at different reaction conditions (viz. temperature, 700 and 750 ℃; CH4/O2 ratio, 4.0 and 8.0 and space velocity, 5140-20550 cm^3 ·g^-1·h^-1) have been investigated. The influence of catalyst calcination temperature on the activity/selectivity has also been investigated. The surface properties (viz. surface area, basicity/base strength distribution) and catalytic activity/selectivity of the alkali metal doped CaO catalysts are strongly influenced by the alkali metal promoter and its concentration in the alkali metal doped CaO catalysts. An addition of alkali metal promoter to CaO results in a large decrease in the surface area but a large increase in the surface basicity (strong basic sites) and the C2+ selectivity and yield of the catalysts in the OCM process. The activity and selectivity are strongly influenced by the catalyst calcination temperature. No direct relationship between surface basicity and catalytic activity/selectivity has been observed. Among the alkali metal doped CaO catalysts, Na-CaO (Na/Ca = 0.1, before calcination) catalyst (calcined at 750 ℃), showed best performance (C2+ selectivity of 68.8% with 24.7% methane conversion), whereas the poorest performance was shown by the Rb-CaO catalyst in the OCM process. 展开更多
关键词 oxidative coupling of methane alkali metal doped CaO catalysts basicity/base strength distribution catalytic activity/selectivity
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Progress in doping and crystal deformation for polyanions cathode based lithium-ion batteries
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作者 Sajeela Awasthi Srikanta Moharana +6 位作者 Vaneet Kumar Nannan Wang Elham Chmanehpour Anupam Deep Sharma Santosh K.Tiwari Vijay Kumar Yogendra Kumar Mishra 《Nano Materials Science》 EI CAS CSCD 2024年第5期504-535,共32页
Polyanion-based materials are considered one of the most attractive and promising cathode materials for lithiumion batteries(LIBs)due to their good stability,safety,cost-effectiveness,suitable voltages,and minimal env... Polyanion-based materials are considered one of the most attractive and promising cathode materials for lithiumion batteries(LIBs)due to their good stability,safety,cost-effectiveness,suitable voltages,and minimal environmental impact.However,these materials suffer from poor rate capability and low-temperature performance owing to limited electronic and ionic conductivity,which restricts their practical applicability.Recent developments,such as coating material particles with carbon or a conductive polymer,crystal deformation through the doping of foreign metal ions,and the production of nanostructured materials,have significantly enhanced the electrochemical performances of these materials.The successful applications of polyanion-based materials,especially in lithium-ion batteries,have been extensively reported.This comprehensive review discusses the current progress in crystal deformation in polyanion-based cathode materials,including phosphates,fluorophosphates,pyrophosphates,borates,silicates,sulfates,fluorosilicates,and oxalates.Therefore,this review provides detailed discussions on their synthesis strategies,electrochemical performance,and the doping of various ions. 展开更多
关键词 Crystal deformation in polyanions metal ions doping Cathode materials Surface modification Lithium-ion batteries
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Single atom doping induced charge-specific distribution of Cu1-TiO_(2) for selective aniline oxidation via a new mechanism
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作者 Jiaheng Qin Wantong Zhao +6 位作者 Jie Song Nan Luo Zheng-Lan Ma Baojun Wang Jiantai Ma Riguang Zhang Yu Long 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期98-111,共14页
Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile... Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile,identifying the active site also represents a significant obstacle,primarily due to the intricate electronic environment of single atom site doped metal oxide.Herein,a single atom Cu doped TiO_(2)catalyst(Cu_(1)-TiO_(2)) is prepared via a simple“colloid-acid treatment”strategy,which switches aniline oxidation selectivity of TiO_(2) from azoxybenzene to nitrosobenzene,without using additives or changing solvent,while other metal or nonmetal doped TiO_(2) did not possess.Comprehensive mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate,two PhNOH condense to azoxybenzene over TiO_(2) catalyst.As for Cu_(1)-TiO_(2),the charge-specific distribution between the isolated Cu and TiO_(2) generates unique Cu_(1)-O-Ti hybridization structure with nine catalytic active sites,eight of them make PhNOH take place spontaneous dissociation to produce nitrosobenzene.This work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites. 展开更多
关键词 Single atom doped metal oxide Aniline oxidation Selectivity New mechanism Active site
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Tailoring local structures of atomically dispersed copper sites for highly selective CO_(2) electroreduction
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作者 Kyung‐Jong Noh Byoung Joon Park +5 位作者 Ying Wang Yejung Choi Sang‐Hoon You Yong‐Tae Kim Kug‐Seung Lee Jeong Woo Han 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期79-90,共12页
Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construc... Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains challenging.Here,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal precursor.Edge‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus RHE.Computational studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH binding.This research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions. 展开更多
关键词 atomic local structure density functional theory electrochemical CO_(2)reduction metal nitrogen‐doped carbon single‐atom catalyst
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Doping-induced metal–N active sites and bandgap engineering in graphitic carbon nitride for enhancing photocatalytic H_(2 )evolution performance 被引量:6
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作者 Xiaohui Yu Haiwei Su +3 位作者 Jianping Zou Qinqin Liu Lele Wang Hua Tang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期421-432,共12页
Durable and inexpensive graphitic carbon nitride(g-C_(3)N_(4))demonstrates great potential for achieving efficient photocatalytic hydrogen evolution reduction(HER).To further improve its activity,g-C_(3)N_(4)was subje... Durable and inexpensive graphitic carbon nitride(g-C_(3)N_(4))demonstrates great potential for achieving efficient photocatalytic hydrogen evolution reduction(HER).To further improve its activity,g-C_(3)N_(4)was subjected to atomic-level structural engineering by doping with transition metals(M=Fe,Co,or Ni),which simultaneously induced the formation of metal-N active sites in the g-C_(3)N_(4)framework and modulated the bandgap of g-C_(3)N_(4).Experiments and density functional theory calculations further verified that the as-formed metal-N bonds in M-doped g-C_(3)N_(4)acted as an"electron transfer bridge",where the migration of photo-generated electrons along the bridge enhanced the efficiency of separation of the photogenerated charges,and the optimized bandgap of g-C_(3)N_(4)afforded stronger reduction ability and wider light absorption.As a result,doping with either Fe,Co,or Ni had a positive effect on the HER activity,where Co-doped g-C_(3)N_(4)exhibited the highest performance.The findings illustrate that this atomic-level structural engineering could efficiently improve the HER activity and inspire the design of powerful photocatalysts. 展开更多
关键词 g-C_(3)N_(4) Photocatalytic H_(2)generation metal-N active sites Transition metal doping Band gap engineering
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Alkali metal cation doping of metal-organic framework for enhancing carbon dioxide adsorption capacity 被引量:6
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作者 Yan Cao Yunxia Zhao +1 位作者 Fujiao Song Qin Zhong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第4期468-474,共7页
Metal-organic frameworks (MOFs) have attracted much attention as adsorbents for the separation of CO2 from flue gas or natural gas. Here, a typical metal-organic framework HKUST-I(also named Cu-BTC or MOF-199) was... Metal-organic frameworks (MOFs) have attracted much attention as adsorbents for the separation of CO2 from flue gas or natural gas. Here, a typical metal-organic framework HKUST-I(also named Cu-BTC or MOF-199) was chemically reduced by doping it with alkali metals (Li, Na and K) and they were further used to investigate their CO2 adsorption capacities. The structural information, surface chemistry and thermal behavior of the prepared adsorbent samples were characterized by X-ray powder diffraction (XRD), thermo-gravimetric analysis (TGA) and nitrogen adsorption-desorption isotherm analysis. The results showed that the CO2 storage capacity of HKUST-1 doped with moderate quantities of Li+, Na+ and K+, individually, was greater than that of unmodified HKUST-1. The highest CO2 adsorption uptake of 8.64 mmol/g was obtained with 1K-HKUST-1, and it was ca. 11% increase in adsorption capacity at 298 K and 18 bar as compared with HKUST- 1. Moreover, adsorption tests showed that HKUST-1 and 1K-HKUST-1 displayed much higher adsorption capacities of CO2 than those of N2. Finally, the adsorption/desorption cycle experiment revealed that the adsorption performance of 1K-HKUST-1 was fairly stable, without obvious deterioration in the adsorption capacity of CO2 after 10 cycles. 展开更多
关键词 metal-organic framework HKUST-1 carbon dioxide adsorption alkali metals cation doping adsorption-desorption cycles
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Confined synthesis of MoS_(2) with rich co-doped edges for enhanced hydrogen evolution performance 被引量:3
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作者 Zongge Li Chenlei Li +5 位作者 Jianwen Chen Xu Xing Yaqun Wang Ying Zhang Miaosen Yang Guoxin Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期18-26,I0002,共10页
Activating MoS_(2) with atomic metal doping is promising to harvest desirable Pt-matched hydrogen evolution reaction(HER)catalytic performance.Herein,we developed an efficient method to access edgerich lattice-distort... Activating MoS_(2) with atomic metal doping is promising to harvest desirable Pt-matched hydrogen evolution reaction(HER)catalytic performance.Herein,we developed an efficient method to access edgerich lattice-distorted MoS_(2) for highly efficient HER via in-situ sulphuration of atomic Co/Mo species that were well-dispersed in a formamide-derived N-doped carbonaceous(f-NC)substrate.Apart from others,pre-embedding Co/Mo species in f-NC controls the release of metal sources upon annealing in S vapor,grafting the as-made MoS_(2) with merits of short-range crystallinity,distorted lattices,rich defects,and more edges exposed.The content of atomic Co species embedded in MoS_(2) reaches up to 2.85 at.%,and its atomic dispersion has been systematically confirmed by using XRD,HRTEM,XPS,and XAS characterizations.The Co-doped MoS_(2) sample exhibits excellent HER activity,achieving overpotentials of 67 and155 m V at j=10 m A cm^(-2) in 1.0 M KOH and 0.5 M H_(2)SO_(4),respectively.Density functional theory simulations suggest that,compared with free-doping MoS_(2),the edged Co doping is responsible for the significantly improved HER activity.Our method,in addition to providing reliable Pt-matched HER catalysts,may also inspire the general synthesis of edge-rich metal-doped metal chalcogenide for a wide range of energy conversion applications. 展开更多
关键词 Molybdenum sulfide metal doping FORMAMIDE Carbon material Hydrogen evolution reaction
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Promoted CO2 electroreduction over indium-doped SnP3: A computational study 被引量:2
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作者 Yuefeng Zhang Wenchao Zhang +1 位作者 Yuezhan Feng Jianmin Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第9期1-6,I0001,共7页
It is generally considered that the hydrogenation of CO2 is the critical bottleneck of the CO2 electroreduction.In this work,with the aid of density functional theory(DFT)calculations,the catalytic hydrogenation of CO... It is generally considered that the hydrogenation of CO2 is the critical bottleneck of the CO2 electroreduction.In this work,with the aid of density functional theory(DFT)calculations,the catalytic hydrogenation of CO2 molecules over Indium-doped SnP3 catalyst were systematically studied.Through doping with indium(In)atom,the energy barrier of CO2 protonation is reduced and OCHO*species could easily be generated.This is mainly due to the p orbital of In exhibits strong hybridization with the p orbital of O,indicating that there is a strong interaction between OCHO*and In-doped SnP3 catalyst.As a result,In-doped SnP3 possesses high-efficiency and high-selectivity for converting CO2 into HCOOH with a low limiting potential of-0.17 V.Our findings will offer theoretical guidance to CO2 electroreduction. 展开更多
关键词 CO2 electroreduction SnP3 Indium metal doping Formic acid First principles
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Doping effects of transition metals on the superconductivity of (Li,Fe)OHFeSe films 被引量:1
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作者 Dong Li Peipei Shen +7 位作者 Sheng Ma Zhongxu Wei Jie Yuan Kui Jin Li Yu Fang Zhou Xiaoli Dong Zhongxian Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第1期104-108,共5页
The doping effects of transition metals(TMs = Mn, Co, Ni, and Cu) on the superconducting critical parameters are investigated in the films of iron selenide(Li,Fe)OHFe Se. The samples are grown via a matrix-assisted hy... The doping effects of transition metals(TMs = Mn, Co, Ni, and Cu) on the superconducting critical parameters are investigated in the films of iron selenide(Li,Fe)OHFe Se. The samples are grown via a matrix-assisted hydrothermal epitaxy method. Among the TMs, the elements of Mn and Co adjacent to Fe are observed to be incorporated into the crystal lattice more easily. It is suggested that the doped TMs mainly occupy the iron sites of the intercalated(Li,Fe)OH layers rather than those of the superconducting Fe Se layers. We find that the critical current density J_(c) can be enhanced much more strongly by the Mn dopant than the other TMs, while the critical temperature T_(c) is weakly affected by the TM doping. 展开更多
关键词 iron-based superconductivity transition metals doping critical current density
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Synergistic Effect of Metal Doping and Tethered Ligand Promoted High-Selectivity Conversion of CO_(2)to C_(2)Oxygenates at Ultra-Low Potential 被引量:1
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作者 Xiaowan Bai Li Shi +4 位作者 Qiang Li Chongyi Ling Yixin Ouyang Shiyan Wang Jinlan Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2022年第3期892-898,共7页
Effectively controlling the selectivity of C_(2) oxygenates is desirable for electrocatalytic CO_(2) reduction.Copper catalyst has been considered as the most potential for reducing CO_(2) to C_(2) products,but it sti... Effectively controlling the selectivity of C_(2) oxygenates is desirable for electrocatalytic CO_(2) reduction.Copper catalyst has been considered as the most potential for reducing CO_(2) to C_(2) products,but it still suffers from low C_(2) selectivity,high overpotential,and competitive hydrogen evolution reaction(HER).Here,we propose a design strategy to introduce a second metal that weakly binds to H and a functional ligand that provides hydrogen bonds and protons to achieve high selectivity of C_(2)oxygenates and effective suppression of HER on the Cu(100)surface simultaneously.Seven metals and eleven ligands are screened using first-principles calculations,which shows that Sn is the most efficient for inhibiting HER and cysteamine(CYS)ligand is the most significant in reducing the limiting potential of^(*)CO hydrogenation to^(*)CHO.In the post C-C coupling steps,a so-called“pulling effect”that transfers H in the CYS ligand as a viable proton donor to the C_(2)intermediate to form an H bond,can further stabilize the OH group and facilitate the selection of C_(2)products toward oxygenates.Therefore,this heterogeneous electrocatalyst can effectively reduce CO_(2)to ethanol and ethylene glycol with an ultra-low limiting potential of-0.43 V.This study provides a new strategy for effectively improving the selectivity of C_(2)oxygenates and inhibiting HER to achieve advanced electrocatalytic CO_(2)reduction. 展开更多
关键词 metal doping hydrogen-bonding ligand density functional theory electrochemical CO_(2)reduction C_(2)oxygenates selectivity
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Transition metal-nitrogen sites for electrochemical carbon dioxide reduction reaction 被引量:4
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作者 Chengcheng Yan Long Lin +1 位作者 Guoxiong Wang Xinhe Bao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第1期23-37,共15页
Electrochemical CO2 reduction reaction(CO2RR)powered by renewable electricity has emerged as the most promising technique for CO2 conversion,making it possible to realize a carbon‐neutral cycle.Highly efficient,robus... Electrochemical CO2 reduction reaction(CO2RR)powered by renewable electricity has emerged as the most promising technique for CO2 conversion,making it possible to realize a carbon‐neutral cycle.Highly efficient,robust,and cost‐effective catalysts are highly demanded for the near‐future practical applications of CO2RR.Previous studies on atomically dispersed metal‐nitrogen(M‐Nx)sites constituted of earth abundant elements with maximum atom‐utilization efficiency have demonstrated their performance towards CO2RR.This review summarizes recent advances on a variety of M‐Nx sites‐containing transition metal‐centered macrocyclic complexes,metal organic frameworks,and M‐Nx‐doped carbon materials for efficient CO2RR,including both experimental and theoretical studies.The roles of metal centers,coordinated ligands,and conductive supports on the intrinsic activity and selectivity,together with the importance of reaction conditions for improved performance are discussed.The mechanisms of CO2RR over these M‐Nx‐containing materials are presented to provide useful guidance for the rational design of efficient catalysts towards CO2RR. 展开更多
关键词 Electrochemical carbon dioxide reduction reaction metal‐nitrogen sites metal‐nitrogen containing macrocyclic complexes metal organic frameworks Zeolitic imidazolate frameworks Carbon material doped with metal‐nitrogen sites
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Computational Studies of Photocatalysis with Metal-Organic Frameworks 被引量:2
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作者 Xin-Ping Wu Indrani Choudhuri Donald G.Truhlar 《Energy & Environmental Materials》 2019年第4期251-263,共13页
Metal–organic frameworks (MOFs) as photocatalysts and photocatalyst supports combine several advantages of homogeneous and heterogeneous catalyses, including stability, post-reaction separation, catalyst reusability,... Metal–organic frameworks (MOFs) as photocatalysts and photocatalyst supports combine several advantages of homogeneous and heterogeneous catalyses, including stability, post-reaction separation, catalyst reusability,and tunability, and they have been intensively studied for photocatalytic applications. There are several reviews that focus mainly or even entirely on experimental work. The present review is intended to complement those reviews by focusing on computational work that can provide a further understanding of the photocatalytic properties of MOF photocatalysts. We first present a summary of computational methods, including density functional theory, combined quantum mechanical and molecular mechanical methods, and force fields for MOFs. Then, computational investigations on MOF-based photocatalysis are briefly discussed. The discussions focus on the electronic structure, photoexcitation, charge mobility, and photoredox catalysis of MOFs, especially the widely studied Ui O-66-based MOFs. 展开更多
关键词 COMPUTATION metal doping metal-organic framework PHOTOCATALYSIS QM/MM
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DFT Investigation of the Hydrogen Adsorption on Graphene and Graphene Sheet Doped with Osmium and Tungsten 被引量:1
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作者 Balqees Suliman Alshareef 《Open Journal of Physical Chemistry》 2020年第4期197-204,共8页
Significant interest has been focused on graphene materials for their unique properties as Hydrogen storage materials. The development of their abilities by modifying their configuration with doped or decorated transi... Significant interest has been focused on graphene materials for their unique properties as Hydrogen storage materials. The development of their abilities by modifying their configuration with doped or decorated transition metals </span><span style="font-family:Verdana;">was also of great interest. In this work</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> using the DFT/B3LYP/6-31G/LanL2DZ</span><span style="font-family:Verdana;"> level of theory, graphene sheet (GS) as one of the materials of interest was doped with two transition metals, Osmium (Os) and Tungsten (W). Two active sites on the GS were tested (C4 and C16) resulted into adsorbed systems, H2@C4-GS and H2@C16-GS. C16 position showed the largest adsorption energy compared to that at C4. Therefore, C4 was replaced by the two metals and two adsorbed systems were formed</span><span style="font-family:Verdana;">: </span><span style="font-family:Verdana;">H</span><sub><span style="font-family:Verdana;vertical-align:sub;">2</span></sub><span style="font-family:Verdana;">@Os-GS and H2@W-GS. The binding energy of H</span><sub><span style="font-family:Verdana;vertical-align:sub;">2</span></sub><span style="font-family:Verdana;">@Os-GS was found to be greater than that of H2@W-GS. 展开更多
关键词 Graphene Sheet Doping metal OSMIUM TUNGSTEN Density Functional Theory Adsorption The Highest Occupied Molecular Orbital The Lowest Unoccupied Molecular Orbital
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