Precisely controlling the crystalline phase structure and exposed facets at the atomic level opens up a new avenue for efficient catalyst design.Along this line,we report an unconventional face-centered cubic(fcc)Ru w...Precisely controlling the crystalline phase structure and exposed facets at the atomic level opens up a new avenue for efficient catalyst design.Along this line,we report an unconventional face-centered cubic(fcc)Ru with twinned structure and stacking-fault defects as a competent electrocatalyst towards alkaline hydrogen oxidation reaction(HOR),which is now a major obstacle for the commercialization of anion exchange membrane fuel cells(AEMFC).With conventional hexagonal close packing(hcp)Ru as the counterpart,a novel scope from the phase-engineering is introduced to identify the activity origin and provide fundamental understanding of the sluggish HOR kinetics in alkaline medium.Systematic electrochemical analysis assisted by deconvoluting the hydrogen(H)desorption peaks indicates the superior performance of fcc Ru origins from the structure defects and higher proportion of the most active sites.DFT calculations,together with CO-stripping voltammograns further corroborate the stronger hydroxyl species(OH^(*))affinity lead to the higher activity on these sites.Meanwhile,it also demonstrates the H^(*)adsorption/desorption on polycrystalline Ru among the conventional"hydrogen region"is accompanied by the surface bound OH^(*)in alkaline medium,which is of great significance for subsequent alkaline HOR exploration and catalyst design.展开更多
Local phase transition in transition metal dichalcogenides (TMDCs) by lithiumintercalation enables the fabrication of high-quality contact interfaces in twodimensional(2D) electronic devices. However, controlling the ...Local phase transition in transition metal dichalcogenides (TMDCs) by lithiumintercalation enables the fabrication of high-quality contact interfaces in twodimensional(2D) electronic devices. However, controlling the intercalation oflithium is hitherto challenging in vertically stacked van der Waalsheterostructures (vdWHs) due to the random diffusion of lithium ions in thehetero-interface, which hinders their application for contact engineering of 2DvdWHs devices. Herein, a strategy to restrict the lithium intercalation pathwayin vdWHs is developed by using surface-permeation assisted intercalationwhile sealing all edges, based on which a high-performance edge-contact MoS_(2)vdWHs floating-gate transistor is demonstrated. Our method avoids intercalationfrom edges that are prone to be random but intentionally promotes lithiumintercalation from the top surface. The derived MoS_(2) floating-gatetransistor exhibits improved interface quality and significantly reduced subthresholdswing (SS) from >600 to 100 mV dec^(–1). In addition, ultrafast program/erase performance together with well-distinguished 32 memory statesare demonstrated, making it a promising candidate for low-power artificialsynapses. The study on controlling the lithium intercalation pathways in 2DvdWHs offers a viable route toward high-performance 2D electronics for memoryand neuromorphic computing purposes.展开更多
Syngas(CO+H_(2))is the incredibly important feedstock for producing synthetic fuels and various value-added chemicals.CO_(2) electrochemical reduction to syngas is an environmental-friendly and sustainable approach,bu...Syngas(CO+H_(2))is the incredibly important feedstock for producing synthetic fuels and various value-added chemicals.CO_(2) electrochemical reduction to syngas is an environmental-friendly and sustainable approach,but still challenging to produce tunable syngas with a wide ratio of CO+H_(2).Herein,by modulating the structure and phase,we have successfully obtained a series of copper-indium(Cu-ln)catalysts,which are efficient for producing syngas with tunable CO+H_(2) ratios.A series of Culn bimetallic catalysts with different structures from hollow sphere to two-layer hollow sphere and different phases from CuO to CU_(2)O are developed.We find that the CO and H2 are the only gaseous products,in which the CCD/H_(2) ratios can be readily tuned from 1.2±0.1 to 9.0±1.5 by simply controlling the thermal annealing temperature.It also exhibits high durability during a 10-h test.The unique performance is attributed to the modulated In enrichment on the Cu surfaces during the CO_(2) reduction reaction,which causes the differences in binding energies for key reaction intermediates,thus resulting in the tunable composition of syngas.The present work emphasizes a simple yet efficient phase and structure modulating strategy for designing potential electrocatalysts for producing syngas with widely tunable CO+H_(2) ratios.展开更多
基金financially supported by the National Natural Science Foundation(91963109)the Fundamental Research Funds for the Central Universities(2019kfyRCPY100)supported by the Analytical and Testing Center of Huazhong University of Science&Technology。
文摘Precisely controlling the crystalline phase structure and exposed facets at the atomic level opens up a new avenue for efficient catalyst design.Along this line,we report an unconventional face-centered cubic(fcc)Ru with twinned structure and stacking-fault defects as a competent electrocatalyst towards alkaline hydrogen oxidation reaction(HOR),which is now a major obstacle for the commercialization of anion exchange membrane fuel cells(AEMFC).With conventional hexagonal close packing(hcp)Ru as the counterpart,a novel scope from the phase-engineering is introduced to identify the activity origin and provide fundamental understanding of the sluggish HOR kinetics in alkaline medium.Systematic electrochemical analysis assisted by deconvoluting the hydrogen(H)desorption peaks indicates the superior performance of fcc Ru origins from the structure defects and higher proportion of the most active sites.DFT calculations,together with CO-stripping voltammograns further corroborate the stronger hydroxyl species(OH^(*))affinity lead to the higher activity on these sites.Meanwhile,it also demonstrates the H^(*)adsorption/desorption on polycrystalline Ru among the conventional"hydrogen region"is accompanied by the surface bound OH^(*)in alkaline medium,which is of great significance for subsequent alkaline HOR exploration and catalyst design.
基金National Key Research and Development Program of China,Grant/Award Number:2023YFB4502200National Natural Science Foundation of China,Grant/Award Numbers:52372149,U21A2069+2 种基金Innovation Project of Optics Valley Laboratory,Grant/Award Number:OVL2023PY007Guangdong HUST Industrial Technology Research Institute,Guangdong Provincial Key Laboratory of Manufacturing Equipment Digitization,Grant/Award Number:2023B1212060012Interdiciplinary Research Program of HUST,Grant/Award Number:2024JCYJ008。
文摘Local phase transition in transition metal dichalcogenides (TMDCs) by lithiumintercalation enables the fabrication of high-quality contact interfaces in twodimensional(2D) electronic devices. However, controlling the intercalation oflithium is hitherto challenging in vertically stacked van der Waalsheterostructures (vdWHs) due to the random diffusion of lithium ions in thehetero-interface, which hinders their application for contact engineering of 2DvdWHs devices. Herein, a strategy to restrict the lithium intercalation pathwayin vdWHs is developed by using surface-permeation assisted intercalationwhile sealing all edges, based on which a high-performance edge-contact MoS_(2)vdWHs floating-gate transistor is demonstrated. Our method avoids intercalationfrom edges that are prone to be random but intentionally promotes lithiumintercalation from the top surface. The derived MoS_(2) floating-gatetransistor exhibits improved interface quality and significantly reduced subthresholdswing (SS) from >600 to 100 mV dec^(–1). In addition, ultrafast program/erase performance together with well-distinguished 32 memory statesare demonstrated, making it a promising candidate for low-power artificialsynapses. The study on controlling the lithium intercalation pathways in 2DvdWHs offers a viable route toward high-performance 2D electronics for memoryand neuromorphic computing purposes.
基金supported by the Ministry of Science and Technology(Nos.2017YFA0208200 and 2016YFA0204100)the National Natural Science Foundation of China(No.21905188),China Postdoctoral Science Foundation(No.2019M651937)+3 种基金The Project of Scientific and Technologic Infrastructure of Suzhou(SZS201905)Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices,Soochow University(No.KJS2019)Young Thousand Talented Program,Jiangsu Province Natural Science Fund for Distinguished Young Scholars(No.BK20170003)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),and the start-up supports from Xiamen University.
文摘Syngas(CO+H_(2))is the incredibly important feedstock for producing synthetic fuels and various value-added chemicals.CO_(2) electrochemical reduction to syngas is an environmental-friendly and sustainable approach,but still challenging to produce tunable syngas with a wide ratio of CO+H_(2).Herein,by modulating the structure and phase,we have successfully obtained a series of copper-indium(Cu-ln)catalysts,which are efficient for producing syngas with tunable CO+H_(2) ratios.A series of Culn bimetallic catalysts with different structures from hollow sphere to two-layer hollow sphere and different phases from CuO to CU_(2)O are developed.We find that the CO and H2 are the only gaseous products,in which the CCD/H_(2) ratios can be readily tuned from 1.2±0.1 to 9.0±1.5 by simply controlling the thermal annealing temperature.It also exhibits high durability during a 10-h test.The unique performance is attributed to the modulated In enrichment on the Cu surfaces during the CO_(2) reduction reaction,which causes the differences in binding energies for key reaction intermediates,thus resulting in the tunable composition of syngas.The present work emphasizes a simple yet efficient phase and structure modulating strategy for designing potential electrocatalysts for producing syngas with widely tunable CO+H_(2) ratios.
