A novel solid-gas reaction preparation technology was used to adjust the composition and microstructure of the composite crystal materials by changing the preparation parameters. Compared with the commonly used sol-ge...A novel solid-gas reaction preparation technology was used to adjust the composition and microstructure of the composite crystal materials by changing the preparation parameters. Compared with the commonly used sol-gel method, acid base neutralization sedimentation method, hydrothermal method, and gas phase deposition method, the technology was relatively simplified and the elemental composition was controllable, without the use of openings and additives. A kind of multi-element composite porous metal oxide was obtained by pre-intercalation and decarburization. In order to increase the porosity of MoO3 material and promote the adsorption and diffusion of reactant molecules, the microstructure of MoO3 was studied. The preparation process of porous molybdenum trioxide by solid gas combination process was discussed, which provides an innovative idea for the design and preparation of new materials with a large specific surface area and other desirable properties.展开更多
Constructing atomically dispersed active sites with densely exposed and dispersed double metal-Sx catalytic sites for favorable OER catalytic activity remains rare and challenging.Herein,we design and construct a Fe_(...Constructing atomically dispersed active sites with densely exposed and dispersed double metal-Sx catalytic sites for favorable OER catalytic activity remains rare and challenging.Herein,we design and construct a Fe_(1)S_(x)@Co_(3)S_(4) electrocatalyst with Fe single atoms epitaxially confined in Co_(3)S_(4) nanosheets for catalyzing the sluggish alkaline oxygen evolution reaction(OER).Consequently,in ultralow concentration alkaline solutions(0.1 mol/L KOH),such a catalyst is highly active and robust for OER with low overpotentials of 300 and 333 mV at current densities of 10 and 30 mA/cm^(2),respectively,accompanying long-term stability without significant degradation even for 350 h.In addition,Fe_(1)S_(x)@Co_(3)S_(4) shows a turnover frequency(TOF)value of 0.18 s−1,nearly three times that of Co_(3)S_(4)(0.07 s−1),suggesting the higher atomic utilization of Fe single atoms.Mössbauer and in-situ Raman spectra confirm that the OER activity of Fe_(1)S_(x)@Co_(3)S_(4) origins from a thin catalytic layer of Co(Fe)OOH that interacts with trace-level Fe species in the electrolyte,creating dynamically stable active sites.Combined with experimental characterizations,it suggests that the most active S-coordinated dual-metal site configurations are 2S-bridged(Fe-Co)S4,in which Co-S and Fe-S moieties are shared with two S atoms,which can strongly regulate the adsorption energy of reaction intermediates,accelerating the OER reaction kinetics.展开更多
基金Funded by National Natural Science Foundation of China(No.516722040)。
文摘A novel solid-gas reaction preparation technology was used to adjust the composition and microstructure of the composite crystal materials by changing the preparation parameters. Compared with the commonly used sol-gel method, acid base neutralization sedimentation method, hydrothermal method, and gas phase deposition method, the technology was relatively simplified and the elemental composition was controllable, without the use of openings and additives. A kind of multi-element composite porous metal oxide was obtained by pre-intercalation and decarburization. In order to increase the porosity of MoO3 material and promote the adsorption and diffusion of reactant molecules, the microstructure of MoO3 was studied. The preparation process of porous molybdenum trioxide by solid gas combination process was discussed, which provides an innovative idea for the design and preparation of new materials with a large specific surface area and other desirable properties.
基金National Natural Science Foundation of China(Nos.21501096,22075223)Natural Science Foundation of Jiangsu Province,China(Nos.BK20150086,BK20201120)+4 种基金Foundation of the Jiangsu Education Committee,China(No.15KJB150020)Six Talent Peaks Project in Jiangsu Province,China(No.JY-087)Innovation Project of Jiangsu Province,Excellent Scientific and Technological Innovation Team of Colleges and Universities of Jiangsu Province,China(No.SUJIAOKE 2021 No.1)Key Subject of Ecology of Jiangsu Province,China(No.SUJIAOYANHAN 2022 No.2)Project of the Scientific and Technological Innovation Team of Nanjing,China(No.NINGJIAOGAOSHI 2021 No.16).
文摘Constructing atomically dispersed active sites with densely exposed and dispersed double metal-Sx catalytic sites for favorable OER catalytic activity remains rare and challenging.Herein,we design and construct a Fe_(1)S_(x)@Co_(3)S_(4) electrocatalyst with Fe single atoms epitaxially confined in Co_(3)S_(4) nanosheets for catalyzing the sluggish alkaline oxygen evolution reaction(OER).Consequently,in ultralow concentration alkaline solutions(0.1 mol/L KOH),such a catalyst is highly active and robust for OER with low overpotentials of 300 and 333 mV at current densities of 10 and 30 mA/cm^(2),respectively,accompanying long-term stability without significant degradation even for 350 h.In addition,Fe_(1)S_(x)@Co_(3)S_(4) shows a turnover frequency(TOF)value of 0.18 s−1,nearly three times that of Co_(3)S_(4)(0.07 s−1),suggesting the higher atomic utilization of Fe single atoms.Mössbauer and in-situ Raman spectra confirm that the OER activity of Fe_(1)S_(x)@Co_(3)S_(4) origins from a thin catalytic layer of Co(Fe)OOH that interacts with trace-level Fe species in the electrolyte,creating dynamically stable active sites.Combined with experimental characterizations,it suggests that the most active S-coordinated dual-metal site configurations are 2S-bridged(Fe-Co)S4,in which Co-S and Fe-S moieties are shared with two S atoms,which can strongly regulate the adsorption energy of reaction intermediates,accelerating the OER reaction kinetics.
