A simple method for preparation of presulfided eggshell CoMoS/γ-Al2O3 catalysts with sharp boundary is developed, through which the eggshell thicknesses of Co and Mo could be easily regulated by controlling the impre...A simple method for preparation of presulfided eggshell CoMoS/γ-Al2O3 catalysts with sharp boundary is developed, through which the eggshell thicknesses of Co and Mo could be easily regulated by controlling the impregnation time. According to the results characterized by EDS, XRD, HRTEM and FT-IR of adsorbed CO, the active component structures, the nature and/or the amount of active sites on the eggshell catalyst are similar to these on the uniform catalyst. The evaluation results of the catalytic performance in selective hydrodesulfurization （HDS） of FCC gasoline show the presence of significant internal diffusion inhibition effect on HDS of S-compounds especially in the uniform catalyst. Compared with uniform catalyst, the eggshell catalyst could remarkably reduce such an internal diffusion inhibition effect due to a shortened diffusion path of the reactants, thus showing higher HDS activity and selectivity.展开更多
Development of earth-abundant electrocatalysts, particularly for high-efficiency hydrogen evolution reaction （HER） under benign conditions, is highly desired, but still remains a serious challenge. Herein, we report...Development of earth-abundant electrocatalysts, particularly for high-efficiency hydrogen evolution reaction （HER） under benign conditions, is highly desired, but still remains a serious challenge. Herein, we report a high-performance amorphous CoMoS4 nanosheet array on carbon cloth （CoMoS4 NS/CC）, prepared by hydrothermal treatment of a Co（OH）F nanosheet array on a carbon cloth （Co（OH）F NS/CC） in （NH4）2MoS4 solution. As a three-dimensional HER electrode, CoMoS4 NS/CC exhibits remarkable activity in 1.0 M phosphate buffer saline （pH 7）, only requiring an overpotential of 183 mV to drive a geometrical current density of 10 mA·cm-2. This overpotential is 140 mV lower than that for Co（OH）F NS/CC. Notably, this electrode also shows outstanding electrochemical durability and nearly 100% Faradaic efficiency. Density functional theory calculations suggest that CoMoS4 has a more favorable hydrogen adsorption free energy than Co（OH）F.展开更多
基金supported by grants from the Major State Basic Research Development Program of China ("973" Program, 2010CB226905)the National Natural Science Foundation of China (Grant Nos. 21006128 and 21106185)+2 种基金the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20100133120007)the Shandong Provincial Natural Science Foundation of China (ZR2011BQ002)the Fundamental Research Funds for the Central Universities and the Graduate Innovation Project of China University of Petroleum (Grant No. CXZD11-06)
文摘A simple method for preparation of presulfided eggshell CoMoS/γ-Al2O3 catalysts with sharp boundary is developed, through which the eggshell thicknesses of Co and Mo could be easily regulated by controlling the impregnation time. According to the results characterized by EDS, XRD, HRTEM and FT-IR of adsorbed CO, the active component structures, the nature and/or the amount of active sites on the eggshell catalyst are similar to these on the uniform catalyst. The evaluation results of the catalytic performance in selective hydrodesulfurization （HDS） of FCC gasoline show the presence of significant internal diffusion inhibition effect on HDS of S-compounds especially in the uniform catalyst. Compared with uniform catalyst, the eggshell catalyst could remarkably reduce such an internal diffusion inhibition effect due to a shortened diffusion path of the reactants, thus showing higher HDS activity and selectivity.
基金This work was supported by the National Key Sdentific Instrument and Equipment Development Project of China （No. 21627809）, the National Natural Science Foundation of China （Nos. 21375047, 21377046, 21405059, 21575137, 21575050, and 21601064）, Natural Science Foundation of Shandong Province （Nos. ZR2016JL013 and ZR2016BQ10）, Graduate Innovation Foundation of University of Jinan （No. YCXB15004）, and the Special Foundation for Taishan Scholar Professorship of Shandong Province （No. ts20130937）.
文摘Development of earth-abundant electrocatalysts, particularly for high-efficiency hydrogen evolution reaction （HER） under benign conditions, is highly desired, but still remains a serious challenge. Herein, we report a high-performance amorphous CoMoS4 nanosheet array on carbon cloth （CoMoS4 NS/CC）, prepared by hydrothermal treatment of a Co（OH）F nanosheet array on a carbon cloth （Co（OH）F NS/CC） in （NH4）2MoS4 solution. As a three-dimensional HER electrode, CoMoS4 NS/CC exhibits remarkable activity in 1.0 M phosphate buffer saline （pH 7）, only requiring an overpotential of 183 mV to drive a geometrical current density of 10 mA·cm-2. This overpotential is 140 mV lower than that for Co（OH）F NS/CC. Notably, this electrode also shows outstanding electrochemical durability and nearly 100% Faradaic efficiency. Density functional theory calculations suggest that CoMoS4 has a more favorable hydrogen adsorption free energy than Co（OH）F.
