The dynamic load characteristics of a proton exchange membrane fuel cell（PEMFC） with a dead-ended anode were studied. In a 70 h experiment, the effects of anode pressure, operating temperature, and relative humidity...The dynamic load characteristics of a proton exchange membrane fuel cell（PEMFC） with a dead-ended anode were studied. In a 70 h experiment, the effects of anode pressure, operating temperature, and relative humidity of the cathode on the performances of the fuel cell were investigated. The obtained results show that, with different relative humidity of the cathode at 65 ℃, dynamic loading has little effect on the performances of fuel cell and the electrochemically active surface area（ECSA）. However, the fuel cell operating under dynamic load is unstable when the relative humidity is 50%, and at 50 ℃ with 100% relative humidity, applying a dynamic load has a significant influence on the fuel cell performances. Scanning electron microscopy（SEM） showed that both the upstream and middle catalyst layers of the cell were unchanged, whereas the downstream cathode catalyst layer thinned as a response to dynamic load.展开更多
A desirable methanol oxidation electrocatalyst was fabricated by metal atom diffusion to form an alloy of an assembled three-dimensional （3D） radial nanostructure of SnNi nanoneedles loaded with SnNiPt nanoparticles...A desirable methanol oxidation electrocatalyst was fabricated by metal atom diffusion to form an alloy of an assembled three-dimensional （3D） radial nanostructure of SnNi nanoneedles loaded with SnNiPt nanoparticles （NPs）.Herein,metal atom diffusion occurred between the SnNi support and loaded Pt NPs to form a SnNiPt ternary alloy on the catalyst surface.The as-obtained catalyst combines the excellent catalytic performance of the alloy and advantages of the 3D nanostructure;the SnNiPt NPs,which fused on the surface of the SnNi nanoneedle support,can dramatically improve the availability of Pt during electrocatalysis,and thus elevate the catalytic activity.In addition,the efficient mass transfer of the 3D nanostructure reduced the onset potential.Furthermore,the catalyst achieved a favorable CO poisoning resistance and enhanced stability.After atomic interdiffusion,the catalytic activity drastically increased by 45%,and the other performances substantially improved.These results demonstrate the significant advantage and enormous potential of the atomic interdiffusion treatment in catalytic applications.展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51476119 and 51576147)the Natural Science Foundation of Hubei Province(No.2016CFA041)the Fundamental Research Funds for the Central Universities(No.2017 IVA 031)
文摘The dynamic load characteristics of a proton exchange membrane fuel cell（PEMFC） with a dead-ended anode were studied. In a 70 h experiment, the effects of anode pressure, operating temperature, and relative humidity of the cathode on the performances of the fuel cell were investigated. The obtained results show that, with different relative humidity of the cathode at 65 ℃, dynamic loading has little effect on the performances of fuel cell and the electrochemically active surface area（ECSA）. However, the fuel cell operating under dynamic load is unstable when the relative humidity is 50%, and at 50 ℃ with 100% relative humidity, applying a dynamic load has a significant influence on the fuel cell performances. Scanning electron microscopy（SEM） showed that both the upstream and middle catalyst layers of the cell were unchanged, whereas the downstream cathode catalyst layer thinned as a response to dynamic load.
基金This work was financially supported by the National Natural Science Foundation of China （Nos. 21771140, 21471114, 91122103 and 51271132）.
文摘A desirable methanol oxidation electrocatalyst was fabricated by metal atom diffusion to form an alloy of an assembled three-dimensional （3D） radial nanostructure of SnNi nanoneedles loaded with SnNiPt nanoparticles （NPs）.Herein,metal atom diffusion occurred between the SnNi support and loaded Pt NPs to form a SnNiPt ternary alloy on the catalyst surface.The as-obtained catalyst combines the excellent catalytic performance of the alloy and advantages of the 3D nanostructure;the SnNiPt NPs,which fused on the surface of the SnNi nanoneedle support,can dramatically improve the availability of Pt during electrocatalysis,and thus elevate the catalytic activity.In addition,the efficient mass transfer of the 3D nanostructure reduced the onset potential.Furthermore,the catalyst achieved a favorable CO poisoning resistance and enhanced stability.After atomic interdiffusion,the catalytic activity drastically increased by 45%,and the other performances substantially improved.These results demonstrate the significant advantage and enormous potential of the atomic interdiffusion treatment in catalytic applications.
