镍基析氢电极在碱性溶液中析氢行为

Electrochemical performance of porous Ni-based electrodes for hydrogen evolution reaction in alkaline solution

采用元素粉末反应合成法制备多孔Ni_3Al-Mo电极。采用扫描电镜(SEM)和X射线衍射(XRD)对多孔Ni_3Al-Mo电极的孔结构进行表征,通过极化曲线和电化学阻抗技术表征多孔Ni_3Al-Mo电极的电解析氢行为。结果表明:多孔Ni_3Al-Mo电极孔隙率为47%,最大孔隙为2.7μm,平均孔隙约2.1μm。与多孔Ni_3Al电极和多孔Ni电极相比,多孔Ni_3Al-Mo电极具有较低的析氢过电位和较高的交换电流密度,表明多孔Ni_3Al-Mo电极具有较高的析氢活性;经过阳极处理后,多孔Ni_3Al-Mo电极的析氢活性可以恢复到原来的大小,且连续电解120 h后,析氢过电位变化不大,表明多孔Ni_3Al-Mo电极具有优异的电化学稳定性。

Objective of this work was to investigate the electrochemical performance of porous Ni_3Al-Mo electrodes for hydrogen evolution reaction using cathodic polarization and impedance spectroscopy techniques. The morphology of the porous Ni_3Al-Mo electrode was characterized by scanning electron mircosope（SEM） and X ray diffration（XRD）. The results show that Ni_3Al-Mo electrode has a large porosity of 47%, the maximum pore size of 2.7 μm, the mean pore size of 2.1 μm and lower overpotential, higher exchange current density comparing to the porous Ni_3Al and porous Ni electrodes. After anodic treatment, the polarization curve becomes almost the same as the one recorded before the anodic treatment. The activity of the porous Ni_3Al-Mo electrode does not change much after the current interruptions, even after 120 h, which indicates that porous Ni_3Al-Mo electrode has higher hydrogen evolution activity and better electrocatalytic performance.