不同Pt与Ni质量比的Pt-Ni复合电极析氢性能实验

Experimental hydrogen precipitation performance of Pt-Ni composite electrodes with different Pt/Ni mass ratios

为降低PEM制氢Pt电极成本,采用电化学沉积法制备以泡沫镍为基材微量Pt沉积的Pt-Ni复合电极。采用扫描电子显微镜、X射线衍射仪、X射线光谱仪对制备的Pt-Ni复合电极进行表征,采用电化学工作站和PEM电解池对Pt与Ni质量比分别为1∶7、1∶11、1∶12、1∶14和1∶23的5种不同复合电极及泡沫镍电极的析氢性能进行电化学对比分析实验和PEM制氢对比实验。结果表明:以泡沫镍为基材,采用电化学沉积法制备的Pt-Ni复合电极性能稳定,沉积Pt质量的多少对Pt-Ni复合电极的析氢性能有较大影响;存在一个最佳Pt与Ni质量比,实验条件下的最佳Pt与Ni质量比为1∶12,沉积Pt量过多和过少都会使其析氢性能降低,过多造成的Pt沉积堆叠相比较少对析氢性能的影响更加明显。在制备微量Pt沉积的Pt-Ni复合电极时,要坚持以最佳Pt与Ni质量比为基准和沉积Pt量“宁少毋多”的原则,实际工程应用中应避免“沉积Pt量越多电极性能越好”的误区。

To reduce the cost of Pt electrode for hydrogen production by PEM electrolysis,the Pt-Ni composite electrode was prepared by electrochemical deposition method using nickel foam as substrate.The prepared Pt-Ni composite electrode was characterized by scanning electron microscope,X-ray diffractometer,and X-ray spectrometer.The hydrogen evolution property of five composite electrodes with different Pt/Ni mass ratios of 1∶7,1∶11,1∶12,1∶14 and 1∶23 were carried out by electrochemical workstation and PEM electrolytic cell.The experimental results show that the Pt-Ni composite electrode prepared by the electrochemical deposition method with nickel foam as the substrate has stable properties,and the amount of deposited Pt has a great influence on the hydrogen evolution property of the Pt-Ni composite electrode.There is an optimal Pt/Ni mass ratio and the best Pt/Ni mass ratio under experimental conditions is m(Pt)∶m(Ni)=1∶12.With either too much or too little Pt deposition,the hydrogen evolution property will be reduced,and the impact of too much Pt deposition stacking on the hydrogen evolution property will be more obvious.In the preparation of Pt-Ni composite electrodes with trace Pt deposition,the principle that the best Pt/Ni mass ratio should be used as a benchmark and the amount of Pt deposited should be"less rather than more"should be kept,while the misconception of"the more Pt deposited the better the electrode property"should be avoided in practical engineering applications.