La掺杂对NiCo/Cu的显微结构及电催化性能的影响

Effect of La Doping on Microstructure and Electrocatalytic Performance of NiCo / Cu Electrode

摘要:

本文通过简单的一步水热法在铜片上负载La掺杂NiCo合金制备催化电极。借助XRD、FESEM、循环伏安测试研究了溶液中Ni2 +/Co2 +摩尔比、La掺杂量对试样物相、显微结构、负载量及甲醇电催化氧化性能的影响。研究表明: Co元素的引入使生长的颗粒粒径增大，负载量显著增加。随着溶液中Co2+量的增加，峰电流密度先增后减。Ni2+/Co2+摩尔比在8：2时性能良好，与Ni/Cu 电极相比，峰电流密度提升了约28.4%。La的掺杂使NiCo颗粒呈现多边化，进而影响电化学性能，随着La的掺杂量的增加，峰电流密度先升后降，掺杂0.1 mmol/L La3+的试样获得良好的性能，峰电流密度达到了50.36 mA/cm2，2000次循环后仍保留近初始的100%，具有优异的稳定性，有望用于直接甲醇燃料电池（DMFC）阳极材料。

Abstract:

In this study, catalytic electrode prepared via a simple one-step hydrothermal method to load La-doped NiCo on a copper sheet. XRD, FESEM, cyclic voltammetry and other tests were used to study the influence of the molar ratio of NiCo salt and the amount of La doped on the microstructure of the sample and the electrocatalytic oxidation performance of methanol. The results show that the introduction of Co increases the particle size, and the performance get better when the molar ratio of Ni2 +/Co2 + in the solution is 8: 2. The doping of La affect the morphology of the particles. As the doping amount of La increases, the peak current density can increase and then decrease. The sample doped with 10-4 mol/L La obtained superior performance; the peak current density reached 50.36 mA/cm2. After 2000 cycles, it retained nearly 100% of the initial current density. It has good stability and can be used with direct methanol fuel cell (DMFC).