TiO2纳米管沉积NiMo合金纳米阵列制备高效HER催化剂

制备高效稳定的非贵金属催化剂对于电解水生产高纯度氢气的发展至关重要。本实验通过简单的阳极氧化法和电沉积方法制备NiMo/TNAs复合催化剂,将NiMo合金颗粒通过电沉积方法稳固包覆于TNAs独特的弯曲有序界面上,当沉积电流和电解液Mo离子浓度变化时,NiMo的沉积状态和催化能力也随之改变,经过研究表明,在沉积电流密度15mA.cm_^-2,Mo离子浓度4g.L_^-1条件下沉积1min制备的样品具有更高的HER催化性能。通过更大活性表面积,更便捷的离子传输通道和增强的结构稳定性,获得了优异的催化活性的NiMo/TNAs电催化剂。NiMo/TNAs催化剂的起始过电位仅为50mV,分别在110mV和227mV低过电势下获得10mA.cm_^-2和100mA.cm_^-2的电流密度。因此得到结论,将NiMo合金颗粒沉积在TNAs纳米阵列,制备NiMo/TNAs催化剂为制备廉价高效电催化剂提供了新途径。

Preparation of highly efficient HER catalyst by TNAs deposition of NiMo alloy nanoarray

The preparation of highly efficient and stable non-precious metal catalysts is essential for the development of electrocatalytic water-splitting to produce high-purity hydrogen. In this work, NiMo/TNAs nanohierarchical arrays were constructed by simple anodic oxidation and electrodeposition route, The research of its hybrid cocatalyst is envisioned to bestow more active sites with appropriate crystal engineering and modi?ed electronic properties for enhancing catalytic performance. NiMo alloy is firmly coated on the unique curved and ordered interface of TiO₂ nanotube arrays (TNAs) by electrodeposition, When the deposition current and the concentration of Mo ions in the electrolyte change, the state and catalytic ability of NiMo in TNAs also change,the study proved that the samples prepared by depositing 1 min under the parameters of deposition current density of 15 mA.cm^_-2 and Mo ion concentration of 4g.L^_-1 show higher HER catalytic performance. The electrode exhibits the relatively small onset overpotential of 55 mV and presents an overpotential of 110 mV and 227 mV at 10 mA.cm^_-2 and 100mA.cm^_-2 HER current density, also remained an excellent stability with no performance degradation after scanning for 15h at a constant potential. NiMo alloy particles deposited on the curved sidewalls with uniform distribution of TNAs is demonstrated to be an effective method to prepare the cheap and efficient electrocatalyst.