水溶液中电沉积制备LaMg2Ni9储氢合金

Electrodeposition of LaMg2Ni9 Hydrogen Storage Alloys in Aqueous Bath

摘要:

利用水溶液电沉积法制备LaMg₂Ni₉储氢合金膜,通过测定合金膜的循环伏安曲线(CV)、交流阻抗(EIS)、Tafel极化曲线等研究其的电化学性能,采用扫描电镜(SEM)、X-射线衍射(XRD)、能谱(EDS)对合金膜表面形貌、结构及组成进行研究。结果表明：电沉积电流密度为40A/dm₂时,LaMg₂Ni₉合金膜的表面粗糙并伴有裂纹,析氢电流为5.37A/dm₂,表观活化自由能△G_≠最低为47.26kJ/mol,证明合金膜良好的析氢性能；吸附值Q为0.091μF?cm_-2达到最大值,表明合金膜具有较高的储氢性能。

关键词:LaMg₂Ni₉;析氢;储氢;电沉积

Abstract:

The film of LaMg₂Ni₉ Hydrogen Storage alloy is prepared in aqueous solution. The electrochemical performance were studied by cyclic voltammetry(CV), electrochemical impedance spectroscopy(EIS) and Tafel polarization curve. Sanning electronic microscope(SEM), X-ray diffractometer(XRD) and energy distribution spectrum(EDS)were used to research the phase structure, component and composition. The results showed that the LaMg₂Ni₉ film has a crudity surface with a cracke. The alloy film obtained at 40A/dm₂, the△G_≠reaches to 47.26kJ/mol, the Hydrogen evolution current density j_o is 5.37 A/cm₂, indicating it has higher hydrogen evolution activity; the electrode adsorption degree Q is 0.091F/cm₂, indicating the film has better hydrogen storage function.

Key words:LaMg₂Ni₉;hydrogen evolution;hydrogen storage;Electrodeposition