Mg-Ni合金的电沉积研究

Investigation of Electrodeposition of Mg-Ni Alloy

采用电沉积的方法从非水体系和水体系中制备出镁-镍合金,并且制备了氢氧化镍。X射线衍射、扫描电镜和能谱分析结果表明,两种体系的沉积层均含有黑色非晶态的镁-镍合金,呈结瘤状的微观形貌。初步研究了沉积机理以及镁-镍合金的电化学性能,结果表明,镁镍合金在两种体系中沉积析出电位均为-2.0 V(vs SCE),沉积过程不可逆,非水体系的沉积较水体系困难。水体系脉冲条件下沉积的镁-镍合金氧化还原可逆性良好,其氢扩散系数很大,与氢氧化镍组成电池的工作电压较大,是一类良好的镍氢电池负极材料。

Mg-Ni alloys were synthesized from nonaqueous and aqueous systems by the method of electrodeposition, and nickelous hydroxide was also prepared. The results of X-ray diffraction （XRD） , scanning electron microscopy （SEM） and energy spectrum analysis indicated that all the deposition layers in the two systems contained black amorphous Mg-Ni alloy with nodular microstructure. The investigation of the deposition mechanism and electrochemical properties of Mg-Ni alloy showed that the deposition potential of Mg-Ni alloy in the two systems was - 2.0 V （ vs SCE） and the deposition process was irreversible. The deposition in the nonaqueous system was more difficult than in the aqueous system. Mg-Ni alloy deposited under pulse in the aqueous system had good oxidation-reduction reversibility and a large hydrogen diffusion coefficient. The battery consisted of this kind of Mg-Ni alloy and nickelous hydroxide had a high working voltage. As a result, this kind of Mg-Ni alloy was a good cathode material for Ni-MH battery.