Ni-Ti-O纳米片/泡沫镍复合电极的显微结构及其电化学性能

Microstructure and Electrochemical Properties of Ni-Ti-O Nanosheets Supported on Ni Foam

摘要:

采用了水热合成和热扩渗结合的方法在三维多孔泡沫镍支架上制备了Ni-Ti-O纳米片层。通过扫描电镜（SEM）、X射线衍射（XRD）、透射电镜（TEM）、高分辨透射电镜（HRTEM）对泡沫镍支架上NiO和Ni-Ti-O纳米结构的微观形貌及物相进行了观察表征和物相分析。用循环伏安法和充放电性能测试探究了复合电极对甲醇的催化氧化性能及其电容性能。结果表明：泡沫镍上生长的Ni-Ti-O纳米片物相组成为NiO和TiO，并且为多晶形态；Ti的渗入会使得NiO纳米片中形成氧空位，并和Ni产生协同作用，使得Ni-Ti-O纳米片/泡沫镍电极的对甲醇氧化的电催化性能优于Ni(OH)2/泡沫镍和NiO/泡沫镍电极；泡沫镍和钛粉质量比（RNi/Ti）为1:24，在电流密度为5 mA?cm-2时，Ni-Ti-O电极的面积比电容值为 2.15 F?cm-2，是纳米Ni(OH)2/泡沫镍电极的3.2倍（0.67 F?cm-2）。

Abstract:

Ni-Ti-O nanosheets were fabricated on 3D porous nickel foam by hydrothermal synthesis and thermal diffusion metallizing. Scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) were used to investigate the micro morphology and phase of NiO and Ni-Ti-O nanostructure. The methanol catalytsis performance and capacitance properties of these electrodes were investigated by cyclic voltammetry and charge- discharge tests. The results show that the phase of Ni-Ti-O nanosheets fabricated on 3D porous nickel foam are NiO and TiO with polycrystalline form; The permeation of Ti result in oxygen vacancies in NiO nanosheets and produce synergistic effect with Ni, which makes that the electrocatalytic property of methanol oxidation of Ni-Ti-O nanosheet electrode is much larger than that of Ni(OH)2 and NiO electrode; When the the mass ratio of Ni foam and Ti powder (RNi/Ti) is 1:24, at a current density of 5 mA?cm-2, the area specific capacitance of Ni-Ti-O electrode is 2.15 F?cm-2, which is 3 times more than that of Ni(OH)2/Ni foam electrode (0.67 F?cm-2).