ZnO/ZnO-Bi_2O_3 nanocomposite as an anode material for Ni-Zn rechargeable battery

摘要

A novel ZnO/ZnO-Bi_2O_3 nanocomposite was prepared by a homogeneous precipitation method. The nucleation sites, namely ZnO-Bi_2O_3 particles with nominal chemical composition of (ZnO)0.94(Bi2O3)0.06, were prepared by ball milling and subsequent annealing treatment. The as-synthesized materials were characterized by XRD, SEM and electrochemical measurements. Compared with single ZnO, the ZnO/ZnO-Bi_2O_3 nanocomposite show better cycling stability and higher discharge capacity. When the content of ZnO-Bi_2O_3 was 15 wt.%, the discharge capacity of ZnO/ZnO-Bi_2O_3 nanocomposite hardly declined over 60 cycling test, the average discharge capacity reached 590.2 mAh g~(-1). Cyclic voltammograms clearly illuminated that the added ZnO-Bi_2O_3 particles could decrease electrode polarization, maintain the electrochemical activity, and enhance the discharge capacity of ZnO.