Enhancing lithium storage capacity of ZnO anodes through Ni ₃ZnC_0.7 incorporation

In this study, lithium storage capacity of ZnO anodes was significantly enhanced by Ni₃ZnC_0.7 incorporation. A core-shell ZnO- Ni₃ZnC_0.7 -C nanocomposite was synthesized through a simple thermal decomposition of Zn/Ni-based organic precursors, and the structural and electrochemical characteristics of the composite were investigated in detail. At a current density of 0.20 mA cm^-2, the ZnO-Ni₃ZnC_0.7 -C composite exhibited an initial discharge capacity of 1120 mAh g^-1 and retained a discharge capacity of 372 mAh g^-1 at the 50th cycle. The latter value was at least twice larger than that of the ZnO-C composite prepared by a similar process. The enhanced lithium storage capacity was believed to arise from the catalytic and conductive effects of the Ni₃ZnC_0.7 phase. The reversible capacity of the ZnO-Ni₃ZnC_0.7-C composite could be tuned by varying the molar ratio of Zn/Ni in the precursors. The present findings opened the possibility of preparing anode materials for lithium-ion batteries via a molecular design on organic precursors.