The effects of CuO additives as the dendrite suppression and anti-corrosion of the Zn anode in Zn-air batteries

The new copper oxide-zinc composites (CuO–Zn) can be used to relieve the dendrite formation, corrosion reaction, and increase the reversibility of Zn anode. CuO–Zn composites were produced by mixing Zn and additive powders to prevent dendrites and the Zn corrosion and can be easily manufactured technically by simply adding it. To confirm the dendrite suppression, an electrodeposition method was conducted. Surface of Zn anode was analyzed by FE-SEM images and CuO showed a more controlled dendrite morphology than other Cu compounds. After the CuO–Zn electrodes were produced using 0.1, 0.5, 1.0, and 3.0 wt.% CuO in Zn, an H2 gas evolution test was adapted to examine the anti-corrosion. The 0.5 wt.% CuO electrode exhibited the lowest H2 gas evolution. To assess the improved performances, several electrochemical measurements like cathodic overpotential, tafel polarization, cyclic voltammetry, and DC-cycling test (full cell test) were conducted and the 0.5 wt.% CuO mixed Zn electrode showed the best reversibility of all samples and longer cycle life until 19 cycles than 13 cycles of pristine Zn.