Among the cathode materials for zinc-ion batteries, manganese oxides have been extensively studied. Thermal decomposition method was adopted to synthesize the Ni-doped δ-MnO2 material, called as NixMn1-xO2. The electrochemical performance and energy storage mechanism of NixMn1-xO2 were studied in 2M ZnSO4 + 0.2M MnSO4 electrolyte. Nickel doping can significantly improve the electrochemical activity of δ-MnO2. Therefore, Ni-doped δ-MnO2 shows better electrochemical cycling performance than δ-MnO2. At 100 mA g−1, NixMn1-xO2 (x=0.2) the specific capacity of 280mAh g−1 in the second circle, and the corresponding voltage platform is 1.36V and 1.23 two discharge voltage platforms. After 100 cycles, the specific capacity of NixMn1-xO2 (x=0.2) still maintain 167 mAh g−1 at a current density of 100 mA g−1. In addition, we also proved that Zn2+ and H+ are co-intercalated into NixMn1-xO2 during the process of charge and discharge and the electrochemical reaction is highly reversible. This research broadens the thinking of exploring ZIBs cathode materials with good specific capacity and cycle performance.

Oxygen reduction reaction (ORR), as a multielectron electrode reaction, is an important electrochemical reaction in the field of electrochemical energy storage systems. Herein, a new advanced electrochemical laboratory experiment is designed for undergraduates to master the preparation of oxygen reduction catalytic electrode. Students can use rotating disk electrode (RDE) and rotating ring-disk electrode (RRDE) to evaluate the properties of the ORR catalyst and expound the kinetics mechanism of multielectron electrode reaction. By fitting the K–L curve to calculate the electron transfer number, the ORR reaction path of the industrial Pt/C catalyst in the KOH electrolyte can be determined. The basic kinetic parameters of the ORR and the intermediate content will help students to deeply understand the Butler–Volmer equation. The new teaching experiment focuses on the integration of frontier scientific research and undergraduate teaching. This experiment may enhance students’ interest in learning electrochemistry and broadening their horizons as well as help them understand the ORR mechanism involved in modern electrochemical testing technology. In addition, the student’s ability of data processing and comprehensive analysis will be improved. This new comprehensive experiment is a fundamental, innovative, and systematic physical chemistry experiment.

Although magnesium rechargeable battery (MRB) raise considerable attention, the research on MRBs is still in its infancy. One of issues is that magnesium ions is difficult to reversibly (de)-intercalate in...

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