N-doped CuCo2S4 with bifunctional ORR/OER activities as cathode material in Zn-air battery

• Published in: Inorganic chemistry communications Vol. 181; p. 115223
• Main Authors: Wang, Xinjiao, Zhang, Xinyu, Wang, Yun, Xu, Xinxin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2025
• Subjects: Coordination polymer; CuCo2S4; Electrocatalysis; N-doping; ORR/OER; Zn-air battery; Electrocatalysis; Zn-air battery; Coordination polymer; N-doping; CuCo2S4; ORR/OER
• ISSN: 1387-7003
• DOI: 10.1016/j.inoche.2025.115223

Zn-air battery is an environment friendly energy conversion and storage instrument with low operation cost. Its charge/discharge is realized through oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), respectively. So, the activity of bifunctional electrocatalyst determines performance of Zn-air battery in great extent. As a ternary metal sulfide with spinel structure, CuCo2S4 shows both ORR and OER activity. But the sluggish ORR and OER kinetics cannot satisfy the requirement of zinc-air battery completely in practical application. To improve ORR/OER activity, N-doped CuCo2S4 (N-CuCo2S4) is synthesized, which shows typical 4e-character in ORR with half-wave potential 0.84 V. In OER, it merely consumes 240 mV to acquire 10 mA cm−2. Theoretical calculation illustrates improved ORR/OER activity originates from intensified interaction with relevant oxygen species. Zn-air battery is constructed with N-CuCo2S4 as cathode material. Its open circuit voltage achieves 1.42 V with power density 160.2 mW cm−2. When discharge at 10 mA cm−2, specific capacitance and energy density are 832.6 mAh g−1Zn and 984.9 Wh kg−1Zn. The present study not only provides an effective way to enhance ORR/OER activities for ternary metal sulfide, but also clarifies the mechanism during this process. Based on coordination polymer, N-doped CuCo2S4 is synthesized, which shows excellent ORR/OER activities. When employed as cathode material, Zn-air battery exhibits perfect charge/discharge performance. [Display omitted] •Based on coordination polymer, N-CuCo2S4 was synthesized.•N-CuCo2S4 showed ORR and OER activity in alkaline electrolyte.•The connection between structure and activity was studied.•Zn-air battery was constructed on N-CuCo2S4.