In-situ cobalt-nickel alloy catalyzed nitrogen-doped carbon nanotube arrays as superior freestanding air electrodes for flexible zinc-air and aluminum-air batteries

• Published in: Applied catalysis. B, Environmental Vol. 317; p. 121764
• Main Authors: Tian, Wen-Wen, Ren, Jin-Tao, Yuan, Zhong-Yong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.11.2022
• Subjects: Bifunctional electrocatalyst; CoNi alloys; Flexible aluminum-air battery; Flexible zinc-air battery; N-doped carbon nanotube arrays; Bifunctional electrocatalyst; N-doped carbon nanotube arrays; CoNi alloys; Flexible zinc-air battery; Flexible aluminum-air battery
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2022.121764

A flexible air electrode with excellent activity and outstanding stability is highly desirable for metal-air batteries. Herein, the rational design of CoNi alloys derived intertwined N-doped carbon nanotube arrays onto carbon cloth (CoNi@NCNTs/CC) is reported, as self-supported air electrodes for flexible zinc-air and aluminum-air batteries. CoNi@NCNTs/CC exhibits a low potential of 1.56 V at 10 mA cm−2 in OER, along with a half-wave potential of 0.82 V in ORR, which is attributed to abundant active sites including CoNi alloys with optimized adsorption energy, Co/Ni-Nx and N-doped CNTs. The well-designed nanotube array construction with substantial channels on carbon cloth facilitates the mass diffusion and electron delivery, and improves mechanical flexibility. Combining excellent activity and promising flexibility, CoNi@NCNTs/CC based liquid- and all-solid-state zinc-air batteries exhibit excellent charge/discharge capability and long-term stability. And the liquid- and all-solid-state aluminum-air batteries deliver promising discharge property with a high open circuit voltage as well as commendable flexibility. [Display omitted] •CoNi alloys derived N-doped carbon nanotube arrays on carbon cloth as freestanding flexible air electrodes.•The freestanding catalysts exhibit excellent bifunctional catalytic activity and stability for OER and ORR.•The air electrode enables excellent performance for liquid- and solid-state zinc-air and aluminum-air batteries.