Li Xuejin, Tang Yongchao, Han Cuiping, Wei Zhiquan, Fan Haodong, Lv Haiming, Cai Tonghui, Cui Yongpeng, Xing Wei, Yan Zifeng, Zhi Chunyi, Li Hongfei
School of Materials Science and Engineering, State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, Shandong 266580, PR China.
Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, PR China.
ACS Nano. 2023 Mar 14;17(5):5083-5094. doi: 10.1021/acsnano.3c00242. Epub 2023 Feb 28.
High-potential Mn/Mn redox couple (>1.3 V vs SHE) in a static battery system is rarely reported due to the shuttle and disproportionation of Mn in aqueous solutions. Herein, based on reversible stripping/plating of the Sn anode and stabilized Mn/Mn redox couple in the cathode, an aqueous Sn-Mn full battery is established in acidic electrolytes. Sn anode exhibits high deposition efficiency, low polarization, and excellent stability in acidic electrolytes. With the help of H and a complexing agent, a reversible conversion between Mn and Mn ions takes place on the graphite surface. Pyrophosphate ligand is initially employed to form a protective layer through a complexation process with Sn on the electrode surface, effectively preventing Mn from disproportionation and hindering the uncontrollable diffusion of Mn to electrolytes. Benefiting from the rational design, the full battery delivers satisfied electrochemical performance including a large capacity (0.45 mAh cm at 5 mA cm), high discharge plateau voltage (>1.6 V), excellent rate capability (58% retention from 5 to 30 mA cm), and superior cycling stability (no decay after 30 000 cycles). The battery design strategy realizes a robustly stable Mn/Mn redox reaction, which broadens research into ultrafast acidic battery systems.
由于锰在水溶液中的穿梭和歧化作用，静态电池系统中高电位的锰/锰氧化还原对（相对于标准氢电极>1.3 V）鲜有报道。在此，基于锡阳极的可逆剥离/镀覆以及阴极中稳定的锰/锰氧化还原对，在酸性电解质中建立了水系锡-锰全电池。锡阳极在酸性电解质中表现出高沉积效率、低极化和优异的稳定性。在氢离子和络合剂的帮助下，锰与锰离子在石墨表面发生可逆转化。最初采用焦磷酸盐配体通过与电极表面的锡络合形成保护层，有效防止锰的歧化，并阻碍锰向电解质的不可控扩散。得益于合理的设计，全电池具有令人满意的电化学性能，包括大容量（在5 mA cm²时为0.45 mAh cm²）、高放电平台电压（>1.6 V）、优异的倍率性能（从5到30 mA cm²保持58%）和卓越的循环稳定性（30000次循环后无衰减）。该电池设计策略实现了稳健稳定的锰/锰氧化还原反应，拓宽了对超快酸性电池系统的研究。
