Wang Peng, Sun Fanghan, Xiong Shenglin, Zhang Zhengchunyu, Duan Bin, Zhang Chenghui, Feng Jinkui, Xi Baojuan
School of Chemistry and Chemical Engineering, State Key Laboratory of Crystal Materials, Shandong University, Ji Nan Shi, Jinan, 250100, P. R. China.
School of Control Science and Engineering, Shandong University, Jinan, 250061, P. R. China.
Angew Chem Int Ed Engl. 2022 Feb 7;61(7):e202116048. doi: 10.1002/anie.202116048. Epub 2021 Dec 23.
The practical application of lithium-sulfur batteries is still limited by the lithium polysulfides (LiPSs) shuttling effect on the S cathode and uncontrollable Li-dendrite growth on the Li anode. Herein, elaborately designed WSe flakelets immobilized on N-doped graphene (WSe /NG) with abundant active sites are employed to be a dual-functional host for satisfying both the S cathode and Li anode synchronously. On the S cathode, the WSe /NG with a strong interaction towards LiPSs can act as a redox accelerator to promote the bidirectional conversion of LiPSs. On the Li anode, the WSe /NG with excellent lithiophilic features can regulate the uniform Li plating/stripping to mitigate the growth of Li dendrite. Taking advantage of these merits, the assembled Li-S full batteries exhibit remarkable rate performance and stable cycling stability even at a higher sulfur loading of 10.5 mg cm with a negative to positive electrode capacity (N/P) ratio of 1.4 : 1.
锂硫电池的实际应用仍然受到多硫化锂(LiPSs)在硫阴极上的穿梭效应以及锂阳极上不可控的锂枝晶生长的限制。在此,精心设计的固定在具有丰富活性位点的氮掺杂石墨烯(WSe/NG)上的WSe薄片被用作双功能主体,以同时满足硫阴极和锂阳极的需求。在硫阴极上,与LiPSs具有强相互作用的WSe/NG可以作为氧化还原促进剂,促进LiPSs的双向转化。在锂阳极上,具有优异亲锂特性的WSe/NG可以调节锂的均匀沉积/剥离,以减轻锂枝晶的生长。利用这些优点,组装的锂硫全电池即使在硫负载量较高为10.5 mg cm且负正电极容量(N/P)比为1.4∶1的情况下,仍表现出卓越的倍率性能和稳定的循环稳定性。