Jiang Xinyuan, Wu Yuchao, Lv Zengxiang, Yang Guang, Wang Mengyao, Zhou Qiuping, Shen Yunjun, Chen Ming, Ni Lubin, Diao Guowang
School of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou, 225002, Jiangsu, People's Republic of China.
Key Laboratory of Chemistry and Engineering of Forest Products, State Ethnic Affairs Commission, Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Guangxi Collaborative Innovation Center for Chemistry and Engineering of Forest Products, Guangxi Minzu University, Nanning, 530006, China.
Chemistry. 2024 Oct 17;30(58):e202402706. doi: 10.1002/chem.202402706. Epub 2024 Oct 2.
Recently, research on polyoxometalates (POMs) has gained significant momentum. Owing to their properties as electronic sponges, POMs catalyst harbor substantial potential in lithium-sulfur battery research. However, POMs undergo a transformation into reduced heteropoly blue (HPB) during electrochemical reactions, which then dissolve into the electrolyte, resulting in catalyst loss. In this research, we amalgamated 18-crown-6 (CR6) with KPWO, (KPW), synthesized a novel POM-based supramolecular compound, and integrated it with graphene oxide (GO) to fabricate a multi-functional composite polypropylene (PP) separator KPW-CR6/GO/PP. The crown ether array was employed to immobilize POM and construct ion transport channels, thereby enhancing the Li migration rate and capturing polysulfides. Subsequently, leveraging the stable structure and redox properties of POM, the polysulfide is catalyzed to transform and inhibit the shuttle effect, thereby protecting the Li anode. The lithium-sulfur batteries with the Crown ether-POM supramolecular compound separators, exhibit enhanced capacity and stability (1073.3 mAh g at 1.0 C, and 81.5 % retention rate after 250 cycles). The battery (S loading: 3.2 mg cm) presents an initial specific discharge capacity of 543.4 mAh g at 0.5 C, with 89.8 % of the capacity retained after 160 cycles. This underlines the practical application potential of Crown ether-POM supramolecular materials in Li-S batteries.
最近，对多金属氧酸盐（POMs）的研究取得了显著进展。由于其作为电子海绵的特性，POMs催化剂在锂硫电池研究中具有巨大潜力。然而，POMs在电化学反应过程中会转变为还原态杂多蓝（HPB），然后溶解到电解质中，导致催化剂损失。在本研究中，我们将18-冠-6（CR6）与KPWO（KPW）合并，合成了一种新型的基于POM的超分子化合物，并将其与氧化石墨烯（GO）整合，制备了一种多功能复合聚丙烯（PP）隔膜KPW-CR6/GO/PP。冠醚阵列用于固定POM并构建离子传输通道，从而提高Li迁移速率并捕获多硫化物。随后，利用POM的稳定结构和氧化还原特性，催化多硫化物转化并抑制穿梭效应，从而保护锂负极。具有冠醚-POM超分子化合物隔膜的锂硫电池表现出增强的容量和稳定性（在1.0 C下为1073.3 mAh g，250次循环后保留率为81.5%）。该电池（硫负载量：3.2 mg cm）在0.5 C下的初始比放电容量为543.4 mAh g，160次循环后容量保留89.8%。这突出了冠醚-POM超分子材料在锂硫电池中的实际应用潜力。
