Enhancing Cycling Stability of Tungsten Oxide Supercapacitor Electrodes via a Boron Cluster-Based Molecular Cross-Linking Approach

We report our discovery of utilizing perhydroxylated dodecaborate clusters ([B12(OH)12]2−) as a molecular cross-linker to generate a hybrid tungsten oxide material. The reaction of [NnBu4]2[B12(OH)12] with WCl6, followed by subsequent annealing of the product at 500 °C in air successfully produces a tungsten oxide material cross-linked with B12-based clusters. The comprehensive structural study of the produced hybrid material confirms a cross-linked network of intact boron-rich clusters and tungsten oxides. We further demonstrate how these robust B12-based clusters in the resulting hybrid tungsten oxide material can effectively preserve the specific capacitance up to 4000 cycles and reduce the charge transfer resistance as well as the response time compared to that of pristine tungsten oxide. Ultimately, this work highlights a promising capability of boron-rich clusters in hybrid metal oxides to obtain fast and stable supercapacitors with high capacitance.