Boosting the energy storage performance of MOF-derived Co 3 S 4 nanoarrays via sulfur vacancy and surface engineering.

Hierarchical Co 3 S 4 hollow nanosheet arrays are prepared through a MOF-engaged strategy, followed by room-temperature NaBH 4 treatment, resulting in simultaneous regulation of sulfur vacancies and surface morphology. The obtained electrode exhibits excellent electrochemical properties due to large active sites, fast charge diffusion and high electronic conductivity resulting from the hierarchical hollow structure and rich sulfur vacancies.