Microflower Composites of Sulfide Nanosheets with 3D Boron Carbon–Nitrogen Compounds for High-Performance Microsupercapacitors

Boron carbon nitride (BCN) is very advantageous and attractive as an electrode material for supercapacitors, and 3D BCN has a higher ionic transport rate and superior electrochemical performance compared to 2D BCN. In this work, 3D BCN/SnS2 microflower composites were prepared by synthesizing precursors in a cost-effective way, followed by the uniform coating of SnS2 nanosheets on the surface of 3D BCN microspheres. The microflower composites exhibited superior electrochemical performance, achieving a specific capacitance of 729 F g–1 at 1 A g–1. The 3D BCN/SnS2 microflower composites were then applied as electrodes in microsupercapacitors (MSCs). It was found that the MSC had a good cycling stability; even after 10,000 cycles, it maintained a capacity retention rate of 87.7%. Additionally, the maximum power and energy densities of the MSC were 31.46 mW h cm–2 and 2525.32 mW cm–2, respectively. The above results indicate that 3D-BCN/SnS2 microflower composites have promising electrochemical properties and can be integrated into high-performance energy storage devices.