Synthesis of h-BN/CNTs nanocomposites for good cycling stability supercapacitors

The practical application of aqueous supercapacitors is constrained by the balance between cycle life and power characteristics. This study develops a composite electrode based on hexagonal boron nitride/carbon nanotubes (h-BN/CNTs), featuring fabrication processes through thermal annealing and electrostatic assembly. The material ingeniously combines the chemical inertness and structural stability of h-BN with the conductive network of CNTs, successfully constructing an electrode with highly stable mechanical and electrochemical interfaces. The assembled symmetric supercapacitor demonstrates excellent long-term operational reliability, maintaining over 90% stability after 10,000 charge-discharge cycles while exhibiting outstanding rate performance. The core value of this work lies in its application to h-BN platforms for high-power, high-frequency optical devices, successfully transforming it into a high-performance electrochemical energy storage component. The material has a high power density of 600 W/kg and a fairly good energy density of 13.6 Wh/kg in the symmetric two-electrode test. This device construction strategy based on a unified core material system creates compatibility advantages for material substrate and process-level integration with high-power optical devices, providing a material foundation for developing next-generation optoelectronic integrated systems. • h-BN was synthesized by the method of thermal annealing, and elemental composition, crystal structure as well as morphology are characterized. • CNTs was recombined with h-BN to enhance electrical conductivity of material. • Enhancement of electrical conductivity was confined by EIS, and specific capacitance was increased by this way.