Microporous Architecture of Boron Carbon Nitride with Anomalous Performance for Supercapacitor and Oxygen Reduction Reaction

BCN nanostructures have emerged as exceptional candidates for energy storage and conversion owing to their outstanding stability and electrochemical performance. Introduction of microporous channels within these frameworks offers a direct route to boosting specific surface area and enhancing electrochemical activity. However, achieving uniform microporosity in BCN nanostructures remains a formidable challenge, limiting their full potential in advanced energy applications. Herein, the synthesis of microporous boron carbon nitride (ZBCN) is demonstrated through the simple encapsulation and carbonization of borane ammonia complex and sucrose in the nanochannels of the zeolitic template. ZBCN possesses randomly distributed micropores and a large surface area (1052 m² g⁻¹). The synthesized ZBCN exhibits an ultra-high specific capacitance of 311 F g⁻¹ (3-electrode) and 207 F g⁻¹ (2-electrode) at 0.5 A g⁻¹ with an excellent rate capability, cyclic stability, and ultrahigh energy density. Also, the electrocatalytic activity of ZBCN shows 5 times the activity than pristine nanoporous carbons at 0.5 A g⁻¹ in an alkaline medium. The structural, electronic, and catalytic properties derived through DFT calculations suggest that the B and N synergy in ZBCN created a balanced electronic environment that optimizes intermediate adsorption energies and minimizes energy barriers. The unusual electrocatalytic activity and the energy storage arise from the improved electrical contact, micropore active catalytic sites, and the synergetic effects between the boron and nitrogen on the graphenic domains. This excellent electrochemical performance and catalytic behavior anticipate the importance of designing micropore nanostructures with the potential for charge storage and ORR.