Crystal-Collapse-Induced Synthesis of High-Capacitance LaCoO_x/Co-Doped Carbon-Based Supercapacitors

The development of high-performance, reproducible carbon (C)-based supercapacitors remains a significant challenge because of limited specific capacitance. Herein, we present a novel strategy for fabricating LaCoO_x and cobalt (Co)-doped nanoporous C (LaCoO_x/Co@ZNC) through the carbonization of Co/Zn-zeolitic imidazolate framework (ZIF) crystals derived from a PVP-Co/Zn/La precursor. The unique ZIF structure effectively disrupted the graphitic C framework, preserved the Co active sites, and enhanced the electrical conductivity. The synergistic interaction between pyridinic nitrogen and Co ions further promoted redox reactions. In addition, the formation of a hierarchical pore structure through zinc sublimation facilitated electrolyte diffusion. The resulting LaCoO_x/Co@ZNC exhibited exceptional electrochemical performance, delivering a remarkable specific capacitance of 2,789 F/g at 1 A/g and outstanding cycling stability with 92% capacitance retention after 3,750 cycles. Our findings provide the basis for a promising approach to advancing C-based energy storage technologies.