Crystalline-amorphous NiCo-LDH/NiCoOOH on bamboo-derived carbon for high-performance supercapacitors

Crystalline–amorphous interface engineering has emerged as a promising strategy for enhancing electrochemical performance in energy storage materials. Herein, we report a facile and green synthesis of a hierarchical NiCo-LDH/NiCoOOH heterostructure grown on bamboo-derived nitrogen-doped carbon (BNA) via in-situ partial oxidation using a K2S2O8/ammonia system at room temperature. The resulting composite features a three-dimensional nanoflower morphology composed of interconnected nanosheets, forming a crystalline–amorphous hybrid framework with abundant interfaces and hierarchical porosity. This architecture facilitates rapid ion/electron transport, enhances redox kinetics, and maintains mechanical integrity during cycling. As a result, the NiCo-LDH/BNA/NiCoOOH composite achieves a high specific capacitance of 1222.6 F g−1 at 1 A g−1 and good rate performance (848 F g−1 at 10 A g−1), with 91.6% capacity retention after 9000 cycles. When assembled into an asymmetric supercapacitor with BNA as the anode, the device delivers a high energy density of 84.34 Wh kg−1 at a power density of 850 W kg−1 and retains 51.22 Wh kg−1 at 8616 W kg−1. The assembled device also maintains 98.33% capacitance retention after 9000 cycles. This work highlights the potential of synergistic interface and structure engineering in developing high-performance, sustainable supercapacitor electrodes.