Rapid and precise fabrication of a three-dimensional, high-capacity, asymmetric micro-supercapacitor utilizing mortise-and-tenon joint construction

Abstract

3D asymmetric micro-supercapacitors (AMSCs) possess considerable significance for portable, flexible, and integrated electronic devices. Here, we synthesize 3D ice-like MnO₂ and nitrogen-doped carbon nanotube (N-CNT) arrays on a 3D wood-derived carbon (WDC) scaffold, respectively. The MnO₂–WDC and N-CNT–WDC microelectrodes, characterized by an interlocking mortise-and-tenon structure, are fabricated using laser technology, facilitating the straightforward and rapid assembly of 3D AMSCs. The engineered 3D AMSC exhibits a specific capacitance of 108 F cm⁻³ at a volume current density of 50 mA cm⁻³ and demonstrates excellent stability, retaining 90% of its initial performance after 10 000 galvanostatic charge–discharge cycles at a volume current density of 1000 mA cm⁻³. The 3D AMSCs achieves a volume energy density of 38 mWh cm⁻³ and a volume power density of 56 mW cm⁻³ at a volume current density of 70 mA cm⁻³. This study presents novel methodologies for the rapid and precise construction of 3D AMSC utilizing a mortise-and-tenon structure.