Carbide-derived carbon by room temperature chemical etching of MAX phase for supercapacitor application

Porous carbons have attracted substantial interest within the realm of energy storage applications. However, their traditional production methods often involve the use of elevated temperatures. In this study, we introduce a simple technique to transform titanium silicon carbide (Ti3SiC2) MAX phases into porous carbons, known as carbide-derived carbons (CDCs), at room temperature by selective etching of the metal atoms (Ti and Si). We investigate how temperature affects the activation of CDCs so formed with potassium hydroxide to enhance their electrochemical properties. Our results unveil the remarkable potential of CDCs activated at 700 °C, demonstrating superior electrochemical performance with a specific capacitance of 198 F g−1 at a scan rate of 20 mV s−1 in a three-electrode configuration. The symmetric supercapacitor based on CDC-700 maintains a respectable specific capacitance of 98 F g−1 at 1 A g−1 and an energy density of 13.7 Wh kg−1 at a power density of 1 kW kg−1. This cost-effective approach offers a pathway for large-scale CDC production, with excellent specific supercapacitor characteristics, promising advancements in energy storage technology.