All-solid-state flexible micro-supercapacitors with enhanced electrochemical performance obtained by hybridizing mxene with butterfly graphite

Abstract

Abstract All-solid-state flexible micro-supercapacitors (MSCs) have the advantages of large energy storage capacity, small size, and good flexibility, which can be used as micro power sources. A 2D titanium carbide (MXene) has metallic conductivity, good hydrophility, and excellent processing properties, showing its great potential in flexible MSCs. However, the self-packing of MXene sheets hinders charge transfer and ion transport, limiting its electrochemical capacity. Herein, MSCs were prepared from a composite material of butterfly-like graphite (BTG) and MXene. BTG was inserted into the MXene layer to prevent its overs tacking, which promotes the diffusion of electrolytes and improves the electrochemical capacity of MSCs. As a result, MXene/BTG MSCs exhibit a large capacitance of 177.9 mF cm −2 at 5 mV s −1 . In addition, the specific capacitance retention of MXene/BTG-30% MSCs can reach 80.4% in 0.1 -1 mA cm −2 .