Construction of Interlayer 2D Conductive Channels in a Ti3C2Tx/Metal-Organic Framework Composite Toward Enhanced Flexible Supercapacitor Performance

Abstract

MXenes and their composites have been extensively investigated as electrode materials for supercapacitors, benefiting from the excellent electrical conductivity, abundant surface-active groups, and high flexibility of two-dimensional (2D) MXene nanosheets. However, from the severe self-stacking of MXene sheets and the presence of inactive surface terminations impede their further development in this field. Moreover, conventional MXene composites generally suffer from inefficient charge transport because traditional conductive particulate spacers create only point-contact pathways rather than continuous conductive channels. To address these issues, a strategy is proposed to construct continuous interlayer 2D conductive channels integrated with a gel-state long-range conductive network in a Ti₃C₂T_x/π-d conjugated metal-organic framework (MOF) composite. In this architecture, spontaneous interactions between surface functional groups form a gel-state conductive network with abundant voids, enabling efficient electron and ion transport through continuous interlayer 2D channels. Subsequent thermal treatment induces nitrogen doping from the MOF into the composite, creating additional electrochemically active sites, thereby realizing secondary electrochemical enhancement. As a result, the composite electrode exhibits markedly improved power and energy densities compared with bare Ti₃C₂T_x electrode. This work provides an effective interfacial engineering strategy for the design of high-performance pseudocapacitive electrode materials.