Two-dimensional transition metal carbide and nitride are promising energy storage materials. However, the aggregation and rearrangement of two-dimensional nanosheets limit their electrochemical performance. In this paper, a novel hierarchical porous “skin/skeleton”-like MXene/biomass derived carbon fibers (MXene/CF) heterostructure is prepared by one-step pyrolysis, which efficiently weakens the stacking of MXene nanosheets. Moreover, MXene/CF has a well-defined hierarchical porous structure, thereby facilitating electrolyte penetration and providing efficient and stable channels for rapid diffusion/transfer of ions to the electrode and producing functional MXene-based electrodes. When MXene/CF heterostructure is applied as a self-supporting electrode for supercapacitors, the electrode has high volumetric capacitance of 7.14 F cm^-3, good rate characteristics (63.9% from 0.5 to 100 A g^-1), and excellent cyclic stability (99.8% after 5000 cycles). In addition, all solid-state symmetric supercapacitors based on MXene/CF electrodes are also assembled, which not only exhibits high capacitance and rate performance, but also has good flexibility and long durability. The device still maintains structural integrity and steady capacitance even after 2,500 cycles at different bending angles. This work is expecting to guide the design of the next generation of flexible, portable and highly integrated supercapacitors with high capacity and rate performance to further meet the requirements of sustainable development.

二维过渡金属碳化物和氮化物是有前途的储能材料。然而，二维纳米片的聚集和重排限制了它们的电化学性能。在本文中，通过一步热解制备了一种新型的分层多孔“皮肤/骨架”样MXene /生物质衍生碳纤维（MXene / CF）异质结构，有效地削弱了MXene纳米片的堆叠。此外，MXene / CF具有定义明确的分层多孔结构，从而促进了电解质的渗透，并提供了有效而稳定的通道，可将离子快速扩散/转移到电极上并生产功能性的MXene基电极。当将MXene / CF异质结构用作超级电容器的自支撑电极时，该电极具有7.14 F cm的高体积电容^-3，良好的速率特性（0.5至100A g ^-1为63.9％）和优异的循环稳定性（5000次循环后为99.8％）。另外，还组装了所有基于MXene / CF电极的固态对称超级电容器，不仅具有高电容和倍率性能，而且具有良好的柔韧性和长寿命。即使在不同的弯曲角度下经过2500次循环后，该器件仍可保持结构完整性和稳定的电容。这项工作有望指导具有高容量和高倍率性能的下一代柔性，便携式和高度集成的超级电容器的设计，以进一步满足可持续发展的要求。