Rationally constructing the electrode with the hierarchical structure, different components, and the flexibility is a promising approach to further improve the electrochemical properties and meet the demand for flexible electronic devices. In this paper, for the first time, hafnium carbide nanowires (HfC_NWs) networks, with the metrics of large specific surface area, excellent conductivity, and chemical/physical stability, are served as nanoscale conductive skeletons on carbon cloth (CC) for supporting the porous NiCo₂O₄ nanosheets (NSs). Benefiting from the structural advantages, the as-formed free-standing core-shell NiCo₂O_4NSs@HfC_NWs/CC exhibits a high specific capacitance of 2102 F g^-1 at a current density of 1 A g^-1, good rate capability (85% capacitance retention at 20 A g^-1) and outstanding cycling stability (98% capacitance retention after 5000 cycles at 10 A g^-1). Additionally, assembled with the NiCo₂O_4NSs@HfC_NWs/CC and activated carbon (AC)/CC, the flexible solid-state hybrid supercapacitor displays a high energy density of 53 Wh kg^-1 at a power density of 800 W kg^-1 and excellent performance stability with good flexibility. More impressively, our work could not only further widen the application of HfC_NWs, but also put forward the new thinking of rational construction of high-performance flexible supercapacitors.

合理地构造具有分层结构，不同组件和柔性的电极是一种有前途的方法，可以进一步提高电化学性能并满足对柔性电子器件的需求。本文首次将具有较大比表面积，出色的电导率和化学/物理稳定性等指标的碳化_ha纳米线（HfC _NWs）网络用作碳布（CC）上的纳米级导电骨架，以进行支撑多孔NiCo ₂ O ₄纳米片（NSs）。从结构上的优点中受益，这样形成的自由站立的核壳镍钴₂ ö _4NSs @HfC_纳米线/ CC在1 A g ^-1的电流密度下表现出2102 F g ^-1的高比电容，良好的倍率能力（20 A g ^-1时的电容保持率为85％）和出色的循环稳定性（5000后的电容保持率为98％）在10 A g ^-1下循环）。另外，组装有镍钴₂ ö _4NSs @HfC_纳米线/ CC和活性炭（AC）/ CC，柔性的固态混合超级电容器显示器53瓦公斤的高能量密度^-1在800瓦kg的功率密度^{- 1}，优异的性能稳定性和良好的柔韧性。更令人印象深刻的是，我们的工作不仅可以进一步扩大HfC _NW的应用，也提出了合理构建高性能柔性超级电容器的新思路。