Interface-engineered molybdenum disulfide/porous graphene microfiber for high electrochemical energy storage

Fiber-shaped supercapacitors (F-SCs) have received great interests in future portable electronics and wearable industries due to their high charging capacity, exceptional weavability and long lifespan. However, the stacked micro/nano-structure and poor faradaic activity of fibrous electrode that severely restrict the ion dynamic transport and redox charge storage bring obstacles of low energy density and practical applications. Herein, we report a novel F-SCs electrode made of hierarchical-ordered molybdenum disulfide/porous graphene core-shell microfiber (MoS2/PGF). The MoS2/PGF exhibits highly conductive porous core, large electroactive shell, C-Mo chemical bonds bridge and interface-engineered structure, creating smooth channels and exposed surface for boosting ion kinetics and faradic charge transfer. Significantly, the MoS2/PGF presents high capacitance of 1093 mF cm−2 and steady cycling property in H3PO4 aqueous solution. Moreover, the MoS2/PGF assembled solid-state F-SCs show large energy density of 85.4 µWh cm−2, temperature-dependent stability and good bending capability. Given those outstanding advantages, the F-SCs can be integrated into flexible substrates to power wearable electronic devices, which will remarkably contribute to the development of new energy technology and carbon neutrality fields.