Scalable and ascendant synthesis of carbon cloth coated hierarchical core–shell CoMoS@Co(OH)2 for flexible and high-performance supercapacitors

Abstract

Herein, we propose a novel scalable and ascendant strategy to design a CoMoS@Co(OH)₂ core–shell architecture possessing a CoMoS nanorod “core” and Co(OH)₂ nanoflakes as the “shell” layer wall for flexible all-solid-state supercapacitor application. The surface architecture and material properties of the prepared material are characterized by electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Experimental analysis verifies that the nano-porous core–shell CoMoS@Co(OH)₂ architecture is strongly interconnected with the carbon cloth, ensuring sufficiently porous nanostructures. The core–shell CoMoS@Co(OH)₂ architecture exhibits a high capacitance of 1711 F g⁻¹ at a current density of 20 mA cm⁻², demonstrating a powerful synergistic effect efficiently using all of the desired functions of each material constituent. Finally, a flexible all-solid-state supercapacitor is fabricated using CoMoS@Co(OH)₂ and activated carbon as electrodes (CoMoS@Co(OH)₂//AC) and a polymer-based gel electrolyte. The fabricated flexible CoMoS@Co(OH)₂//AC asymmetric supercapacitor device delivers an energy density of 58.1 W h kg⁻¹ over the voltage range of 0–2 V with a capacitance retention of 91.47% after 8000 cycles. The illumination of a red light-emitting diode for more than 1.5 min is experimentally confirmed using a single solid-state CoMoS@Co(OH)₂//AC supercapacitor. These advantages indicate the considerable potential that the core–shell CoMoS@Co(OH)₂ architecture possesses for commercial applications.