A B,N co-doped carbon nanotube array with anchored MnO2 nanosheets as a flexible cathode for aqueous zinc-ion batteries

For rechargeable aqueous zinc-ion batteries (ZIBs), the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great promise in addressing the issue of electrical conductivity and structural stability in the electrode materials during electrochemical cycling. We report the production of a novel flexible electrode material, by anchoring MnO 2 nanosheets on a B,N co-doped carbon nanotube array (BNCNTs) grown on carbon cloth (BNCNTs@MnO 2 ), which was fabricated by in-situ pyrolysis and hydrothermal growth. The generated BNCNTs were strongly bonded to the surface of the carbon fibers in the carbon cloth which provides both excellent electron transport and ion diffusion, and improves the stability and durability of the cathode. Importantly, the BNCNTs offer more active sites for the hydrothermal growth of MnO 2 , ensuring a uniform distribution. Electrochemical tests show that BNCNTs@MnO 2 delivers a high specific capacity of 310.7 mAh g −1 at 0.1 A g −1 , along with excellent rate capability and outstanding cycling stability, with a 79.7% capacity retention after 8000 cycles at 3 A g −1 .