Biowaste Orange Peel‐Derived Mesoporous Carbon as a Cost‐Effective Anode Material with Ultra‐Stable Cyclability for Potassium‐Ion Batteries

Abstract

AbstractPotassium‐ion batteries (PIBs) are promising alternative to Lithium‐ion batteries (LIBs) owing to their economic merits. However, the PIBs have not met suitable anode materials comparable to graphite in LIBs. We synthesised an orange peel‐derived mesoporous carbon (OPDMC) as a potential anode material for high performance PIBs via facile one‐step carbonisation with self‐activation from waste orange peel. The OPDMC‐1000, which were carbonised at 1000 °C, exhibited impressive initial discharge/charge capacities of 408/224 mAh g−1 at 30 mA g−1 and retained the reversible capacity of 208.57 mAh g−1 over 100 cycles. Even after 2000 and 3000 cycles at specific currents of 200 and 500 mA g−1, it maintained the reversible capacities of 150.37 and 112 mAh g−1, respectively. A full cell employing the OPDMC exhibited an initial reversible discharge capacity of 185.32 mAh g−1 at 50 mA g−1 with capacity retention of 71.60 % after 50 cycles, indicating its practical applicability.