Although recently developed hybrid zinc (Zn) batteries integrate the benefits of both alkaline Zn and Zn-air batteries, the kinetics of the electrocatalytic oxygen reaction and mass transfer of the electrolyte, which are limited by the mismatched and disordered multiphase reaction's interfacial transfer channels, considerably inhibit the performance of hybrid Zn batteries. In this work, novel, continuously oriented three-phase interfacial channels at the cathode derived from the natural structure of pine wood are developed to address these challenges. A pine wood chip is carbonized and asymmetrically loaded with a hydrophilic active material to achieve the creation of a wood-derived cathode that integrates the active material, current collector, and continuously oriented three-phase reaction interfacial channels, which allows the reaction dynamics to be accelerated. Consequently, the assembled quasi-solid-state hybrid battery performs an extra charge-discharge process beyond that performed by a typical nickel (Ni)-Zn battery, resulting in a wide operating voltage range of 0.6-2.0 V and a superior specific capacity of 656.5 mAh g-1 , in addition to an excellent energy density (644.7 Wh kg-1 ) and good durability. The ≈370% capacity improvement relative to the Ni-Zn battery alone makes the hybrid battery one of the best-performing alkaline Zn batteries.
Keywords: alkaline zinc batteries; asymmetric wettability; quasi-solid-state; three-phase interfacial channels; wood.
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