Turn "Waste" Into Wealth: MoO2 @coal Gangue Electrocatalyst with Amorphous/Crystalline Heterostructure for Efficient Li-O2 Batteries

Small. 2023 Jul;19(27):e2208145. doi: 10.1002/smll.202208145. Epub 2023 Mar 25.

Abstract

Unreasonable accumulation of coal gangue in mining area has become the major source of global pollution. Probing the high-valued utilization of coal gangue has become a key approach to address the problem. Herein, a promising catalyst of MoO2 @coal gangue with amorphous/crystalline heterostructure derived from mine solid waste, which acts as an efficient cathode for Li-O2 batteries is first reported. Impressively, the as-prepared catalyst exhibits a favorable initial discharge capacity of 9748 mAh g-1 and promising long-term cyclic stability over 2200 h. Experimental results coupled with density functional theory (DFT) analysis reveal that the synergistic interaction between high-activity MoO2 and stable SiO2 , unique amorphous/crystalline heterostructure and the modified interfacial adsorption of LiO2 intermediate are critical factors in promoting the electrochemical performance. This work provides a new insight to design marked electrocatalysts by mine solid waste for Li-O2 batteries.

Keywords: Li-O 2 batteries; amorphous/crystalline heterostructures; bifunctional electrocatalysts; electronic structure regulation; mining solid waste.