Probing the electrochemical performance of monolayer armchair-GeS cathode for anion batteries: a DFT investigation

Anion batteries are emerging as a frontier research direction in novel energy storage systems due to their high energy density and superior safety profiles. This study employs first-principles calculations based on density functional theory to systematically investigate the potential of monolayer GeS as a cathode material for fluoride/chloride/bromide ion batteries. The work provides a comprehensive evaluation of thermodynamic stability, electronic structure, ion diffusion barriers, average open-circuit voltage and theoretical specific capacity. Computational results demonstrate that F^-, Cl^- and Br^- exhibit low adsorption energies (-2.04 eV, -0.63 eV and -1.54 eV) and low diffusion barriers (0.17 eV, 0.55 eV and 0.46 eV) within monolayer GeS, indicating robust spontaneous adsorption and efficient ionic mobility. Furthermore, monolayer GeS delivers high theoretical specific capacities of 618.7 mA h g^-1, 874.8 mA h g^-1 and 618.7 mA h g^-1 respectively, underscoring its considerable energy storage potential. These findings highlight the promise of monolayer GeS for next-generation anion battery cathodes and establish a reliable theoretical basis for the screening and design of electrode materials.