Spin polarization induced by atomic strain of MBene promotes the ·O2- production for groundwater disinfection

Nat Commun. 2025 Jan 2;16(1):197. doi: 10.1038/s41467-024-55626-8.

Abstract

Superbugs in groundwater are posing severe health risks through waterborne pathways. An emerging approach for green disinfection lies at photocatalysis, which levers the locally generated superoxide radical (·O2-) for neutralization. However, the spin-forbidden feature of O2 hinders the photocatalytic generation of active ·O2-, and thus greatly limited the disinfection efficiency, especially for real groundwater with a low dissolved oxygen (DO) concentration. Herein, we report a class of strained Mo4/3B2-xTz MBene (MB) with enhanced adsorption/activation of molecular O2 for photocatalytic disinfection, and find the strain induced spin polarization of In2S3/Mo4/3B2-xTz (IS/MB) can facilitate the spin-orbit hybridization of Mo sites and O2 to overcome the spin-forbidden of O2, which results in a 16.59-fold increase in ·O2- photocatalytic production in low DO condition (2.46 mg L-1). In particular, we demonstrate an In2S3/Mo4/3B2-xTz (50 mg)-based continuous-flow-disinfection system stably operates over 62 h and collects 37.2 L bacteria-free groundwater, which represents state-of-the-art photodisinfection materials for groundwater disinfection. Most importantly, the disinfection capacity of the continuous-flow-disinfection system is 25 times higher than that of commercial sodium hypochlorite (NaOCl), suggesting the practical potential for groundwater purification.