Valence-engineering modulation of MoS clusters for enhancing biocatalytic activity.

Earth-abundant MoS with the advantages of a stable structure, tunable bandgap, and easy shear has great potential for applications in the fields of catalysis, biomedicine, and so on. However, the biocatalytic activity of MoS remains little investigated and is insufficient for biomedical applications. In this work, we develop ultra-small and water-soluble MoS clusters with superior antioxidant activity and enzyme-like activity valence-engineering modulation with Ce doping. Compared with pure, Re-, Tl-, and Nd-MoS clusters, Ce-MoS clusters exhibit about 1.7-fold enhanced antioxidant activity. Moreover, superoxide dismutase (SOD)-like activity of Ce-MoS clusters is about 30-fold higher than that of MoS clusters. In addition, the Ce-MoS clusters are evidenced to possess ultra-high clearance performance for reactive oxygen species and reactive nitrogen radicals (RONS), especially ˙OH and O˙. The comprehensive analyses of valence evolution and the energy level structure indicate that the enhanced biocatalytic activity is attributed to the synergistic effect of valence engineering of Mo/Mo and energy-level engineering in MoS clusters Ce doping. This work provides a universal approach to improve the biocatalytic activity of MoS clusters valence engineering modulation, which exhibits great potential in the field of biomedical application, especially inflammatory diseases.