Predicting the Structure of MoS ₃ and Designing Transition-Metal-Doped Catalysts for Efficient CO ₂ Electroreduction

The development of efficient and highly selective catalysts for the electrochemical CO 2 reduction reaction (CO 2 RR) is crucial for achieving carbon neutrality and sustainable energy cycles. In this study, the stable structure of the MoS 3 monolayer was determined using the crystal structure prediction software CBD-GM. Owing to its distinct sulfur coordination environments and large dipole moment, MoS 3 serves as an ideal support for single-atom catalysts. By doping transition metals at specific sulfur sites (S 1 –S 3 ), we systematically screened a series of single-atom configurations for CO 2 activation. The results demonstrate that CO 2 molecules are effectively activated when Sc, Mn, Fe, Co, and Ni single atoms are doped at the S 2 site. Remarkably, Co S2 @MoS 3 and Ni S2 @MoS 3 are demonstrated as highly effective catalysts for selective CO 2 -to-CH 4 conversion, with low limiting potentials of −0.17 and −0.49 V, respectively. This study provides theoretical insights into the rational design of MoS 3 -based single-atom systems for efficient and selective CO 2 electroreduction.