Enhanced activity of Co-Mo-S catalysts towards hydrodesulfurization and hydrogen evolution reaction via NaBH₄...

Co-Mo-S based catalysts have promising applications in both the hydrogen evolution reaction (HER) and hydrodesulfurization (HDS). Herein, Co-Mo-S catalyst and Co-Mo-S catalyst with and without NaBH₄ modification have been successfully synthesized by a simple hydrothermal synthesis method. Co-Mo-S catalysts with NaBH₄ modification show better catalytic activity towards both HDS and the HER. The phase purity, morphology, crystal structures and electron valence distribution of the catalysts with and without NaBH₄ modification were studied by experimental characterizations and theoretical calculations. The catalysts without NaBH₄ modification are mostly 2H-MoS₂, while the catalysts without NaBH₄ modification have 1T-MoS₂, and 1T-MoS₂ is exposed to more active sites, which will be conducive to the results of HDS performance of the catalyst. DFT calculations investigated the required activation energies of 1T-MoS₂ and 2H-MoS₂ for HDS and HER, respectively. The activation energy required for both HDS and H₂ generation of 1T-MoS₂ is significantly lower than that for the 2H-MoS₂ structure.