Enhancing CO hydrogenation to methanol the synergistic effect of MoS interlayer spacing and sulfur vacancies

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024-08, Vol.12 (31), p.217-2114
• Main Authors: Qin, Langlang, Gao, Yunfei, Han, Caiyun, Zhu, Minghui, Wang, Shuang
• Format: Article
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d4ta02861a

The hydrogenation of carbon dioxide (CO 2 ) to methanol is an important reaction to convert CO 2 into valuable products and reduce carbon emission. MoS 2 is an effective catalyst for CO 2 hydrogenation, but the synergistic effects of interlayer spacing expansion and surface sulfur vacancy strengthening have not been studied systematically. Here, this work reports hydrazine hydrate as an effective reducing agent for MoS 2 . The reducing agent can not only expand the interlayer spacing of MoS 2 , but also increase the concentration of sulfur vacancies through a simple treatment. More importantly, the synergistic effect between the interlayer spacing and sulfur vacancies of MoS 2 significantly increases the methanol space-time yield (STY). At 220 °C, 4 MPa, and 8000 mL g cat −1 h −1 , the MoS 2 -N 2 H 4 -4 catalyst exhibits 76.8% methanol selectively, 5.52% CO 2 conversion, and a high methanol STY of up to 0.1214 g g cat −1 h −1 and lasts for at least 200 h. The structure-performance relationship was further studied using physio-chemical characterization and DFT. These results provide valuable insights into the development of highly efficient MoS 2 catalysts for CO 2 hydrogenation. CO 2 is reduced to methanol via the synergistic effect of expansion of the interlayer spacing and sulfur vacancies of MoS 2 .