Yang Fangfang, Xie Zailai, Huang Xuke, Yin Xiangyang, Zhang Weifeng, Huang Yongkui, Zhang Daijun
Department of Environmental Science, Chongqing University, Chongqing 400044, China.
State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou 350002, China.
Phys Chem Chem Phys. 2023 Mar 29;25(13):9198-9207. doi: 10.1039/d2cp05761a.
Bi-based materials are promising electrocatalysts for CO reduction but one of the key technological hurdles is the design of stable, active and affordable Bi-based catalysts over a wide potential range. Herein, BiS/CNTs nanocomposites are constructed by anchoring bismuth sulfide (BiS) nanorods onto the multiwalled carbon nanotubes (CNTs) and utilizing them in electrocatalytic CO reduction. CNTs, as a support, not only guarantee the conductivity and dispersibility of BiS nanorods but also improve the electrolyte infiltration and optimize the electronic structure of the BiS. As expected, the BiS/CNTs nanocomposite exhibits a faradaic efficiency for HCOO (FE) of 99.3% with a current density of -20.3 mA cm at -0.91 V RHE. The FE is stably maintained at over > 91% in a wide potential window from -0.71 V to -1.31 V. Theoretical calculation analyses reveal that the strong interaction between BiS and CNTs is conductive to decreasing the energy barrier of *OCHO, stabilizing the intermediate *OCHO, and inhibiting the hydrogen evolution reaction. The current study provides an insightful understanding of the mechanism of the CO electroreduction reaction, and paves a new way for developing superior and affordable electrocatalysts.
铋基材料是用于CO还原的有前景的电催化剂，但关键的技术障碍之一是在宽电位范围内设计稳定、活性且经济实惠的铋基催化剂。在此，通过将硫化铋（BiS）纳米棒锚定在多壁碳纳米管（CNTs）上构建BiS/CNTs纳米复合材料，并将其用于电催化CO还原。作为载体的CNTs不仅保证了BiS纳米棒的导电性和分散性，还改善了电解质浸润并优化了BiS的电子结构。正如预期的那样，BiS/CNTs纳米复合材料在 -0.91 V RHE下，对HCOO的法拉第效率（FE）为99.3%，电流密度为-20.3 mA cm²。在从-0.71 V到-1.31 V的宽电位窗口中，FE稳定保持在>91%以上。理论计算分析表明，BiS与CNTs之间的强相互作用有助于降低OCHO的能垒，稳定中间体OCHO，并抑制析氢反应。当前的研究为理解CO电还原反应的机理提供了深刻见解，并为开发优异且经济实惠的电催化剂开辟了一条新途径。
