Liu Fuming, Luo Mei, Wang Keliang, Li Ziwei, Liu Fei, Li Min
Guizhou Provincial Key Laboratory of Green Chemical and Clean Energy Technology, School of Chemistry and Chemical Engineering, Guizhou University, Guiyang 550025, China.
School of Chemical and Materials Engineering, Liupanshui Normal University, Liupanshui 553004, China.
J Colloid Interface Sci. 2025 Jan 15;678(Pt A):311-321. doi: 10.1016/j.jcis.2024.08.163. Epub 2024 Aug 22.
Electrochemical CO reduction reaction (CORR) is one of the most attractive measures to achieve the carbon neutral goal by converting CO into high-value chemicals such as formate. Si in Bi silicates is promising to enhance CO adsorption and activation due to its strong oxygenophilicity. Whereas, its role in boosting CORR via the cheap Bi-based catalysts is still not clear. Herein, we design CNT@Bi silicates catalyst, demonstrating the highest FE of 96.3 % at -0.9 V vs. reversible hydrogen electrode with good stability. Through X-ray photoelectron spectroscopy (XPS), in-situ Attenuated Total Reflectance-Fourier Transform Infrared (In-situ ATR-SEIRAS) experiments, and Density Functional Theory (DFT) calculations, the role of Si in Bi silicates was unveiled: tuning the electronic structure of Bi, weakening the Bi-O bond, and strengthening electron transfer from Bi to CO, thereby promoting the generation of CO* and *OCHO intermediates. Additionally, carbon nanotubes (CNTs) promote not only the conductivity but also the generation of abundant oxygen vacancies in CNT@Bi silicates evidenced by the electron transfer from CNT to Bi silicates from XPS results. Further, the CNT@Bi silicates endows it with the highest electrochemical activation area. These findings suggest the effectiveness of Si in Bi silicates and structure tuning to design highly selective CORR catalyst for HCOOH production.
电化学CO还原反应（CORR）是通过将CO转化为高价值化学品（如甲酸盐）来实现碳中性目标的最具吸引力的措施之一。铋硅酸盐中的硅因其强亲氧性而有望增强CO的吸附和活化。然而，其在通过廉价的铋基催化剂促进CORR中的作用仍不清楚。在此，我们设计了CNT@铋硅酸盐催化剂，在相对于可逆氢电极-0.9V时显示出高达96.3%的最高法拉第效率，且具有良好的稳定性。通过X射线光电子能谱（XPS）、原位衰减全反射傅里叶变换红外光谱（原位ATR-SEIRAS）实验和密度泛函理论（DFT）计算，揭示了硅在铋硅酸盐中的作用：调节铋的电子结构，削弱Bi-O键，并加强从铋到CO的电子转移，从而促进CO和OCHO中间体的生成。此外，碳纳米管（CNTs）不仅促进了导电性，还促进了CNT@铋硅酸盐中大量氧空位的产生，XPS结果证明了从CNT到铋硅酸盐的电子转移。此外，CNT@铋硅酸盐赋予其最高的电化学活化面积。这些发现表明了铋硅酸盐中硅的有效性以及结构调控对设计用于生产HCOOH的高选择性CORR催化剂的作用。
