College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, PR China.
College of Water Sciences, Beijing Normal University, Beijing, 100875, PR China.
Chemosphere. 2022 Aug;301:134704. doi: 10.1016/j.chemosphere.2022.134704. Epub 2022 Apr 26.
In this work, a novel catalytic cathode of polyethyleneimine (PEI)-Sn/Cu foam with dendritic structure was prepared by electrodeposition and impregnation. It was used in the electrocatalytic reduction of CO to HCOOH, and its performance in this process was evaluated. At -0.97 V vs. RHE, the faradaic efficiency and current density reached 92.3% and 57.1 mA cm, respectively, in a 0.5 M KHCO electrolyte. The HCOOH production rate reached 890.4 μmol h cm, which exceeds those for most reported Sn catalysts. Density functional theory calculations showed that use of Sn/Cu foam is more conducive to HCOOH formation than use of Cu or Sn alone, and *OCHO is the main intermediate in HCOOH formation. The results of OH adsorption experiments confirmed that the introduction of PEI enhanced the catalytic capacity of the Sn/Cu foam, stabilized CO· intermediates, and promoted HCOOH generation. These results will provide an attractive strategy for developing efficient catalysts with excellent activities and stabilities for CO electroreduction.
在这项工作中，通过电沉积和浸渍法制备了具有树枝状结构的新型聚乙烯亚胺（PEI）-Sn/Cu 泡沫催化阴极。它被用于 CO 电化学催化还原为 HCOOH，并评估了其在该过程中的性能。在 0.5 M KHCO3 电解质中，-0.97 V 对 RHE 的条件下，法拉第效率和电流密度分别达到 92.3%和 57.1 mA cm-2。HCOOH 的生成速率达到 890.4 μmol h cm-2，超过了大多数报道的 Sn 催化剂。密度泛函理论计算表明，与单独使用 Cu 或 Sn 相比，使用 Sn/Cu 泡沫更有利于 HCOOH 的形成，并且*OCHO 是 HCOOH 形成的主要中间产物。OH 吸附实验的结果证实，PEI 的引入增强了 Sn/Cu 泡沫的催化能力，稳定了 CO·中间体，并促进了 HCOOH 的生成。这些结果将为开发具有优异活性和稳定性的 CO 电催化还原高效催化剂提供有吸引力的策略。
