酸性条件下での高耐久CO₂電解還元を実現（Researchers Achieve Durable Acidic CO2 Electroreduction to Formic Acid Through Metal-phase Protection Strategy）

2025-11-18 中国科学院（CAS）

＜関連情報＞

• https://english.cas.cn/newsroom/research_news/chem/202511/t20251118_1116511.shtml
• https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202517618

金属相保護によりBiの浸出を抑制し、耐久性のある酸性CO 2電気還元によるギ酸の生成を実現 Metal-Phase Protection Suppresses Bi Leaching for Durable Acidic CO2 Electroreduction to Formic Acid

Zijian Tan, Zhendong Luo, Zichao Wu, Dr. Xiaotong Li, Prof. Dr. Fang Lu, Prof. Dr. Xukai Zhou, Prof. Dr. Dunfeng Gao
Angewandte Chemie International Edition  Published: 10 November 2025
DOI:https://doi.org/10.1002/anie.202517618

Graphical Abstract

A highly durable BiCu bimetallic catalyst for acidic CO₂ electroreduction to formic acid is developed via a metal phase-protection strategy. The interphase interaction between CuBi₂O₄ and Bi₂O₃ results in compressive strain and lattice contraction in the Bi₂O₃ phase, effectively strengthening the Bi─O bonds. This structural modulation suppresses Bi leaching during electrochemical reconstruction and preserves more Bi₂O₂CO₃ active phases, thereby improving the long-term durability (500 h), outperforming the common Bi₂O₃ catalyst.

Abstract

The electrocatalytic CO₂ reduction reaction (CO₂RR) in acidic electrolyte mitigates salt precipitation and carbon loss compared to that in alkaline and neutral electrolytes. However, the harsh acidic environments cause metal leaching and catalyst degradation, thereby impairing activity and long-term durability. Here we propose a metal-phase protection strategy that enables in situ formation of a BiCu catalyst (Bi_0.31Cu₁) with impressive durability for acidic CO₂RR to formic acid (HCOOH). The compressive strain of the Bi₂O₃ phase in Bi_0.31Cu₁, induced by its interaction with the CuBi₂O₄ phase, enhances Bi─O bond strength and mitigates Bi leaching during in situ electrochemical reconstruction, thus delivering highly desired activity and durability. The Bi_0.31Cu₁ catalyst achieves a HCOOH Faradaic efficiency (FE) of above 90% in a wide current density range from 200 to 650 mA cm⁻². In a 0.5 M KCl electrolyte with pH 2, the Bi_0.31Cu₁ catalyst can continuously produce HCOOH with a FE of around 90% at 200 mA cm⁻² for 500 h. This work showcases the great promise of the metal-phase protection strategy for minimizing metal leaching and improving the long-term durability of acidic CO₂ electrolysis.