Ultrathin Palladium-loaded Cuprous oxide stabilises Copper(I) to facilitate electrochemical carbon dioxide reduction reaction

Xiaoye Du; Jaehyun Kim; Bo Gao; Dan Qian; Chunhui Xiao; Shujiang Ding; Zhongxiao Song; Ki Tae Nam

doi:10.1016/j.jcis.2025.01.132

Ultrathin Palladium-loaded Cuprous oxide stabilises Copper(I) to facilitate electrochemical carbon dioxide reduction reaction

J Colloid Interface Sci. 2025 Jan 20:685:537-545. doi: 10.1016/j.jcis.2025.01.132. Online ahead of print.

Authors

Xiaoye Du¹, Jaehyun Kim², Bo Gao³, Dan Qian¹, Chunhui Xiao⁴, Shujiang Ding⁴, Zhongxiao Song⁵, Ki Tae Nam⁶

Affiliations

¹ State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
² Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea.
³ School of Mechanical and Automotive Engineering, Qingdao University of Technology, Qingdao, Shandong 266525, China. Electronic address: gaobo@qut.edu.cn.
⁴ Xi'an Key Laboratory of Sustainable Energy Materials Chemistry, School of Chemistry, Xi'an Jiaotong University, Xi'an 710049, China.
⁵ State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China. Electronic address: zhongxiaosong@xjtu.edu.cn.
⁶ Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea. Electronic address: nkitae@snu.ac.kr.

PMID: 39855094
DOI: 10.1016/j.jcis.2025.01.132

Abstract

Cuprous oxide (Cu₂O) exhibit significant potential for catalytic activity in the electrochemical carbon dioxide reduction reaction (CO₂RR). However, the rapid reduction of Copper(I) (Cu⁺) to metallic Copper (Cu) leads to catalyst deactivation, significantly impacting product selectivity and stability. This study aims to stabilize the Cu⁺ valence state at a metal-Cu₂O heterogeneous interface through interfacial engineering, ultimately enhancing the electrochemical CO₂ reduction performance of Cu₂O. Utilizing comprehensive in situ Raman spectroscopy, we observed that the addition of Palladium (Pd) effectively inhibited the reduction of Cu₂O. Additionally, combined in situ attenuated total reflection Fourier-transform infrared spectroscopy and theoretical calculations revealed that Pd loading enhances *CO intermediate concentration and adsorption energy, and reduces the energy barrier for *CHO formation. The improved stability of the Cu⁺ valence state led to the coexistence of two CO adsorption modes including CO_atop and CO_bridge, promoting further CO hydrogenation and C-C coupling. Consequently, the Pd-loaded Cu₂O catalyst demonstrated remarkable electrochemical CO₂RR performance, achieving a methanol (CH₃OH) Faradaic efficiency of 78 %.

Keywords: CH(3)OH production; Catalytic mechanism; Cu(+) stability; Electrochemical CO(2) reduction; Pd loading.