Modulating the Cu<sub>2</sub>O Photoelectrode/Electrolyte Interface with Bilayer Surfactant Simulating Cell Membranes for Boosting Photoelectrochemical CO<sub>2</sub> Reduction
Yanfang Zhang, Weixin Qiu, Yang Liu, Keke Wang, Wenyuan Li, Wenyuan Li, Jihu Kang, Xiaoqing Qiu, Min Liu, Wenzhang Li, Wenzhang Li, Jie Li
Abstract
The low solubility of CO 2 molecules and the competition of the hydrogen evolution reaction (HER) in aqueous electrolytes pose significant challenges to the current photoelectrochemical (PEC) CO 2 reduction reaction. In this study, inspired by the bilayer phospholipid molecular structure of cell membranes, we developed a Cu 2 O/Sn photocathode that was modified with the bilayer surfactant DHAB for achieving high CO 2 permeability and suppressed HER. The Cu 2 O/Sn/DHAB photocathode stabilizes the *OCHO intermediate and facilitates the production of HCOOH. Our findings show that the Faradaic efficiency (FE) of HCOOH by the Cu 2 O/Sn/DHAB photoelectrode is 83.3%, significantly higher than that achieved with the Cu 2 O photoelectrode (FE HCOOH = 30.1%). Furthermore, the FE H2 produced by the Cu 2 O/Sn/DHAB photoelectrode is only 2.95% at −0.6 V vs RHE. The generation rate of HCOOH by the Cu 2 O/Sn/DHAB photoelectrode reaches 1.52 mmol·cm –2 ·h –1 ·L –1 at −0.7 V vs RHE. Our study provides a novel approach for the design of efficient photocathodes for CO 2 reduction.