Revealing the Lattice Carbonate Mediated Mechanism in Cu₂(OH)₂CO₃ for Electrocatalytic Reduction of CO₂ to C₂H₄.

ABSTRACT: Understanding the CO₂ transformation mechanism on materials is essential for the design of efficient electrocatalysts for CO₂ reduction. In aconventional adsorbate evolution mechanism (AEM), the catalysts encounter multiple high-energy barrier steps, especially CO₂ activation, limiting the activity and selectivity. Here, lattice carbonate from Cu₂(OH)₂CO₃ is revealed to be a mediator between CO₂ molecules and catalyst during CO₂ electroreduction by a ¹³C isotope labeling method, which can bypass the high energy barrier of CO₂ activation and strongly enhance the performance. With the lattice carbonate mediated mechanism (LCMM), the Cu₂(OH)₂CO₃ electrode exhibited ten-fold faradaic efficiency and 15-fold current density for ethylene production than the Cu₂O electrode with AEM at a low overpotential. Theoretical calculations and in situ Raman spectroscopy results show that symmetric vibration of carbonate is precisely enhanced on the catalyst surface with LCMM, leading to faster electron transfer, and lower energy barriers of CO₂ activation and carbon-carbon coupling. This work provides a route to develop efficient electrocatalysts for CO₂ reduction based on lattice-mediated mechanism.

SUBMITTER: Gao Y 

PROVIDER: S-EPMC11005744 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature