pH effects on the electrochemical reduction of CO(2) towards C2 products on stepped copper
Abstrak
We present a microkinetic model for CO(2) reduction (CO(2)R) on Cu(211) towards C2 products, based on energetics estimated from an explicit solvent model. We show that the differences in both Tafel slopes and pH dependence for C1 vs C2 activity arise from differences in their multi-step mechanisms. We find the depletion in C2 products observed at high overpotential and high pH to arise from the 2nd order dependence of C-C coupling on CO coverage, which decreases due to competition from the C1 pathway. We further demonstrate that CO(2) reduction at a fixed pH yield similar activities, due to the facile kinetics for CO2 reduction to CO on Cu, which suggests C2 products to be favored for CO2R under alkaline conditions. The mechanistic insights of this work elucidate how reaction conditions can lead to significant enhancements in selectivity and activity towards higher value C2 products. CO2 conversion to reduced products provides a use for greenhouse gases, but reaction complexity stymies mechanistic studies. Here, authors present a microkinetic model for CO2 and CO reduction on copper, based on ab initio simulations, to elucidate pH’s impact on competitive reaction pathways.
Penulis (14)
Xinyan Liu
P. Schlexer
Jianping Xiao
Yongfei Ji
Lei Wang
Robert B. Sandberg
Michael T. Tang
Kristopher S. Brown
Hongjie Peng
Stefan Ringe
C. Hahn
T. Jaramillo
J. Nørskov
Karen Chan
Akses Cepat
- Tahun Terbit
- 2019
- Bahasa
- en
- Total Sitasi
- 479×
- Sumber Database
- Semantic Scholar
- DOI
- 10.1038/s41467-018-07970-9
- Akses
- Open Access ✓