Electrochemical coupling between carbon and nitrogen
species to
generate high-value C–N products, including urea, presents
significant economic and environmental potentials for addressing the
energy crisis. However, this electrocatalysis process still suffers
from limited mechanism understanding due to the complex reaction networks,
which restricts the development of electrocatalysts beyond trial-and-error
practices. In this work, we aim to improve the understanding of the
C–N coupling mechanism. This goal was achieved by constructing
the activity and selectivity landscape on 54 MXene surfaces by density
functional theory (DFT) calculations. Our results show that the activity
of the C–N coupling step is largely determined by the *CO adsorption
strength (E
ad‑CO), while the selectivity
relies more on the co-adsorption strength of *N and *CO (E
ad‑CO and E
ad‑N). Based on these findings, we propose that an ideal C–N coupling
MXene catalyst should satisfy moderate *CO and stable *N adsorption.
Through the machine learning-based approach, data-driven formulas
for describing the relationship between E
ad‑CO and E
ad‑N with atomic physical
chemistry features were further identified. Based on the identified
formula, 162 MXene materials were screened without time-consuming
DFT calculations. Several potential catalysts were predicted with
good C–N coupling performance, such as Ta2W2C3. The candidate was then verified by DFT calculations.
This study has incorporated machine learning methods for the first
time to provide an efficient high-throughput screening method for
selective C–N coupling electrocatalysts, which could be extended
to a wider range of electrocatalytic reactions to facilitate green
chemical production.