Machine Learning Design of Single-Atom Catalysts for Nitrogen Fixation

First-principles calculations have been combined with machine learning in the design of transition-metal single-atom catalysts. Readily available descriptors are selected to describe the nitrogen activation capability of metals and coordinating atoms. Thus, a series of V/Nb/Ta-N_x single-atom catalysts are screened out as promising structures upon considering the stability, activity, and selectivity investigated computationally. Furthermore, by using the gradient boosting regression algorithm, an accurate prediction of the hydrogenation barriers for the nitrogen reduction reaction (NRR) is achievable, with a root-mean-squared error of 0.07 eV. The integration of high-throughput computation and machine learning constitutes a powerful strategy for the acceleration of catalyst design. This approach facilitates the rapid and accurate prediction of the NRR performance of more than 1000 single-atom catalyst structures. Moreover, the current work provides further insights by elaborately correlating the structure and performance, which may be instructive for both the design and application of vanadium-group catalysts.