Solving the structure of "single-atom" catalysts using machine learning - assisted XANES analysis.

Phys Chem Chem Phys

Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794, USA.

Published: February 2022

AI Article Synopsis

  • "Single-atom" catalysts (SACs) show impressive efficiency in difficult chemical reactions, like converting CO using light.
  • To understand how these SACs work, it's crucial to analyze their atomic-level structure, which was done by attaching a cobalt catalyst to a special carbon nitride surface.
  • Various machine learning techniques, like principal component analysis and neural networks, were applied to analyze the sensitive X-ray absorption data, providing detailed insights into the local atomic environment of the SAC.

Article Abstract

"Single-atom" catalysts (SACs) have demonstrated excellent activity and selectivity in challenging chemical transformations such as photocatalytic CO reduction. For heterogeneous photocatalytic SAC systems, it is essential to obtain sufficient information of their structure at the atomic level in order to understand reaction mechanisms. In this work, a SAC was prepared by grafting a molecular cobalt catalyst on a light-absorbing carbon nitride surface. Due to the sensitivity of the X-ray absorption near edge structure (XANES) spectra to subtle variances in the Co SAC structure in reaction conditions, different machine learning (ML) methods, including principal component analysis, K-means clustering, and neural network (NN), were utilized for Co XANES data analysis. As a result, we obtained quantitative structural information of the SAC nearest atomic environment, thereby extending the NN-XANES approach previously demonstrated for nanoparticles and size-selective clusters.

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http://dx.doi.org/10.1039/d1cp05513eDOI Listing

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