Decoding the Electronic and Structural Fingerprints of Single-Atom Catalysts via DFT-Assisted XANES Analysis

TL;DR

This paper presents a DFT-assisted XANES analysis framework to accurately determine the electronic and structural features of single-atom catalysts, enabling better understanding and design of these highly efficient catalytic systems.

Contribution

The authors develop a DFT-based computational approach for interpreting XANES spectra, linking spectral features directly to atomic-scale structure and oxidation states of SACs.

Findings

Successfully identified oxidation states and coordination environments of Cu single atoms

Established a transferable method for correlating XANES spectra with atomic structures

Enhanced understanding of electronic structure in single-atom catalysts

Abstract

Single-atom catalysts (SACs), composed of isolated metal atoms dispersed on solid supports, represent the ultimate expression of atomic efficiency in catalysis. Their remarkable activity and selectivity arise from local coordination environments and adjustable oxidation states, yet precise determination of these features remains an enduring challenge. Among modern characterization techniques, X-ray absorption near-edge structure (XANES) spectroscopy stands out for its sensitivity to both electronic and geometric structure, though its interpretation is often constrained by empirical comparison with bulk references. Here we introduce a density functional theory (DFT) based computational spectroscopy framework for the quantitative interpretation of Cu K-edge XANES spectra. We then employ this framework to reveal the oxidation state, coordination geometry, and hydration environment of Cu single atoms supported on cyanographene, demonstrating direct correspondence between spectral signatures and atomic-scale structure. This methodology establishes a robust and transferable route for connecting XANES features with the underlying electronic and structural characteristics of SACs, thereby advancing the rational design of atomically precise catalysts.