# Theoretical Insights into Hydrogen Production from Formic Acid Catalyzed by Pt-Group Single-Atom Catalysts

## TL;DR

This study uses theoretical calculations to explore how single-atom catalysts made of platinum-group metals can efficiently produce hydrogen from formic acid.

## Contribution

The paper introduces a new electronic descriptor for designing selective single-atom catalysts based on d-band center positions and metal-support interactions.

## Key findings

- Pd and Au SACs show significantly lower energy barriers for dehydrogenation compared to dehydration.
- Rh SACs have nearly equal energy barriers for both reaction pathways, showing poor selectivity.
- Metal-support interactions and charge transfer strongly influence catalytic performance and stability.

## Abstract

The rational development of single-atom catalysts (SACs) for selective formic acid dehydrogenation (FAD) requires an atomic-scale understanding of metal–support interactions and electronic modulation. In this study, spin-polarized density functional theory (DFT) calculations were performed to systematically examine platinum-group SACs anchored on graphitic carbon nitride (g-C3N4). The findings reveal that Pd and Au SACs exhibit superior selectivity toward the dehydrogenation pathway, lowering the free energy barrier by 1.42 eV and 1.39 eV, respectively, compared to the competing dehydration route. Conversely, Rh SACs demonstrate limited selectivity due to nearly equivalent energy barriers for both reaction pathways. Stability assessments indicate robust metal–support interactions driven by d–p orbital hybridization, while a linear correlation is established between the d-band center position relative to the Fermi level and catalytic selectivity. Additionally, charge transfer (ranging from 0.029 to 0.467 e) substantially modulates the electronic structure of the active sites. These insights define a key electronic descriptor for SAC design and offer a mechanistic framework for optimizing selective hydrogen production.