DFT Study of Copper-Based Single-Atom Alloy for Conversion of Carbon Dioxide to Formic Acid

Transforming carbon dioxide (CO 2 ) into value-added chemicals is an innovative approach to tackling environmental issues and reducing greenhouse impacts. Owing to the excellent synergistic interaction between substrates and dopants, single-atom alloys (SAAs) exhibit promising catalytic performance in converting CO 2 into valuable chemicals. In this theoretical investigation, we employed DFT to explore the catalytic potential of single-atom-doped Cu(111) surfaces in the conversion of CO 2 to formic acid (HCOOH). Our investigation provides an in-depth analysis of the catalytic properties of Pd/Cu(111) and Pt/Cu(111) surfaces in relation to the Cu(111) surface. We have identified that *CO 2 hydrogenation to *HCOO is the rate-determining step. This step exhibits greater kinetic feasibility on the Pd/Cu(111) surface than on the Pt/Cu(111) surface. The electronic state analysis reveals that the single atoms doped in the Cu(111) surface modify the local chemical environment at the nanoscale. The microkinetic simulation results indicate that Pd/Cu(111) achieves the highest turnover frequency (TOF), with a value of 3.78 × 10 –5 s –1 ·site –1 at 500 K and 30 bar, identifying it as a promising catalyst for CO 2 hydrogenation. Additionally, our findings suggest that adjusting temperatures at a constant pressure can lead to stabilization of the TOF values on Pd/Cu(111). This work contributes valuable insights for screening effective SAAs in CO 2 hydrogenation to HCOOH, offering a promising direction for the development of catalyst design for HCOOH production.