Microkinetic Modeling of CO2 Hydrogenation to Formic Acid on Transition Metal Doped Ni(111) Surface

Abstract

The direct conversion of carbon dioxide (CO2) into valuable chemicals plays a crucial role in mitigating climate change and fostering a sustainable future. To facilitate this process, identifying an effective catalyst is of utmost importance. This study focuses on investigating the potential of nickel-based surfaces as catalysts for the direct hydrogenation of CO2 into formic acid (HCOOH), a valuable chemical with applications as a fuel and hydrogen storage. Several nickel surface models were considered, including pristine Ni(111) and Ni(111) surfaces doped with Cu, Pd, Pt, and Rh metals. Through a microkinetic investigation, we examined the reaction kinetics and determined the rate-determining steps on the Ni(111) surfaces. By elucidating the reaction pathways and characterizing the reaction intermediates, we gained comprehensive insights into the fundamental processes involved in CO2 hydrogenation to HCOOH. This knowledge is crucial for the rational design and optimization of catalysts, enabling the development of highly active catalysts for CO2 conversion. Our study revealed insights into the effect of transition metal doping on the catalytic activity of Ni(111) surfaces. Among the investigated dopants, we found that the addition of Pt in the first layer of Ni(111) surface yielded the best turnover frequency (TOF) for the CO2 conversion to HCOOH. The Pt dopants induced unique electronic properties in the Ni(111) surface, resulting in a reduced activation barrier for key reaction intermediates. This effect contributed to a more efficient conversion of CO2 to HCOOH.