SAIP2025

METHANOL FORMATION FROM SYNGAS ON ZnO (010) SURFACE: INSIGHTS FROM DFT

Not scheduled

20m

Solomon Mahlangu House (University of the Witwatersrand, Johannesburg)

Poster Presentation Track A - Physics of Condensed Matter and Materials Poster Session

Speaker

Dr Tshegofatso Phaahla (University of Limpopo)

Description

The synthesis of methanol from syngas (CO/CO₂/H₂) via hydrogenation on the ZnO (010) surface supported by CuPd cluster has been studied using periodic density functional theory (DFT) calculations. Our findings indicate that direct hydrogenation of CO₂ to methanol is selective. In the presence of surface atomic hydrogen and oxygen, CO₂ tends to form highly stable formate (HCOO) and formyl (HCO). Conversely, methanol production through CO hydrogenation is both thermodynamically and kinetically viable. CO undergoes successive hydrogenation steps, forming intermediates such as formyl (HCO), formaldehyde (H₂CO), and methoxy (H₃CO), ultimately yielding methanol (H₃COH). In the sequential hydrogenation of CO, the rate-limiting step is the conversion of methoxy (H₃CO) to methanol (H₃COH). Notably, the presence of CuPd cluster significantly promotes this final hydrogenation step, reducing the adsorption energy from -0.65 eV to -3.25 eV.