Quantum Monte Carlo method modeling supported metal catalysis: Ni(111) converting adsorbed formyl 'en route' to hydrogen

Abstract: Hydrogen production as a clean, sustainable replacement for fossil fuels is gathering pace. Doubling the capacity of Paris-CDG airport has been halted, even with the upcoming Olympic Games, until hydrogen-powered planes can be used. It is thus timely to work on catalytic selective hydrogen production and optimise catalyst structure. Over 90 % of all chemical manufacture uses a solid catalyst. This work describes the dissociation of a C-H bond in formyl radicals, chemisorbed at Ni(111) that stabilises the ensuing Ni-H linkage. As part of this mechanistic step, gaseous hydrogen is given off. Many chemical reactions involve bond-dissociation. This process is often the key to rate-limiting reaction steps at solid surfaces. Since bond-breaking is poorly described by Hartree-Fock and DFT methods, our embedded active site approach is used. This work demonstrates Quantum Monte Carlo (QMC) methodology using a very simple monolayer Ni(111) surface model.