Influence of Magnetic Moment on Single Atom Catalytic Activation Energy Barriers

Design of the molecular environment of single atom catalysts (SAC) is promising for achieving high catalytic activity without expensive and scarce platinum-group metals (PGM). We utilize a first principles approach to examine how the spin state of the SAC and reactants can affect catalytic energy barriers of V, Fe, Mo, and Ta on two different graphene defects with differing magnetic moments. Spin polarized projected density of states and climbing image nudged elastic band calculations demonstrate relatively lower activation energy barriers for systems with higher spin state asymmetry near the Fermi energy; CO oxidation on Ta and V SAC have decreases in activation barrier energies of 27% and 44%, respectively. [GRAPHICS] .

Automated summary

The design of the molecular environment of single atom catalysts offers a promising way to achieve high catalytic activity without the need for expensive platinum-group metals. This study utilized a first principles approach to examine the impact of spin states on the catalytic energy barriers of V, Fe, Mo, and Ta on graphene defects. Results showed that systems with higher spin state asymmetry near the Fermi energy had relatively lower activation energy barriers, leading to significant decreases in activation barrier energies for CO oxidation on Ta and V catalysts.