A Density Functional Theory Study of Oxide-Supported Single-Atom Catalysts

Supported single metal atoms offer intriguing properties as heterogeneous catalysts. Typically supported on oxide surfaces, single-atom catalysts (SACs) may offer enhanced reactivity and selectivity while allowing for perfect dispersion of the expensive active metal component. However, single metal atoms are susceptible to sintering, a process by which the atoms agglomerate into larger, more thermodynamically stable nanoparticles. The loss of catalytic active sites from agglomeration compromises the SAC’s high reactivity. Stronger interfacial binding between the atom and oxide support reduces the rate of sintering and thereby results in smaller, more dispersed nanoparticles. Herein, strong interfacial binding is correlated with inherent properties of the metal and support, namely the metal’s oxide formation energy and the support’s reducibility. Using Density Functional Theory, the electronic effects of metal-support binding are studied, and an empirical screening tool for determining thermodynamically stable combinations of metals and oxide supports is developed.