Single Layer of Polymeric Metal–Phthalocyanine: Promising Substrate to Realize Single Pt Atom Catalyst with Uniform Distribution

Single atom catalysts (SAC) are highly desirable to maximize atom efficiency, while fabricating them is largely dependent on choosing a suitable substrate to effectually fasten them. Here, in terms of strong metal–metal interaction, first-principle calculations have been performed to study the possibility of monolayer polymeric transition metal–phthalocyanines (TM–Pcs, M from Sc to Zn) as the substrate in an effect to obtain evenly distributed single Pt atom catalyst. We found that Ti–Pc is the most appropriate compound by virtue of high binding strength of Pt/Ti–Pc system and high diffusion energy barrier of Pt catalyst atom, which jointly prevent the formation of Pt clusters. CO oxidation on Pt/Ti–Pc presents some unexpected behaviors, where a presorbed CO (pCO) molecule could activate the catalyst and reduce the reaction barrier. Examining the electronic structure evolution in the reaction process demonstrates that the presence of a pCO promotes O2 adsorption and activation. Our results demonstrate that two-dimensional (2D) TM–Pcs provide a unique platform to fabricate regularly and separately distributed SAC with high activity.