Engineering Pt single atom catalyst with abundant lattice oxygen by dual nanospace confinement strategy for the efficient catalytic elimination of VOCs

Abstract

Precisely constructing Pt single atom catalyst (SACs) with fine-tuned chemical environments is a vitally challenging issue, which has attracted peoples’ attentions. The activation of lattice oxygen linked to active sites is also a great challenge to heterogeneous catalysis. Herein, via a cage-encapsulating strategy, Pt single atom (SA) was accurately constructed by dual nanospace confinement of three-dimensional ordered macroporous (3DOM) CeO2 pore and Ce-MOFs nanocages. During calcination, CeO2 derived from Ce-MOF restricted the migration of Pt SA and prevented its agglomeration. With the construction of CeO2 nanocage, more active Pt-O2 bond was created. More active lattice oxygen was linked to Pt single atom. DFT calculation also confirmed VOCs molecules were more easily absorbed on the catalyst surface and CO was more easily oxidized to CO2. The 90% conversion temperature (T90) of Pt1/CeO2 @CeO2-0.2 (T90 = 268 °C) was 81 °C lower than the T90 of Pt1/CeO2 (T90 = 349 °C) on the catalytic combustion of benzene.