Record-high photocatalytic rate at single atomic metal oxide

Metal oxides have been extensively investigated and applied in environmental remediation and protection, energy conversion and storage. Most of these diverse applications are results of a large diversity of the electronic states of metal oxides. Noticeably, however, numerous metal oxides have obstacles for applications in catalysis because of low density of active sites in these materials. Size reduction of oxide catalyst is a strategy to improve the active site density. Here, we demonstrate the fabrication of single atomic metal oxide in which the oxide size reaches its minimum. However, the catalytic mechanism in this SATO is determined by a quasi atom physics which is fundamentally distinct from the traditional size effect, and also is in contrast to the standard condensed matter physics. SATO results in a record high and stable sunlight photocatalytic degradation rate of 0.24, which exceeds those of available photocatalysis by approximately two orders of magnitude. The photocatalytic process is enabled by a quasi atom physical mechanism, in which, an electron in the spin up channel is excited from HOMO to LUMO+1 state, which can only occur in SATO with W5+.