Oxygen vacancy (O_v) significantly influences the oxidation process through oxygen adsorption and activation. Element doping can fabricate oxygen vacancy on titanium dioxide (TiO₂), but the effects of the dopants on the oxidation reaction over oxygen vacancy remain unclear.

A research team from the Research Center for Eco-Environmental Sciences of the Chinese Academy of Sciences has recently fabricated oxygen vacancy by doping nitrogen into anatase TiO₂. Their results were published in Cell Reports 糖心视频ical Science.

To fabricate oxygen vacancy with different structures, the researchers doped nitrogen (N) and boron (B) into anatase TiO₂ (N-TiO₂ and B-TiO₂). Both N^-鈥揟颈³⁺鈥揙_v and Ti₃⁺鈥揙_v were observed in N-TiO₂, but only Ti³⁺鈥揙_v in TiO₂ and B-TiO₂. The results showed that N^-鈥揟颈³⁺鈥揙_v is more reactive than Ti³⁺鈥揙_v in O₂ activation.

In addition, the N^-鈥揟颈³⁺鈥揙_v active sites formed in N-TiO₂ significantly enhance the thermal yield and selectivity of the oxidation of the primary C鈥揌 bonds in toluene.

The adsorption and activation of O₂ are the rate-limiting step in the selective oxidation of primary C鈥揌 bonds in toluene. N^-鈥揟颈³⁺鈥揙_v as electron donors contributed to a rapid formation of superoxygen species (路O₂^-), which demonstrated to be active oxygen for primary C鈥揌 bond oxidation.

The fabrication of N^-鈥揟颈³⁺鈥揙_v sites opens a new avenue for dopants to improve the oxygen vacancy reactivity and enhance the primary C鈥揌 oxidation selectivity.