Au nanoparticles modified oxygen-vacancies-rich Bi4Ti3O12 heterojunction for efficient photocatalytic NO removal with high selectivity

The photocatalytic removal of NO has been developed in the past ten years, but it is difficult to inhibit the production of NO2 during the NO oxidation process. In this study, Au nanoparticles loading oxygen-va-cancies-rich Bi4Ti3O12 nanospheres (Au/Bi4Ti3O12) were synthesized via a low temperature chemical method. The Au/Bi4Ti3O12 heterojunction shows an excellent NO removal rate of about 48% under visible light irradiation and significantly reduces the production of NO2. Au/Bi4Ti3O12 convert more NOx into nitrate and nitrite in the photocatalytic reaction. Such a high selectivity is attributed to the built-in electric field of Au/Bi4Ti3O12 heterojunction which promote the carrier separation. The increase of electron binding energy of each element indicates the transfer of electrons from BTO to Au nanoparticles. Importantly, the surface plasmon resonance effect originated from Au nanoparticles in heterojunction further increases the ad-sorption of visible light. Our work provides a feasible scheme for inhibiting the production of NO2 and increasing the NO stable oxide removal.(c) 2023 Elsevier B.V. All rights reserved.

Automated summary

The photocatalytic removal of NO with high selectivity and inhibition of NO2 production has been achieved by synthesizing Au/Bi4Ti3O12 heterojunctions. This is accomplished through the promotion of carrier separation by the built-in electric field of the heterojunction, as well as the transfer of electrons from BTO to Au nanoparticles. Additionally, the surface plasmon resonance effect of the Au nanoparticles further enhances the absorption of visible light, resulting in an excellent NO removal rate of about 48%.