Controlling Ni Photodeposition on Polyhedron SrTiO3 Effectively via Double-doped Al and Co

Abstract

SrTiO3 micron-nano-sized particles (MNPs) has been widely applied in photocatalysis field. Currently, more studies focus on the morphological control and heterojunction construction of SrTiO3, however, the unsuitable active sites have limited their performance improvements. In this article, we developed a polyhedron SrTiO3 MNPs double doped with Al and Co, which showed the outstanding in situ photo-reduction performance of Ni2+ (from Ni2+ to Ni0), about 39% improvement in 10 minutes comparing with the traditional sample only doped with Al, benefited from the unique strengthening function of crystal facet effect. The photo-reduction reaction of Ni2+ exhibited a significant selectivity on (112) crystal facet mainly due to the changes in surface structure including the atomic nanoclusters (ACs) and the satellite single atom (SAs) of Co. The femtosecond transient absorption spectrum (fs-TA) revealed the difference of excited states of photo-induced electrons in the same delay-time, which was the essence of synergistic effect between ACs and SAs. Originating from above characteristics, the double-doped SrTiO3 has high-efficiency selective photodeposition only for Ni. In addition, we established an experimental platform of the photo-quantum absorption efficiency of aqueous dispersion system to verify the Ni may be an effective active site in photocatalytic process for SrTiO3. Therefore, this work demonstrated the special SrTiO3 MNPs had a huge potential application in the field of Ni recycle of wastewater or cocatalyst construction.