An isolation strategy to anchor atomic Ni or Co cocatalysts on TiO2 (A) for photocatalytic hydrogen production

TiO2 has been considered as an ideal photocatalyst for water splitting. However, narrow light absorbance, low charge separation efficiency, and rare surface active sites lead to the low photocatalytic efficiency of TiO2. Although extensive research attempted to improve the situation, there is still lack of method for constructing high active and noble-metal-free TiO2 photocatalyst for H-2 evolution reactions (HER). In this work, we loaded single atomic (SA) Ni (or Co) on the surface of anatase TiO2 (TiO2 (A)) nanosheets by an isolation strategy. Ethylene diamine tetraacetic acid and ethylene glycol (EDTA-EG) compounds were used to chelate metal ions in solution and form carbon quantum dots in the following thermal treatment to isolate the metal ions on surface of TiO2(A). The prepared Ni SA/TiO2 (A) catalyst owned a skin wrapped body structure with in-situ formed twodimensional (2D) heterojunction facilitating the fast electron transfer. As a result, the Ni SA/TiO2 (A) catalyst showed a high H-2 evolution rate of 2,900 mu mol.g(-1).h(-1). This work provides an isolation strategy for constructing promising single-atom metal catalyst for photocatalysis and beyond.

Automated summary

TiO2 as a photocatalyst for water splitting has low efficiency due to narrow light absorbance, low charge separation efficiency, and rare surface active sites. This study loaded single atomic Ni (or Co) on the surface of anatase TiO2 nanosheets, forming a two-dimensional heterojunction, leading to high efficiency H-2 evolution reaction.