Yeast Reduced Ti3+ Self-Doped SrTiO3/rGO-In-Ni2P Nanocomposite for Efficient Visible Light-Driven Hydrogen Generation

• Published in: ACS applied nano materials Vol. 7; no. 14; pp. 16806 - 16822
• Main Authors: Suresh, Girisankar, Meera, Muraleedharan Sheela, Anil, Anaswara, George, Sneha, Shibli, Sheik Muhammadhu Aboobakar
• Format: Journal Article
• Language: English
• Published: American Chemical Society 26.07.2024
• Subjects: composite coating; photocatalytic water splitting; yeast assisted reduction; SrTiO3/yrGO-Ni2P; hydrogen generation
• ISSN: 2574-0970; 2574-0970
• DOI: 10.1021/acsanm.4c02880

SrTiO3 is a promising candidate for photocatalysis because of its tunable band structure and extreme stability. By suitably formulating nanocomposites of SrTiO3 with other materials, it can introduce defects into the crystal lattice and thereby alter its electronic structure favorably for the desired catalytic applications. In this study, a ternary composite in the form of a coating comprising of SrTiO3 nanocubes on yeast-reduced graphene oxide (yrGO) and Ni2P is developed for the generation of hydrogen by visible light-driven water splitting. The in situ tuning on the electronic state of SrTiO3 nanocubes by a self-doping effect from the controlled and simultaneous occurrence of Ti3+ species and oxygen vacancies via the Ti–C bond formation is achieved in the presence of a yeast-assisted reduction of GO in the SrTiO3/yrGO nanocomposite. Consequently, SrTiO3 forms epitaxially self-assembled SrTiO3 nanocubes on the surface of yrGO as a distinctive bush-like structure, which is further integrated with Ni2P matrix resulting in a hierarchical architecture consisting of SrTiO3/yrGO microflowers on the spherical Ni2P beds. This harmonious integration of SrTiO3/yrGO on Ni2P enriches the catalytically active sites facilitated by yrGO together with a straddling band gap alignment in the heterojunction for the efficient separation of the electron–hole pairs. The SrTiO3/yrGO-Ni2P composite coating heterojunction exhibits an outstanding performance toward solar light-driven water splitting and produces 13.25 mmol/g/h of hydrogen with an AQE value of 36.26% under 1 h irradiation after a successful compositional tuning on the coating surface.