Hybrid DFT study of MWCNT/Zr-doped SrTiO3 heterostructure: Hydrogen production, electronic properties and charge Carrier mediator role of Zr4+ ion

Abstract

Over the past decade, remarkable efforts have been made to design low-cost, non-toxic, stable and efficient photocatalyst for water splitting. In the present work, an effective alternative approach to enhance hydrogen production of SrTiO(sub)3 was by coupling with MWCNT to form heterojunction followed by doping with Zr(sup)4+ ion. The observed type-II band alignment and the polarised electric field could promote the separation of photoexcited charge carriers and photocatalytic activity of these hybrid heterostructures. The theoretical calculation revealed that Zr(sup)4+ ion could act as a charge carrier mediator to transfer electrons to the SrTiO(sub)3 surface. The MWCNT (6,12,18)/Zr-doped SrTiO(sub)3(100) heterostructure exhibited excellent activity due to the combined effect of MWCNT (6,12,18) and Zr-doped SrTiO(sub)3(100) monolayers compared with pure SrTiO(sub)3. This study offers a novel understanding of designing highly active and stable SrTiO(sub)3-based photocatalyst as efficient hydrogen generation material.