Visible light responsive noble metal-free nanocomposite of V-doped TiO2 nanorod with highly reduced graphene oxide for enhanced solar H2 production

•Tailoring the band gap of anatase TiO2 into the visible region via vanadium doping.•Replacing precious metals by reduced graphene oxide (RGO) as a co-catalyst.•Preparation of V-doped TiO2 nanorods and RGO by a hydrothermal route.•Synergetic effect of nanocomposites as a new photocathode for H2 generation.

The visible light responsive nanocomposite of vanadium-doped TiO2 nanorod anchoring on highly reduced graphene oxide (RGO) has been successfully synthesized using a simple one step low temperature hydrothermal method. The nanoparticles, loaded on RGO, were intentionally fabricated as nanorods to enhance their contact with the RGO sheets. Compared to undoped TiO2 and non-composited V-TiO2 nanoparticles, the nanocomposite exhibited enhanced H2 evolution under visible light illumination. Density Functional Theory (DFT) computation also confirms the bandgap narrowing of TiO2 by doping vanadium. Furthermore, the photogenerated electrons could be effectively trapped by the conducting RGO sheets, thereby suppressing electron–hole recombination. This noble metal-free nanocomposite material composed of highly conducting sheets also offers promise for other energy applications such as lithium ion batteries.

Graphical abstractTailoring the bandgap of anatase TiO2 into the visible region via vanadium doping and the incorporation of reduced graphene oxide give the nanocomposites a synergetic effect for enhanced H2 production.Figure optionsDownload full-size imageDownload as PowerPoint slide