title: Faceted titania nanocrystals doped with indium oxide nanoclusters as a superior candidate for sacrificial hydrogen evolution without any noble-metal cocatalyst under solar irradiation.
abstract: Development of unique nanoheterostructures consisting of indium oxide nanoclusters like species doped on the TiO2 nanocrystals surfaces with {101} and {001} exposed facets, resulted in unprecedented sacrificial hydrogen production (5.3 mmol h(-1) g(-1)) from water using methanol as a sacrificial agent, under visible light LED source and AM 1.5G solar simulator (10.3 mmol h(-1) g(-1)), which is the highest H2 production rate ever reported for titania based photocatalysts, without using any noble metal cocatalyst. X-ray photoelectron spectroscopy (XPS) analysis of the nanostructures reveals the presence of Ti-O-In and In-O-In like species on the surface of nanostructures. Electron energy-loss spectroscopy (EELS) elemental mapping and EDX spectroscopy techniques combined with transmission electron microscope evidenced the existence of nanoheterostructures. XPS, EELS, EDX, and HAADF-STEM tools collectively suggest the presence of indium oxide nanoclusters like species on the surface of TiO2 nanostructures. These indium oxide nanocluster doped TiO2 (In2O3/T{001}) single crystals with {101} and {001} exposed facets exhibited 1.3 times higher visible light photocatalytic H2 production than indium oxide nanocluster doped TiO2 nanocrystals with only {101}facets (In2O3/T{101}) exposed. The remarkable photocatalytic activity of the obtained nanoheterostructures is attributed to the combined synergetic effect of indium oxide nanoclusters interacting with the titania surface, enhanced visible light response, high crystallinity, and unique structural features.
authors.affiliation: CSIR-Indian Institute of Petroleum , Dehradun 248005, India.
authors.forename: Vipin
authors.initials: V
authors.lastname: Amoli
authors.forename: Malayil Gopalan
authors.initials: MG
authors.lastname: Sibi
authors.forename: Biplab
authors.initials: B
authors.lastname: Banerjee
authors.forename: Mohit
authors.initials: M
authors.lastname: Anand
authors.forename: Abhayankar
authors.initials: A
authors.lastname: Maurya
authors.forename: Saleem Akhtar
authors.initials: SA
authors.lastname: Farooqui
authors.forename: Asim
authors.initials: A
authors.lastname: Bhaumik
authors.forename: Anil Kumar
authors.initials: AK
authors.lastname: Sinha
keywords: faceted titania nanocrystals; indium oxide nanoclusters; nanoheterostructures; sacrificial hydrogen production; synergetic effect; water splitting