Metal link: A strategy to combine graphene and titanium dioxide for enhanced hydrogen production. (21st December 2016)

• Record Type: Journal Article
• Authors: Wang, Zhouyou; Yin, Yichun; Williams, Tim; Wang, Huanting; Sun, Chenghua; Zhang, Xiwang
• Is Part Of: International journal of hydrogen energy. Volume 41:Number 47(2016)
• Page Start: 22034
• Page End: 22042
• Publication Date: 2016-12-21
• Subjects: Titanium dioxide -- Hydrogen production -- Metal link -- Graphene; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2016.08.102
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: This communication addresses the key issues of titanium dioxide (TiO2 ) for hydrogen production through water splitting: wide band gap, low conductivity and large overpotential, through a novel strategy — metal links, which connect TiO2 and graphene to form a ternary junction (TiO2 /Ag@graphene). Silver (Ag) nanoparticles are identified as an excellent link and successfully deposited on TiO2, not only collecting and transferring photo-excited electrons from TiO2 to graphene, but also harvesting more photons through the effect of surface plasmon resonance (SPR). Such TiO2 /Ag@graphene junctions improve the hydrogen production rate by three times with respect to the original TiO2 . It is expected that the concept of metal links can be employed as a general approach to improve the performance of semiconductor-based photocatalysts. Graphical abstract: A novel strategy — metal links, which connect TiO2 and graphene to form a ternary junction (TiO2 /Ag@graphene) is developed. Silver (Ag) nanoparticles not only collect and transfer photo-excited electrons from TiO2 to graphene but also harvest more photons through the effect of surface plasmon resonance (SPR). Such TiO2 /Ag@graphene junctions improve the hydrogen production rate by three times with respect to the original TiO2 . Highlights: A new ternary core–shell structure containing TiO2, Ag and rGO was designed and fabricated via solvothermal reaction. A new "metal-link" concept was proposed for the synergetic combination of TiO2, Ag and rGO. The role of the metal-link was clarified based on density functional theory calculation and experimental validation. In addition to the enhancement of transfer of photo-excited electrons, Ag nanoparticles harvest more photons. A three-fold improvement to hydrogen production was achieved by Ag/TiO2 @rGO.