Visible light-driven H2 production over highly dispersed Ruthenia on Rutile TiO2 nanorods

The immobilization of miniscule quantities of RuO2 (~0.1%) onto one-dimensional (1D) TiO2 nanorods (NRs) allows H2 evolution from water under visible light irradiation. Rod-like rutile TiO2 structures, exposing preferentially (110) surfaces, are shown to be critical for the deposition of RuO2 to enable photocatalytic activity in the visible region. The superior performance is rationalized on the basis of fundamental experimental studies and theoretical calculations, demonstrating that RuO2(110) grown as 1D nanowires on rutile TiO2(110), which occurs only at extremely low loads of RuO2, leads to the formation of a heterointerface that efficiently adsorbs visible light. The surface defects, band gap narrowing, visible photoresponse, and favorable upward band bending at the heterointerface drastically facilitate the transfer and separation of photogenerated charge carriers.Peer ReviewedPostprint (published version

Water-gas-shift over metal-free nanocrystalline ceria: an experimental and theoretical study

A tandem experimental and theoretical investigation of a mesoporous ceria catalyst reveals the properties of the metal oxide are conducive for activity typically ascribed to metals, suggesting reduced Ce3+ and oxygen vacancies are responsible for the inherent bi-functionality of CO oxidation and dissociation of water required for facilitating the production of H-2. The degree of reduction of the ceria, specifically the (100) face, is found to significantly influence the binding of reagents, suggesting reduced surfaces harbor the necessary reactive sites. The metal-free catalysis of the reaction is significant for catalyst design considerations, and the suite of in situ analyses provides a comprehensive study of the dynamic nature of the high surface area catalyst system. This study postulates feasible improvements in catalytic activity may redirect the purpose of the water-gas shift reaction from CO purification to primary hydrogen production.Peer ReviewedPostprint (author's final draft

Water-gas-shift over metal-free nanocrystalline ceria: an experimental and theoretical study

A tandem experimental and theoretical investigation of a mesoporous ceria catalyst reveals the properties of the metal oxide are conducive for activity typically ascribed to metals, suggesting reduced Ce3+ and oxygen vacancies are responsible for the inherent bi-functionality of CO oxidation and dissociation of water required for facilitating the production of H-2. The degree of reduction of the ceria, specifically the (100) face, is found to significantly influence the binding of reagents, suggesting reduced surfaces harbor the necessary reactive sites. The metal-free catalysis of the reaction is significant for catalyst design considerations, and the suite of in situ analyses provides a comprehensive study of the dynamic nature of the high surface area catalyst system. This study postulates feasible improvements in catalytic activity may redirect the purpose of the water-gas shift reaction from CO purification to primary hydrogen production.Peer Reviewe

Visible light-driven H2 production over highly dispersed Ruthenia on Rutile TiO2 nanorods

The immobilization of miniscule quantities of RuO2 (~0.1%) onto one-dimensional (1D) TiO2 nanorods (NRs) allows H2 evolution from water under visible light irradiation. Rod-like rutile TiO2 structures, exposing preferentially (110) surfaces, are shown to be critical for the deposition of RuO2 to enable photocatalytic activity in the visible region. The superior performance is rationalized on the basis of fundamental experimental studies and theoretical calculations, demonstrating that RuO2(110) grown as 1D nanowires on rutile TiO2(110), which occurs only at extremely low loads of RuO2, leads to the formation of a heterointerface that efficiently adsorbs visible light. The surface defects, band gap narrowing, visible photoresponse, and favorable upward band bending at the heterointerface drastically facilitate the transfer and separation of photogenerated charge carriers.Peer Reviewe