Role of catalyst carriers in CO₂ photoreduction over nanocrystalline nickel loaded TiO₂-based photocatalysts

详细信息    查看全文

• 作者：Oluwafunmilola Ola ; M. Mercedes Maroto-Valer
• 关键词：Nickel ; Photocatalysis ; Quartz plate ; Monolith photoreactor ; Titanium dioxide ; Heterojunction
• 刊名：Journal of Catalysis
• 出版年：January, 2014
• 年：2014
• 卷：309
• 期：Complete
• 页码：300-308
• 全文大小：1929 K

文摘

Nickel-based TiO₂ photocatalysts were immobilized onto carriers (quartz plates and monoliths) in a unique reactor configuration to provide a high ratio of illuminated surface area of catalyst for the reduction in CO₂ to fuels under UV and visible light. The incorporation of Ni²⁺ in the TiO₂ matrix inhibits the grain growth of anatase crystallites and suppresses phase transformation. The Ni²⁺ atom is also found to be replacing some of the Ti atoms in the crystal lattice of TiO₂ during the sol-gel method, thus causing a change in optical absorption. Using water as a reductant, vapour-phase CO₂ was reduced to fuels with the monolith threaded with optical fibres and quartz plate photoreactor system following 4 h of light irradiation. More importantly, the improved conversion efficiency is ascribed to the presence of Ni²⁺ species which served as electrons traps that suppressed recombination, resulting in effective charge separation and CO₂ reduction.