Visible-light active mesoporous, nanocrystalline N,S-doped and co-doped titania photocatalysts synthesized by non-hydrolytic sol-gel route

详细信息    查看全文

• 作者：Asma Juma Albrbar^a ; Veljko Djokić^a ; Andjelika Bjelajac^b ; Janez Kovač^c ; Jovana Ćirković^d ; Miodrag Mitrić^e ; Djordje Janaćković^a ; Rada Petrović^a ; ^{radaab@tmf.bg.ac.rs" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Visible-light photocatalytic activity ; Non-hydrolytic sol-gel processing ; Mesoporosity ; N ; S-doped TiO2
• 刊名：Ceramics International
• 出版年：2016
• 出版时间：15 November 2016
• 年：2016
• 卷：42
• 期：15
• 页码：16718-16728
• 全文大小：4081 K

文摘

Visible-light active mesoporous N,S-doped and co-doped anatase TiO₂ powders were synthesized by non-hydrolytic sol-gel route, starting from TiCl₄ and Ti(OⁱPr)₄ dissolved in cyclohexane or dimethyl sulfoxide, later used as a S-doping agent. After drying in an inert atmosphere, the gels were annealed at 500 °C for 3 h, in air or ammonia flow, later used for N-doping. The undoped titania powder, obtained by annealing in air of the cyclohexane-based gel, was also annealed in ammonia to deduce which method is more efficient for N-doping: gel or powder annealing. The post-annealing in air after annealing in ammonia was optimized to attain the best photocatalytic activity for dye degradation under simulated visible light. The size of anatase nanocrystals decreased by doping and the specific surface area of the powders increased. The XPS analysis confirmed a successful substitution of Ti⁴⁺ by S(4+) and/or S(6+), which caused a very small band-gap narrowing. The gel annealing in ammonia was much more efficient for interstitial nitrogen incorporation in TiO₂ lattice than the powder annealing. The annealing in ammonia of the gel synthesized with dimethyl sulfoxide provided the highest visible-light activity owing to high specific surface area, appropriate mesoporosity and high photoabsorption due to efficient N,S co-doping.