Synthesis of Mesoporous Silica-Embedded TiO₂ Loaded with Ag Nanoparticles for Photocatalytic Hydrogen Evolution from Water Splitting

胡秀丽^1,2，XIAO Leqin¹，JIAN Xiaoxia¹，ZHOU Weiliang¹

1. School of Chemical Engineering, Nanjing University of Science and Technology2. School of Chemistry and Materials Engineering, Changshu Institute of Technology

摘 要：Ag loaded mesoporous silica-embedded TiO₂ nanocomposites were successfully synthesized via two different routes,including one-pot solvothermal method and solvothermal-chemical reduction method,both using Titanium（Ⅳ） n-butoxide（Ti（OC₄H₉）₄） as a precursor,formic acid as a solvent and reducing agent,silver nitrate as a silver source and tetraethyl silicate（TEOS） as a stabilizer.The transmission electron microscopic（TEM） images showed that silica-embedded anatase TiO₂ sample exhibited approximately rhombic shape and Ag nanoparticles could be embedded into the nanocomposites or deposited on the surface with high dispersion.The N₂ adsorption-desorption isotherms indicated that the silica-embedded anatase TiO₂ had obvious mesoporous structure with a BET specific surface area of 203.5 m²·g^-1.All Ag loaded silica-embedded TiO₂composites showed a higher photocatalytic H₂-generation activity from water splitting under simulative solar light irradiation than that of TiO₂ products.The maximum H₂ production rate(6.10 mmol·h^-1·g^-1) was obtained over 2%Ag/silica-embedded TiO₂ nanocomposites（2%Ag/MST） prepared by solvothermal-chemical reduction method,which was 20 times that achieved on the silica-embedded TiO₂ sample.The enhanced photocatalytic H₂-evolution activity of Ag loaded mesoporous silica-embedded TiO₂ nanocomposites can be attributed to the multi-function of surface Ag co-catalyst,mesoporous structure,and embedding of silica.

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