Bio-Template Mediated In Situ Phosphate Transfer to Hierarchically Porous TiO2 with Localized Phosphate Distribution and Enhanced Photoactivities

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• 作者：Tao He ; Yonggen Weng ; Peng Yu ; Chuanlin Liu ; Haiqin Lu ; Yuanping Sun ; Shangzhou Zhang ; Xin Yang ; Guoqun Liu
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：March 6, 2014
• 年：2014
• 卷：118
• 期：9
• 页码：4607-4617
• 全文大小：769K
• 年卷期：v.118,no.9(March 6, 2014)
• ISSN：1932-7455

文摘

A localized phosphate distribution (LPD) was introduced for the first time into a porous TiO₂ nanostructure by using a biotemplate synthetic strategy, that is, Staphylococcus aureus (S. aureus)-assisted in situ phosphate transfer. The resulting novel nanostructures have shown remarkable enhancement of photoactivities for both selective dye degradation and photoelectrochemical water reduction. Mechanistic understanding reveals that improved separation, directional transport, and less limited interface transfer of the photogenerated electron and hole may be achieved simultaneously within the LPD-modified TiO₂ nanostructures because of the existence of the confined negative surface electrostatic field (NSEF) and the spatially oriented upward band bending (UBB). On the contrary, a homogeneous phosphate distribution (HPD) will greatly increase electron interface transfer resistance, which will cause the increase of recombination in bulk. The most important inspiration we can obtain herein is that a comprehensive consideration of the influence of nanostructure on all of the critical aspects of the carrier鈥檚 dynamics is needed during the rational design and construction of the advanced nanostructured photocatalyst systems. Considering the available resources for the synthesis and strong covalent interaction of phosphate with many other transition metal cations, the authors think that the novel strategy for a simultaneous optimization of the dynamic processes of the charge pairs by introducing LPD is promising for several applications including photocatalysis, photoelectrochemical hydrogen production, and solar cell.