Electronic Structure, Optical Properties, and Photocatalytic Activities of LaFeO3鈥揘aTaO3 Solid Solution

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• 作者：Pushkar Kanhere ; Jawad Nisar ; Yuxin Tang ; Biswarup Pathak ; Rajeev Ahuja ; Jianwei Zheng ; Zhong Chen
• 刊名：The Journal of Physical Chemistry C
• 出版年：2012
• 出版时间：November 1, 2012
• 年：2012
• 卷：116
• 期：43
• 页码：22767-22773
• 全文大小：356K
• 年卷期：v.116,no.43(November 1, 2012)
• ISSN：1932-7455

文摘

A solid solution photocatalyst, Na_1鈥?i>xLa_xFe_1鈥?i>xTa_xO₃ (x up to 0.06), was prepared by the conventional solid-state method. The photophysical properties of the samples were studied by various experimental techniques and the electronic structures were investigated by using screened hybrid density functional (HSE06) calculations. The solid solution photocatalyst showed absorption of visible light extending up to 450 nm. Upon loading of platinum nanoparticles cocatalyst, the photocatalytic hydrogen evolution of 0.81 渭路mol路h^鈥?路g^鈥? was obtained for 2% doping of LaFeO₃ in NaTaO₃, under visible radiation (位 > 390 nm; 20% methanol solution). The photocatalytic properties of the solid solution were found to be better than Fe doped NaTaO₃ compounds on account of the suitable band structure. The electronic structure analysis revealed that, in the case of Fe doping at the Ta site, unoccupied electronic states in between the band gap appear that are responsible for the visible-light absorption. However, in the case of La and Fe codoping (passivated doping) the mid-gap electronic states are completely filled, which makes the band structure suitable for the visible-light photocatalysis. The present solid solution of perovskites (LaFeO₃ and NaTaO₃) sheds light on the interesting photophysical properties and photocatalytic activities which could be beneficial for the photocatalysts derived from these compounds.