Enhanced photoelectrochemical and photocatalytic behaviors of MFe2O4 (M = Ni, Co, Zn and Sr) modified TiO2 nanorod arrays.
Enhanced photoelectrochemical and photocatalytic behaviors of MFe2O4 (M = Ni, Co, Zn and Sr) modified TiO2 nanorod arrays.
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DOI：
10.1038/srep30543
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发表时间：
2016-07-28
影响因子：
4.6
通讯作者：
Xie Z
中科院分区：
文献类型：
--
作者：
Gao X;Liu X;Zhu Z;Wang X;Xie Z
改性TiO 2纳米材料被认为在能量转换方面具有很好的应用前景，而铁氧体改性可能是最有效的改性方法之一。在本研究中，不同的铁氧体，掺入不同的阳离子（MFe 2 O 4，M = Ni，Co，Zn和Sr），用于改性的TiO 2纳米棒阵列（NRA），这是通过水热法合成的。结果表明，与TiO 2纳米光催化剂相比，MFe 2 O 4/TiO 2纳米光催化剂的光致发光光谱均发生了明显的红移。特别是，NiFe 2 O 4改性被证明是最好的方式，以提高光电化学和光催化活性的TiO 2 NRA。此外，通过电化学阻抗谱测量，澄清了MFe 2 O 4改性后的电荷载流子的分离和转移。最后，提出了MFe 2 O 4/TiO 2 NRA光催化活性增强的机理。通过对不同过渡金属改性TiO 2在相同合成工艺和评价条件下的比较，为设计具有可见光活性的改性TiO 2纳米材料提供了新的思路。
Modified TiO2 nanomaterials are considered to be promising in energy conversion and ferrites modification may be one of the most efficient modifications. In this research, various ferrites, incorporated with various cations (MFe2O4, M = Ni, Co, Zn, and Sr), are utilized to modify the well aligned TiO2 nanorod arrays (NRAs), which is synthesized by hydrothermal method. It is found that all MFe2O4/TiO2 NRAs show obvious red shift into the visible light region compared with the TiO2 NRAs. In particular, NiFe2O4 modification is demonstrated to be the best way to enhance the photoelectrochemical and photocatalytic activity of TiO2 NRAs. Furthermore, the separation and transfer of charge carriers after MFe2O4 modification are clarified by electrochemical impedance spectroscopy measurements. Finally, the underlying mechanism accounting for the enhanced photocatalytic activity of MFe2O4/TiO2 NRAs is proposed. Through comparison among different transition metals modified TiO2 with the same synthesis process and under the same evaluating condition, this work may provide new insight in designing modified TiO2 nanomaterials as visible light active photocatalysts.