球粒状和棒状纳米赤铁矿光电化学特性研究

发布时间：2018-06-17 17:52

  本文选题：赤铁矿 + 形貌　； 参考：《岩石矿物学杂志》2017年06期

【摘要】：本文以乙二醇为诱导剂通过电化学沉积法成功合成了球粒状及棒状纳米赤铁矿。X射线衍射光谱(XRD)和Raman光谱结果表明,球粒状赤铁矿粒径20±5 nm;棒状赤铁矿截面直径约20 nm,长90±10 nm;二者物相皆为单一均匀的赤铁矿。紫外-可见吸收光谱显示两种赤铁矿在300~550 nm范围内均有较好吸收,Tauc方程计算球粒状和棒状赤铁矿禁带宽度分别为2.00 e V和1.99 e V。Mott-Schottky拟合结果表明1 M KOH溶液体系中,棒状赤铁矿载流子浓度为1.95×1021cm-3,高于球粒状赤铁矿(3.16×1020cm-3)。进一步的光电化学实验表明:0.6 V(vs.Ag/Ag Cl)电势下棒状赤铁矿光照下电流密度较暗电流提升550%,球粒状赤铁矿电流密度提升77%。研究证实,赤铁矿形貌对其半导体特性及光电化学特性有影响,且棒状赤铁矿电极表现出更好的可见光响应特性,具有更佳的光电催化潜力。
[Abstract]:In this paper, the spherical and rod-shaped nanocrystalline hematite were successfully synthesized by electrochemical deposition with ethylene glycol as inducer. The diameter of globular hematite is 20 卤5 nm, the section diameter of rod-shaped hematite is about 20 nm and the length of hematite is 90 卤10 nm. The UV-Vis absorption spectra show that both kinds of hematite have better absorption in the range of 300 ~ 550 nm. The calculated bandgap width of spherical hematite and rod-shaped hematite is 2.00 EV and 1.99 e V. Mott-Schottky fitting results, respectively. The results show that in the system of 1M Koh solution, the band gap of hematite is 2.00 EV and 1.99 e V. Mott-Schottky, respectively. The carrier concentration of rod-shaped hematite is 1.95 脳 1021cm-3, which is higher than that of globular hematite (3.16 脳 1020cm-3). Further photochemical experiments show that the current density of rod-shaped hematite increases by 550 and that of globular hematite increases by 77. The results show that the morphology of hematite has an effect on the semiconductor and photochemical properties of hematite, and the rod hematite electrode has better visible light response and better photocatalytic potential.
【作者单位】： 造山带与地壳演化教育部重点实验室矿物环境功能北京市重点实验室北京大学地球与空间科学学院;
【基金】：国家重点基础研究发展计划“973计划”(2014CB846001) 国家自然科学基金(41230103,41522201) 博士后基金(2014M550552)~~
【分类号】：P579;X505
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本文编号：2031932