Photochemical Properties, Composition, and Structure in Molecular Beam Epitaxy Grown Fe “Doped” and (Fe,N) Codoped Rutile TiO2(110)
Photochemical Properties, Composition, and Structure in Molecular Beam Epitaxy Grown Fe “Doped” and (Fe,N) Codoped Rutile TiO2(110)
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DOI：
10.1021/jp203061n
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发表时间：
2011-07
影响因子：
3.7
通讯作者：
Andrew N. Mangham;N. Govind;M. Bowden;V. Shutthanandan;A. Joly;M. A. Henderson;S. Chambers
中科院分区：
文献类型：
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作者：
Andrew N. Mangham;N. Govind;M. Bowden;V. Shutthanandan;A. Joly;M. A. Henderson;S. Chambers
研究了等离子体辅助分子束外延生长的Fe“掺杂”和（Fe，N）共掺杂同质外延金红石型TiO 2（110）薄膜的表面光化学性质。Fe不作为电子掺杂剂并入金红石晶格中，而是分离到膜表面。然而，铁与N的共沉积增强了铁的溶解度，DFT计算表明，共掺杂络合物的形成是增强的溶解度背后的驱动力。共掺杂的薄膜，其中几个原子百分比的Ti（O）被替换为Fe（N），表现出显着的无序相比，在相同的条件下生长的未掺杂的薄膜，大概是由于掺杂剂诱导的应变。共掺杂使金红石带隙红移到可见光。然而，膜表面是光化学惰性的空穴介导的分解吸附的乙酸三甲酯。光化学活性的缺乏可能是由膜内的掺杂剂诱导的陷阱和/或重组位点引起的。这项研究表明，增强…
We have investigated the surface photochemical properties of Fe “doped” and (Fe,N) codoped homoepitaxial rutile TiO2(110) films grown by plasma-assisted molecular beam epitaxy. Fe does not incorporate as an electronic dopant in the rutile lattice but rather segregates to the film surface. However, codeposition of Fe with N enhances the solubility of Fe, and DFT calculations suggest that codopant complex formation is the driving force behind the enhanced solubility. The codoped films, in which a few atomic percent of Ti (O) are replaced with Fe (N), exhibit significant disorder compared to undoped films grown under the same conditions, presumably due to dopant-induced strain. Codoping redshifts the rutile bandgap into the visible. However, the film surfaces are photochemically inert with respect to hole-mediated decomposition of adsorbed trimethyl acetate. The absence of photochemical activity may result from dopant-induced trap and/or recombination sites within the film. This study indicates that enhanced...