【摘要】 采用溶胶-凝胶法在纯钛基体上制备Zn掺杂纳米TiO₂薄膜（Zn-TiO₂）,研究不同热处理温度下Zn掺杂对纳米TiO₂薄膜的物理性能、光阴极保护效果和光电化学性能的影响。研究表明,与未掺杂TiO₂薄膜相比,Zn的加入提高了Zn-TiO₂薄膜的光电化学响应,在300°C热处理后的薄膜使金属基体的电极电位下降最大,降低了897 mV。SEM-EDS分析表明,Zn在掺杂薄膜中的分布不均匀,XRD结果显示Zn掺杂的薄膜比未掺杂的薄膜晶粒更细小。红外光谱结果表明,TiO₂晶粒表面有Zn—O键生成。紫外光谱表明,Zn掺杂使Zn-TiO 2吸收带边红移,扩大了TiO 2的光响应范围。根据Mott-Shottky曲线可知,Zn-TiO₂薄膜比纯TiO₂薄膜的平带电位更负,载流子量更大。这说明在平带电位、载流子量和空间电荷层宽度的协同作用下,300°C热处理后的Zn-TiO₂薄膜表现了最佳的光电化学响应。更多还原

【Abstract】 Zn-doped TiO₂（Zn-TiO₂） thin films were prepared by the sol-gel method on titanium substrates with heat treatment at different temperatures. The effects of heat treatment temperatures and Zn doping on the structure, photocathodic protection and photoelectrochemical properties of TiO₂ thin films were investigated. It is indicated that the photoelectrical performance of the Zn-TiO₂ films is enhanced with the addition of Zn element compared with the pure-TiO₂ film and the largest decline by 897 m V in the electrode potential is achieved under 300 °C heat treatment. SEM-EDS analyses show that Zn element is unevenly distributed in Zn-TiO₂ films; XRD patterns reveal that the grain size of Zn-TiO₂ is smaller than that of pure-TiO₂; FTIR results indicate that Zn—O bond forms on Zn-TiO₂ surface. Ultraviolet visible absorption spectra prove that Zn-TiO₂ shifts to visible light region. Mott-Shottky curves show that the flat-band potential of Zn-TiO₂ is more negative and charge carrier density is bigger than that of pure-TiO₂, implying that under the synergy of the width of the space-charge layer, carrier density and flat-band potential, Zn-TiO₂ with 300 °C heat treatment displays the best photocathodic protection performance.更多还原