Al Amin Syed Muhammad, Kowser Md Arefin
Department of Nanomaterials and Ceramic Engineering, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh.
Department of Mechanical Engineering, Dhaka University of Engineering & Technology, Gazipur, Bangladesh.
Heliyon. 2024 Sep 6;10(18):e37558. doi: 10.1016/j.heliyon.2024.e37558. eCollection 2024 Sep 30.
Pure and Ag-doped Titanium dioxide (TiO) thin films have been synthesized via the sol-gel spin coating method, and their structural, morphological, and optical properties have been investigated. X-ray diffraction analysis verifies that the polycrystalline anatase TiO phase is retained up to 2 % Ag doping. However, lattice expansion and grain refinement down to 25.345 nm are observed with increasing Ag content. Scanning electron microscopy (SEM) reveals the formation of large, isolated TiO aggregates separated by drying-induced cracks across the film surface. Optical studies show the undoped TiO films demonstrate excellent visible transparency (>75 % transmittance) that slightly decreases upon Ag doping, though it remains suitably high for device applications. Meanwhile, optical absorption and defect states improve with more Ag incorporation, narrowing the TiO bandgap from 3.83 eV (undoped) to 3.51 eV (2 % Ag-doping) due to the incorporation of Ag-induced electronic states just below the conduction band minimum. The capability to control optical and structural properties through Ag doping highlights the potential of these TiO films suitably tailored for photovoltaic devices or self-cleaning coatings.
通过溶胶 - 凝胶旋涂法合成了纯的和掺银的二氧化钛（TiO₂）薄膜，并对其结构、形态和光学性质进行了研究。X射线衍射分析证实，多晶锐钛矿TiO₂相在银掺杂量高达2%时仍能保持。然而，随着银含量的增加，观察到晶格膨胀和晶粒细化至25.345纳米。扫描电子显微镜（SEM）显示，在整个薄膜表面形成了由干燥引起的裂纹分隔的大的、孤立的TiO₂聚集体。光学研究表明，未掺杂的TiO₂薄膜具有优异的可见光透明度（>75%的透过率），银掺杂后略有下降，不过对于器件应用来说仍保持在合适的高水平。同时，随着银掺入量的增加，光吸收和缺陷态得到改善，由于在导带最小值以下引入了银诱导的电子态，TiO₂的带隙从3.83电子伏特（未掺杂）缩小到3.51电子伏特（2%银掺杂）。通过银掺杂控制光学和结构性质的能力突出了这些TiO₂薄膜在光伏器件或自清洁涂层方面的潜在应用价值。
