Cadmium telluride (CdTe) thin films of different thicknesses deposited onto titanium dioxide (TiO₂) nanoparticle layer by spray pyrolysis deposition (SPD) are demonstrated as major photo-active semiconductor in photo-electrochemical solar cell configuration using iodide/triiodide (I⁻/I₃⁻) redox couple as a hole transport layer. The CdTe–TiO₂ heterogeneous films were characterized by X-ray photoelectron spectroscopy which identified doublet split of Cd 3d and Ti 2p which confirms CdTe and TiO₂. Optical absorbance and transmittance of CdTe and TiO₂ films which were examined by UV–Vis spectroscopy confirm that the optical bandgap of CdTe is 1.5 eV with a dominant photo-absorption in the spectral window of 350–800 nm, while TiO₂ showed a bandgap of 3.1 eV and is optically transparent in the visible spectral window. The present work examined photo-anodes comprising 1, 3, 5, and 10 SPD cycles of CdTe coated on TiO₂ nanoparticle layer. The solar cell with 5 SPD cycles of CdTe resulting in 0.4% efficiency. Results can be articulated to the CdTe deposited by 5 SPD cycles provided an optimum surface coverage in the bulk of TiO_2, while the higher SPD cycles leads to agglomeration which blocks the porosity of the heterogeneous films.

中文翻译：

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所有用于光电化学太阳能电池的热解喷涂CdTe–TiO 2异质膜

碲化镉（CdTe的）沉积到二氧化钛不同厚度的薄膜（氧化钛₂）通过喷雾热解沉积（SPD）纳米颗粒层使用证明是在光电化学太阳能电池结构的主要光活性半导体碘化物/三碘化物（I ^- / I ₃ ⁻）氧化还原对作为空穴传输层。通过X射线光电子能谱对CdTe-TiO ₂异质膜进行了表征，鉴定了Cd 3d和Ti 2p的双峰分裂，证实了CdTe和TiO ₂。CdTe和TiO _2的吸光率和透射率通过紫外-可见光谱检查的薄膜证实，CdTe的光学带隙为1.5 eV，在350-800 nm的光谱窗口中具有主要的光吸收，而TiO ₂的带隙为3.1 eV，并且在光学上是透明的。可见光谱窗口。本工作研究了包含1、2、3、5和10个SPD循环的CdTe涂覆在TiO ₂纳米颗粒层上的光阳极。具有5个SPD循环的CdTe的太阳能电池，效率为0.4％。可以通过5个SPD循环将结果清楚地表示为CdTe沉积，从而在大部分TiO _2中提供了最佳的表面覆盖率_，而更高的SPD循环会导致团聚，从而阻止了异质膜的孔隙率。