Abstract Surface level sulphur (S) doped TiO2 nanorods (S-TNRs) were fabricated via toxic-free novel three-step processes such as low-temperature hydrothermal method followed by thermal evaporation (S layer) and post-annealing (350 °C, 450 °C and 550 °C) techniques. Present work focuses on the comprehensive studies of surface level doping, structure, morphology and compositional properties of different temperature annealed S-TNRs for CZTS thin-film (Au/CZTS/S-TNRs/TNRs/FTO) solar cells. The oxidation states of incorporated S atoms in the TiO2 matrix were identified from X-ray photoelector spectroscopy (XPS) analysis. A reduction in bandgap for 350 °C annealed S-TNRs film was observed from UV-Vis spectroscopy. The electrical characteristics showed the fabricated solar cells strongly depend on the S-TNRs annealing temperature. Proposed technique would be useful in effective and controlled (surface level) doping of S atoms into any desired nanostructured metal oxides for optoelectronic applications and, further useful in fabricating cadmium (Cd) free buffer layer in chalcogenide solar cells.

中文翻译：

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用于上层异质结 CZTS 薄膜太阳能电池的无毒表面级硫掺杂一维 Ti-Ox-Sy 纳米棒

摘要 表面级硫 (S) 掺杂的 TiO2 纳米棒 (S-TNRs) 通过无毒的新型三步法制备，例如低温水热法，然后热蒸发（S 层）和后退火（350 °C， 450 °C 和 550 °C) 技术。目前的工作重点是对用于 CZTS 薄膜（Au/CZTS/S-TNRs/TNRs/FTO）太阳能电池的不同温度退火 S-TNRs 的表面能级掺杂、结构、形貌和成分特性进行综合研究。TiO2 基质中掺入的 S 原子的氧化态通过 X 射线光电子能谱 (XPS) 分析确定。从 UV-Vis 光谱观察到 350°C 退火的 S-TNRs 薄膜的带隙减小。电气特性表明制造的太阳能电池强烈依赖于 S-TNRs 退火温度。