Abstract Earth abundant, nontoxic Cu2SnS3 (CTS) thin films are prepared using low-cost ultrasonic spray pyrolysis (USP) technique by varying different copper (Cu) precursor (copper chloride) concentration. Influence of Cu concentration on the electrical, optical and structural properties of CTS thin films are studied. XRD, TEM results confirm the formation of tetragonal structure of CTS films with orientation along (112) plane. Raman analysis reconfirms the tetragonal structure of CTS thin film and Cu2S secondary phase in films with higher Cu concentration samples. Stoichiometric film is found for 0.025M Cu concentration. XPS and PL studies are also performed. The absorption coefficient of CTS films is found to be ~105 cm−1 and optical bandgap is varying from 1.32 eV to 1.49 eV. P-type semiconductor nature of the film is found from electrical characteristics with carrier concentration of ~1021/cm3. The resistivity of the film decreases from 4.6 × 10−1 to 9.5 × 10−4 Ω-cm as Cu concentration increases. These properties are suitable for solar cell absorber layer. The optimized CTS thin film is used as a photocatalyst and photocatalysis activity of methylene blue (MB) dye is examined under visible light irradiation. A significant photodegradation (~90%) of MB achieved under 3 h visible light irradiation.

中文翻译：

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铜浓度对用于太阳能电池吸收层和光催化应用的 CTS 薄膜的影响

摘要 使用低成本超声喷雾热解 (USP) 技术，通过改变不同的铜 (Cu) 前驱体（氯化铜）浓度，制备了地球丰富、无毒的 Cu2SnS3 (CTS) 薄膜。研究了Cu浓度对CTS薄膜的电学、光学和结构特性的影响。XRD、TEM 结果证实了沿 (112) 面取向的 CTS 薄膜的四方结构的形成。拉曼分析再次确认了 CTS 薄膜的四方结构和具有较高 Cu 浓度样品的薄膜中的 Cu2S 次生相。发现 0.025M 铜浓度的化学计量薄膜。还进行了 XPS 和 PL 研究。发现 CTS 薄膜的吸收系数约为 105 cm-1，光学带隙从 1.32 eV 变化到 1.49 eV。该薄膜的 P 型半导体性质是从载流子浓度约为 1021/cm3 的电特性中发现的。随着 Cu 浓度的增加，薄膜的电阻率从 4.6 × 10-1 降低到 9.5 × 10-4 Ω-cm。这些特性适用于太阳能电池吸收层。优化的 CTS 薄膜用作光催化剂，并在可见光照射下检查亚甲基蓝 (MB) 染料的光催化活性。在 3 小时可见光照射下实现了显着的 MB 光降解（~90%）。优化的 CTS 薄膜用作光催化剂，并在可见光照射下检查亚甲基蓝 (MB) 染料的光催化活性。在 3 小时可见光照射下实现了显着的 MB 光降解（~90%）。优化的 CTS 薄膜用作光催化剂，并在可见光照射下检查亚甲基蓝 (MB) 染料的光催化活性。在 3 小时可见光照射下实现了显着的 MB 光降解（~90%）。