Abstract Ho doped Ag2S thin films were grown on the glass substrate by chemical bath deposition (CBD) method at room temperature. The bath contained aqueous solution of silver nitrate, thiourea, EDTA, ammonia and holmium nitrate. Silver nitrate was used as a silver (Ag+) ion source; thiourea as sulfur (S−) ion source, EDTA was a complexing agent while ammonia was used to maintain pH, Ho(NO3)3 was taken as a source of Ho ions. The optical absorption edge of undoped (pure) and Ho doped silver sulfide films was determined between 324 nm and 298 nm showing blue shift as compared to bulk Ag2S. Band gaps calculated from Tauc plot also showed an increase in values for doped samples. The increase in band gap indicates reduced particle size in the prepared Ho doped films. The photoluminescence emission peaks were observed at around 578 nm to 601 nm wavelength and excitation peaks were found at 351 nm to 294 nm for undoped and doped films. The SEM micrograph consists of globular ball type and flower type structures observed in the prepared films of Ho doped Ag2S.

中文翻译：

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CBD法制备Ho掺杂Ag2S薄膜的研究

摘要 通过化学浴沉积（CBD）方法在室温下在玻璃基板上生长了掺 Ho 的 Ag2S 薄膜。该浴包含硝酸银、硫脲、EDTA、氨和硝酸钬的水溶液。硝酸银用作银 (Ag+) 离子源；硫脲作为硫 (S-) 离子源，EDTA 是络合剂，而氨用于维持 pH 值，Ho(NO3)3 作为 Ho 离子源。在 324 nm 和 298 nm 之间测定未掺杂（纯）和 Ho 掺杂的硫化银薄膜的光学吸收边，与块状 Ag2S 相比，显示蓝移。从 Tauc 图计算的带隙也显示掺杂样品的值增加。带隙的增加表明制备的 Ho 掺杂薄膜的粒径减小。对于未掺杂和掺杂的薄膜，在 578 nm 至 601 nm 波长附近观察到光致发光发射峰，在 351 nm 至 294 nm 处发现激发峰。SEM 显微照片由在制备的 Ho 掺杂 Ag2S 薄膜中观察到的球状和花状结构组成。