Cadmium selenide (CdSe) nanoparticles dispersed in the PVP matrix with varying concentrations of cadmium (Cd) ion complex have been synthesized through a low-cost chemical bath deposition technique to investigate the effects of cadmium ion concentration on its optical and photo-response characteristics. To confirm the formation of pure, stable, well dispersed, and highly crystalline spherical CdSe nanocomposites different characterization techniques such as X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and Fourier transform infrared spectroscopy have been used. The optical band gaps and sizes of the nanocomposites are determined from the UV–Vis data while the surface-related emission properties of the CdSe nanocomposites are obtained from the PL data. The quantum confinement on the CdSe nanocomposites increases with the decrease of Cd ion concentration. I–V characteristics measurements have been done on the samples to investigate the photo-response properties of the samples. Various optical properties such as bandgap, near bandgap emission, and impurity emission are correlated with the photo-response properties of the samples. The photoresponse properties are found to become more suitable for application in white light photosensor with the increase of quantum confinement. Mechanisms related to the enhancement of photocurrent with respect to quantum confinement are also discussed in this paper.

中文翻译：

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镉离子浓度对用于白光传感应用的 CdSe/PVP 纳米复合材料的光学和光响应特性的影响

已经通过低成本化学浴沉积技术合成了分散在 PVP 基质中的硒化镉 (CdSe) 纳米粒子，具有不同浓度的镉 (Cd) 离子复合物，以研究镉离子浓度对其光学和光响应特性的影响。为了确认纯、稳定、分散良好和高度结晶的球形 CdSe 纳米复合材料的形成，使用了不同的表征技术，如 X 射线衍射、场发射扫描电子显微镜、高分辨率透射电子显微镜和傅里叶变换红外光谱。纳米复合材料的光学带隙和尺寸由 UV-Vis 数据确定，而 CdSe 纳米复合材料的表面相关发射特性由 PL 数据获得。CdSe 纳米复合材料的量子限制随着 Cd 离子浓度的降低而增加。已经对样品进行了 I-V 特性测量，以研究样品的光响应特性。各种光学特性，如带隙、近带隙发射和杂质发射，都与样品的光响应特性相关。发现随着量子限制的增加，光响应特性变得更适合在白光光电传感器中的应用。本文还讨论了与量子限制相关的光电流增强相关的机制。各种光学特性，如带隙、近带隙发射和杂质发射，都与样品的光响应特性相关。发现随着量子限制的增加，光响应特性变得更适合在白光光电传感器中的应用。本文还讨论了与量子限制相关的光电流增强相关的机制。各种光学特性，如带隙、近带隙发射和杂质发射，都与样品的光响应特性相关。发现随着量子限制的增加，光响应特性变得更适合在白光光电传感器中的应用。本文还讨论了与量子限制相关的光电流增强相关的机制。