This article reports a facile method for the colloidal synthesis of nanospheres made of amorphous selenium (ɑ-Se). The diameters of the nanospheres can be tightly controlled in the range of 45–157 nm by varying the reaction time and temperature, as well as the amount of the reducing agent. The average size of the nanospheres is measured using transmission electron microscopy and dynamic light scattering while their optical properties are characterized using UV-vis spectroscopy. We also compute their UV-vis spectra using the discrete dipole approximation (DDA) method and the calculated spectra are consistent with the experimental data based on the UV-vis spectra and the particle sizes derived from electron microscopy. The data derived from DDA calculations provides a fitting curve for finely controlling the sizes of the ɑ-Se nanospheres by monitoring the UV-vis spectra of the reaction solution at different stages of a synthesis.

中文翻译：

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无定形硒的胶体纳米球：简便的合成、尺寸控制和光学特性

本文报道了一种简便的胶体合成由非晶硒制成的纳米球的方法 ( ɑ-硒）。通过改变反应时间和温度以及还原剂的量，可以将纳米球的直径严格控制在 45-157 nm 范围内。使用透射电子显微镜和动态光散射测量纳米球的平均尺寸，同时使用紫外-可见光谱表征它们的光学特性。我们还使用离散偶极近似 (DDA) 方法计算了它们的紫外可见光谱，计算出的光谱与基于紫外可见光谱和电子显微镜得出的粒径的实验数据一致。从 DDA 计算得出的数据提供了一个拟合曲线，用于精细控制ɑ-通过在合成的不同阶段监测反应溶液的紫外-可见光谱来制备硒纳米球。