Gharibshahi Elham, Radiman Shahidan, Ashraf Ahmadreza, Saion Elias, Gharibshahi Leila, Ashraf Sina
Department of Electrical and Computer Engineering, University of Texas at San Antonio (UTSA), One UTSA Circle, San Antonio, TX 78249, USA.
School of Applied Physics, Faculty of Science and Technology, National University of Malaysia (UKM), UKM Bangi, Selangor 43600, Malaysia.
Micromachines (Basel). 2023 Jul 6;14(7):1383. doi: 10.3390/mi14071383.
Cobalt nanoparticles were synthesized using the gamma radiolytic technique, and the particle size was found to be reduced from 12±1 to 7±1 nm by increasing the dose from 10 to 60 kGy. The UV-visible absorption spectra were measured and exhibited a steady absorption maxima at 517 nm in the UV region, which blue-shifted toward a lower wavelength with a decrease in particle size. By taking the conduction electrons of an isolated particle that are not entirely free but are instead bound to their respective quantum levels, the optical absorption of the cobalt nanoparticles can be calculated and simulated via intra-band quantum excitation for particle sizes comparable to the measured ones. We found that the simulated absorption maxima of electronic excitations corresponded to the measured absorption maxima. Moreover, the structural characterizations were performed utilizing dynamic light scattering (DLS), transmission electron microscopy (TEM), and X-ray diffraction (XRD).
采用γ辐射分解技术合成了钴纳米颗粒，发现通过将剂量从10 kGy增加到60 kGy，粒径从12±1 nm减小到7±1 nm。测量了紫外可见吸收光谱，在紫外区域517 nm处呈现出稳定的吸收最大值，随着粒径减小，该最大值向较低波长蓝移。通过考虑孤立颗粒的传导电子并非完全自由而是束缚在各自的量子能级上，对于与测量尺寸相当的粒径，可以通过带内量子激发来计算和模拟钴纳米颗粒的光吸收。我们发现电子激发的模拟吸收最大值与测量的吸收最大值相对应。此外，利用动态光散射（DLS）、透射电子显微镜（TEM）和X射线衍射（XRD）进行了结构表征。
