Abstract This contribution reports for the first time, room temperature biosynthesis of p-type CuO nanoparticles carried out using Callistemon viminalis’ flower extracts as a chelating agent in a process that is entirely green. Room temperature X-ray diffraction, attenuated IR total reflection spectroscopy, X-ray photoelectron and Raman spectroscopy investigations confirmed the formation of single phase Tenorite bcc monoclinic CuO nanocrystals post annealing in air, at 500 °C. Photoluminescence spectroscopy with UV emissions at 356 nm (3.47 eV) and broad visible emissions at 418 nm, 561 nm, and 664 nm, support the formation in air, at 200 °C, of CuO nanoparticles with high surface-to-volume ratios and defects. As a direct application, the biosynthesized CuO nanoplatelet-containing powder dispersed in de-ionized water showed an enhancement of the thermal conductivity from 6% to 34% and a significant stability of the PVP stabilized CuO-water nanofluid.

中文翻译：

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生物合成的 CuO 纳米片：物理特性和增强的导热性纳米流体

摘要 本论文首次报道了在完全绿色的过程中使用 Callistemon viminalis 的花提取物作为螯合剂进行 p 型 CuO 纳米颗粒的室温生物合成。室温 X 射线衍射、衰减红外全反射光谱、X 射线光电子和拉曼光谱研究证实了单相 Tenorite bcc 单斜 CuO 纳米晶体在空气中 500 °C 退火后的形成。具有 356 nm (3.47 eV) 紫外发射和 418 nm、561 nm 和 664 nm 宽可见光发射的光致发光光谱支持在 200 °C 的空气中形成具有高表面积与体积比的 CuO 纳米粒子和缺陷。作为直接应用，