A facile and eco-friendly hydrothermal method was used to prepare carbon quantum dots (CQDs) using orange waste peels. The synthesized CQDs were well dispersed and the average diameter was 2.9 ± 0.5 nm. Functional group identification of the CQDs was confirmed by Fourier transform infrared spectrum analysis. Fluorescence properties of the synthesized CQDs exhibited blue emission. The fluorescence quantum yield of the CQDs was around 11.37% at an excitation wavelength of 330 nm. The higher order nonlinear optical properties were examined using a Z-scan technique and a continuous wave laser that was operated at a wavelength of 532 nm. Results demonstrated that the synthesis of CQDs can be considered as promising for optical switching devices, bio-scanning, and bio-imaging for optoelectronic applications.

中文翻译：

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从橙色废皮中轻松制备高荧光碳量子点，用于非线性光学应用。

一种简便且生态友好的水热法被用于使用橙皮来制备碳量子点（CQD）。合成的CQD分散良好，平均直径为2.9±0.5 nm。通过傅立叶变换红外光谱分析确认了CQD的官能团鉴定。合成的CQD的荧光性质显示出蓝色发射。在330nm的激发波长下，CQD的荧光量子产率约为11.37％。使用Z扫描技术和在532 nm波长下操作的连续波激光器检查了更高阶的非线性光学特性。结果表明，CQD的合成可用于光开关设备，生物扫描和光电成像的生物成像。