Recently, natural products are the powerful carbon source to synthesize carbon dots (CDs) with interesting physical and chemical properties. In this present work, we report a facile hydrothermal synthesis method for preparing fluorescent carbon dots using a biogenic precursor of rice bran without any surface passivation agent. The synthetic methodology was easy, simple, environmental friendly and convenient. Structural and optical properties of the RB-CDs have been studied by UV-visible, Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM), Fluorescence spectra and X-ray photoelectron spectroscopy (XPS) techniques. The prepared RB-CDs exhibited green emission upon irradiation with UV light and the calculated fluorescence quantum yield (QY) was found to be 7.4%. The morphological features of the synthesized RB-CDs were characterized by High-Resolution Transmission Electron Microscopy (HR-TEM), the average size of the RB-CDs was found to be 2.96 nm. The synthesized RB-CDs were beneficially applied as a catalyst for the catalytic degradation of methylene blue (MB) dye using NaBH₄ as the reducing agent in the ambient conditions. The degradation of MB dye under light illumination was 89.20% in 30 min. Further, the obtained highly fluorescent RB-CDs were efficiently utilized as a fluorescent ink for luminescent pattern printing (patterning agent) in the anti-counterfeiting applications.

最近，天然产物是合成具有有趣物理和化学性质的碳点 (CD) 的强大碳源。在目前的工作中，我们报告了一种简便的水热合成方法，该方法使用米糠的生物前体制备荧光碳点，无需任何表面钝化剂。该合成方法简单、环保、方便。RB-CD 的结构和光学特性已通过紫外-可见光、傅里叶变换红外光谱 (FTIR)、场发射扫描电子显微镜 (FESEM)、荧光光谱和 X 射线光电子能谱 (XPS) 技术进行了研究。制备的 RB-CD 在紫外光照射下表现出绿色发射，计算出的荧光量子产率 (QY) 为 7.4%。合成的 RB-CDs 的形态特征通过高分辨率透射电子显微镜 (HR-TEM) 进行表征, 发现 RB-CDs 的平均尺寸为 2.96 nm。合成的 RB-CDs 有益地用作使用 NaBH 催化降解亚甲蓝 (MB) 染料的催化剂₄在环境条件下作为还原剂。MB染料在光照下30分钟降解率为89.20%。此外，所获得的高荧光 RB-CDs 被有效地用作防伪应用中用于发光图案印刷（图案化剂）的荧光油墨。