Raju Ganji Seeta Rama, Varaprasad Ganji Lakshmi, Lee Jeong-Hwan, Park Jin Young, Chodankar Nilesh R, Ranjith Kugalur Shanmugam, Pavitra Eluri, Huh Yun Suk, Han Young-Kyu
Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul 04620, Korea.
Department of Biological Engineering, Biohybrid Systems Research Center (BSRC), Inha University, Incheon 22212, Korea.
Nanomaterials (Basel). 2022 Aug 19;12(16):2864. doi: 10.3390/nano12162864.
Quantum dots (QDs) have an unparalleled ability to mimic true colors due to their size-tunable optical and electronic properties, which make them the most promising nanoparticles in various fields. Currently, the majority of QDs available in the market are cadmium, indium, and lead-based materials but the toxicity and unstable nature of these QDs restricts their industrial and practical applications. To avoid using heavy metal ions, especially cadmium, the current research is focused on the fabrication of perovskite and vanadate QDs. Herein, we report the facile synthesis of a novel and cost-effective CsVO QDs for the first time. The sizes of the CsVO QDs produced were tuned from 2 to 10 nm by varying the reaction temperature from 140 to 190 °C. On increasing QD size, a continuous red shift was observed in absorption and emission spectra, signifying the presence of quantum confinement. In addition, along with CsVO QDs, the CsVO nanosheets self-assembled microflower-like particles were found as residue after the centrifugation; the X-ray diffraction indicated an orthorhombic structure. Under 365 nm excitation, these CsVO microflower-like particles exhibited broad emission with CIE coordinates in the white emission region. The acquired results suggest that CsVO QDs may represent a new class of cadmium-free materials for optoelectronic and biomedical applications.
量子点（QDs）由于其尺寸可调的光学和电子特性，具有无与伦比的模拟真彩色的能力，这使其成为各个领域中最有前途的纳米粒子。目前，市场上大多数可用的量子点是镉、铟和铅基材料，但这些量子点的毒性和不稳定性质限制了它们的工业和实际应用。为了避免使用重金属离子，特别是镉，当前的研究集中在钙钛矿和钒酸盐量子点的制备上。在此，我们首次报道了一种新型且具有成本效益的CsVO量子点的简便合成方法。通过将反应温度从140℃变化到190℃，所制备的CsVO量子点的尺寸从2纳米调整到10纳米。随着量子点尺寸的增加，在吸收光谱和发射光谱中观察到连续的红移，这表明存在量子限域效应。此外，除了CsVO量子点外，在离心后发现CsVO纳米片自组装成微花状颗粒作为残留物；X射线衍射表明其为正交结构。在365纳米激发下，这些CsVO微花状颗粒在白色发射区域呈现出具有CIE坐标的宽发射。所获得的结果表明，CsVO量子点可能代表了一类用于光电子和生物医学应用的新型无镉材料。
