Zhou Jingjian, Huang Jing, Chen Huai, Samanta Archana, Linnros Jan, Yang Zhenyu, Sychugov Ilya
Department of Applied Physics, KTH - Royal Institute of Technology, Stockholm 10691, Sweden.
MOE Laboratory of Bioinorganic and Synthetic Chemistry, Lehn Institute of Functional Materials, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, Guangdong China.
J Phys Chem Lett. 2021 Sep 23;12(37):8909-8916. doi: 10.1021/acs.jpclett.1c02187. Epub 2021 Sep 9.
As a cost-effective batch synthesis method, Si quantum dots (QDs) with near-infrared photoluminescence, high quantum yield (>50% in polymer nanocomposite), and near-unity internal quantum efficiency were fabricated from an inexpensive commercial precursor (triethoxysilane, TES), using optimized annealing and etching processes. The optical properties of such QDs are similar to those prepared from state-of-the-art precursors (hydrogen silsesquioxane, HSQ) yet featuring an order of magnitude lower cost. To understand the effect of synthesis parameters on QD optical properties, we conducted a thorough comparison study between common solid precursors: TES, HSQ, and silicon monoxide (SiO), including chemical, structural, and optical characterizations. We found that the structural nonuniformity and abundance of oxide inherent to SiO limited the resultant QD performance, while for TES-derived QDs this drawback can be avoided. The presented low-cost synthetic approach would significantly favor applications requiring high loading of good-quality Si QDs, such as light conversion for photovoltaics.
作为一种经济高效的批量合成方法，使用优化的退火和蚀刻工艺，由廉价的商业前驱体（三乙氧基硅烷，TES）制备出具有近红外光致发光、高量子产率（在聚合物纳米复合材料中>50%）和近乎单位内量子效率的硅量子点（QDs）。此类量子点的光学性质与由最先进的前驱体（氢倍半硅氧烷，HSQ）制备的量子点相似，但成本低一个数量级。为了解合成参数对量子点光学性质的影响，我们对常见的固体前驱体：TES、HSQ和一氧化硅（SiO）进行了全面的比较研究，包括化学、结构和光学表征。我们发现，SiO固有的结构不均匀性和氧化物丰度限制了所得量子点的性能，而对于TES衍生的量子点，这一缺点可以避免。所提出的低成本合成方法将极大地有利于需要高负载高质量硅量子点的应用，如用于光伏的光转换。
