School of Pharmacy and Biomedical Sciences, University of Central Lancashire, Preston, PR12HE, UK.
UCLan Research Centre for Smart Materials, School of Natural Sciences, Preston, PR12HE, UK.
Sci Rep. 2021 May 18;11(1):10554. doi: 10.1038/s41598-021-89984-w.
In this study we demonstrate simple guidelines to generate a diverse range of fluorescent materials in both liquid and solid state by focusing on the most popular C-dots precursors, i.e. the binary systems of citric acid and urea. The pyrolytic treatment of those precursors combined with standard size separation techniques (dialysis and filtration), leads to four distinct families of photoluminescent materials in which the emissive signal predominantly arises from C-dots with embedded fluorophores, cyanuric acid-rich C-dots, a blend of molecular fluorophores and a mixture of C-dots with unbound molecular fluorophores, respectively. Within each one of those families the chemical composition and the optical properties of their members can be fine-tuned by adjusting the molar ratio of the reactants. Apart from generating a variety of aqueous dispersions, our approach leads to highly fluorescent powders derived from precursors comprising excessive amounts of urea that is consumed for the build-up of the carbogenic cores, the molecular fluorophores and the solid diluent matrix that suppresses self-quenching effects.
在这项研究中,我们通过聚焦于最受欢迎的 C 点前体,即柠檬酸和尿素的二元体系,展示了在液态和固态下生成多种荧光材料的简单指南。这些前体的热解处理与标准尺寸分离技术(透析和过滤)相结合,导致了四种不同的光致发光材料家族,其中发射信号主要来自于嵌入荧光团的 C 点、富氰尿酸的 C 点、分子荧光团的混合物和未结合的分子荧光团的混合物的 C 点。在这些家族中的每一个家族中,通过调整反应物的摩尔比,可以精细调整其成员的化学组成和光学性质。除了生成各种水基分散体之外,我们的方法还导致了源自包含过量尿素的前体的高荧光粉末,尿素用于构建碳核、分子荧光团和抑制自猝灭效应的固体稀释剂基质。