Mura Stefania, Ludmerczki Róbert, Stagi Luigi, Garroni Sebastiano, Carbonaro Carlo Maria, Ricci Pier Carlo, Casula Maria Francesca, Malfatti Luca, Innocenzi Plinio
Laboratory of Materials Science and Nanotechnology, CR-INSTM, Department of Chemistry and Pharmacy, University of Sassari, Via Vienna 2, 07100, Sassari, Italy.
Department of Chemistry and Pharmacy, University of Sassari, Via Vienna 2, 07100, Sassari, Italy.
Sci Rep. 2020 Mar 16;10(1):4770. doi: 10.1038/s41598-020-61517-x.
Highly fluorescent blue and green-emitting carbon dots have been designed to be integrated into sol-gel processing of hybrid organic-inorganic materials through surface modification with an organosilane, 3-(aminopropyl)triethoxysilane (APTES). The carbon dots have been synthesised using citric acid and urea as precursors; the intense fluorescence exhibited by the nanoparticles, among the highest reported in the scientific literature, has been stabilised against quenching by APTES. When the modification is carried out in an aqueous solution, it leads to the formation of silica around the C-dots and an increase of luminescence, but also to the formation of large clusters which do not allow the deposition of optically transparent films. On the contrary, when the C-dots are modified in ethanol, the APTES improves the stability in the precursor sol even if any passivating thin silica shell does not form. Hybrid films containing APTES-functionalized C-dots are transparent with no traces of C-dots aggregation and show an intense luminescence in the blue and green range.
通过用有机硅烷3-(氨丙基)三乙氧基硅烷（APTES）进行表面改性，已设计出高荧光蓝色和绿色发光碳点，以便将其整合到有机-无机杂化材料的溶胶-凝胶加工过程中。碳点是使用柠檬酸和尿素作为前体合成的；纳米颗粒所表现出的强烈荧光，是科学文献中报道的最高荧光之一，已通过APTES稳定下来，防止猝灭。当在水溶液中进行改性时，会导致在碳点周围形成二氧化硅并增加发光，但也会形成大的聚集体，从而无法沉积光学透明薄膜。相反，当在乙醇中对碳点进行改性时，即使没有形成任何钝化的二氧化硅薄壳，APTES也能提高前体溶胶中的稳定性。含有APTES功能化碳点的杂化薄膜是透明的，没有碳点聚集的痕迹，并在蓝色和绿色范围内显示出强烈的发光。
