Silicene Quantum Dots: Synthesis, Spectroscopy, and Electrochemical Studies
Silicene Quantum Dots: Synthesis, Spectroscopy, and Electrochemical Studies
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DOI：
10.1021/acs.langmuir.7b04253
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发表时间：
2018-02-27
期刊：
影响因子：
3.9
通讯作者：
Chen, Shaowei
中科院分区：
文献类型：
--
作者：
Hu, Peiguang;Chen, Limei;Chen, Shaowei
采用化学剥离法合成了有机硅量子点，并通过与烯烃/乙炔衍生物的硅氢化反应形成Si-CH_2-CH_2或Si-CH=CH-界面键进行稳定化。透射电子显微镜和原子力显微镜的测量结果表明，所得的量子点是约。直径约2nm，由约1000个纳米颗粒组成。四层硅原子层通过H-1和Si-29 NMR和X射线光电子能谱测量进一步表征了结构。在光致发光测量中，SiQDs在385 nm处表现出较强的发射，并且强度随界面连接而变化。在电化学测试中，乙炔基二茂铁和乙烯基二茂铁功能化的SiQDs在黑暗中在+0.15V（vsFc（+）/Fc）处表现出一对明确的伏安峰，用于二茂铁/二茂铁对的氧化还原反应;而在紫外光照射下，在-0.41V处出现另外一对伏安峰，最有可能是因为从SiQD到二茂铁金属中心的光诱导电子转移所形成的二茂铁阴离子的氧化还原反应。
Organically functionalized silicene quantum dots (SiQDs) were synthesized by chemical exfoliation of calcium silicide and stabilized by hydrosilylation with olefin/acetylene derivatives forming Si-CH2-CH2 or Si-CH=CH- interfacial bonds. Transmission electron microscopy and atomic force microscopy measurements showed that the resultant SiQDs were ca. 2 nm in diameter and consisted of ca. four atomic layers of silicon. The structure was further characterized by H-1 and Si-29 NMR and X-ray photoelectron spectroscopic measurements. In photoluminescence measurements, the SiQDs exhibited a strong emission at 385 nm and the intensity varied with the interfacial linkage. In electrochemical measurements, both ethynylferrocene- and vinylferrocene-functionalized SiQDs exhibited a pair of well-defined voltammetric peaks at +0.15 V (vs Fc(+)/Fc) in the dark for the redox reaction of the ferrocene/ferrocenium couple; yet under UV photoirradiation, an additional pair of voltammetric peaks appeared at -0.41 V, most likely because of the redox reaction of ferrocene anions formed by photoinduced electron transfer from the SiQD to the ferrocene metal centers.