Silicon Nanochemistry

硅纳米化学

• 批准号: RGPIN-2014-04600
• 负责人: Ozin, Geoffrey
• 金额: $ 7.29万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=661371
• 关键词: Silicon; Nanochemistry

The focus of the research centers on new classes of silicon nanocrystals. The inspiration stems from our newfound ability to separate ensembles of poly-dispersed silicon nanocrystals into mono-dispersed fractions in the range of 1-5 nm, which has enabled the first recorded measurement and evaluation of the size-dependent chemical, physical and biological properties of silicon nanocrystals. Our proposed future research will expand and enrich upon these significant advances through four main themes. The first focuses on the synthesis of a novel class of silicon nanocrystals with redox active functional groups chemically tethered to the nanocrystal surface. This will enable the surface charge and hence electrical and optical properties of the silicon nanocrystals to be fine-tuned by chemical and/or electrochemical means. The archetype ncSi:R will be comprised of a redox active functional group R covalently attached to the surface of a hydride-terminated nanocrystalline silicon precursor ncSi:H via hydrosilation with an alkene or alkyne. Through chemical or electrochemical control of the number and extent of oxidation (p,q) of the capping R groups on the surface of the ncSi core the capped silicon nanocrystals can be transformed to ncSi:(1-p)R.pRq, where R will be chosen from metallocenes Cp2M, M = V, Cr, Mn, Fe, Co, Ni, coordination compounds RuBipy, aromatics Ar and fullerenes C60. The primary goal of this project is to demonstrate redox tuning of the electrical and optical properties of silicon nanocrystals. The second focuses on the synthesis of `naked' silicon nanocrystals, devoid of surface organics, with controlled surface charge and colloid-stability, which will provide unparalleled access to the chemical and physical properties of the silicon core unimpeded by surface organics. In this project the archetypes [ncSi+]]X-] will be synthesized from the hydride or chloride capped precursors ncSi:H or ncSi:Cl using reagents, such as HBF4.Et2O, BH3.THF and AgPF6 to form charge-stabilized [ncSi+][BF4-], [ncSi+][BH4-] and [ncSi+][PF6-], respectively. The third focuses on the synthesis and characterization of doped forms of nanosilicon using radio-frequency plasma excitation of SiH4-PH3 and SiH4-B2H6 gaseous mixtures as well as HF/H2O/FeCl3 etching of n- and p-doped Si wafers, the goal of the project being determination of the dopant concentration and spatial location of B and P dopants in the ncSi, measurement of charge transport, optical and optoelectronic properties of n- and p-doped ncSi films as well as films with ncSi p-n junctions, potentially enabling new generation ncSi devices. The fourth is founded upon the envisioned utility of colloidally-stable nanocrystal `silicon inks' for the fabrication of printable multicolor optoelectronic devices. The objective is to learn how to tailor the sizes and surfaces of silicon nanocrystals to control their solubility in polar and non-polar solvents, enhance their electrical charge transport properties, fine-tune their wavelength, and maximize their photoluminescence and electroluminescence efficiency across the visible spectral range, to optimize the stability and performance of multicolor silicon light emitting diodes, SiLEDs.

研究的重点集中在新的硅纳米晶体上。灵感来自于我们的新发现的能力，可以将多分散的硅纳米晶体分离为1-5 nm范围内的单分散分数，这使得能够对硅Nanocrystals的尺寸依赖性化学，物理和生物学特性进行第一个记录的测量和评估。我们提出的未来研究将通过四个主要主题来扩展和丰富这些重大进展。第一个侧重于与氧化还原活性官能团化学束缚在纳米晶体表面的新型硅纳米晶体的合成。这将使硅纳米晶体的表面电荷以及通过化学和/或电化学方法对硅纳米晶体的电气和光学特性进行微调。原型NCSI：R将由一个氧化还原活性官能团R组成，该官方官能组与氢化物终止的纳米晶体硅硅硅前体NCSI：H通过用烷烃或烯基的氢溶解。 Through chemical or electrochemical control of the number and extent of oxidation (p,q) of the capping R groups on the surface of the ncSi core the capped silicon nanocrystals can be transformed to ncSi:(1-p)R.pRq, where R will be chosen from metallocenes Cp2M, M = V, Cr, Mn, Fe, Co, Ni, coordination compounds RuBipy, aromatics Ar and Fullerenes C60。该项目的主要目标是证明硅纳米晶体的电和光学特性的氧化还原调整。第二个侧重于没有表面电荷和胶体稳定性的“裸硅纳米晶体，没有表面有机物，这将提供无与伦比的硅芯的化学和物理特性，未经表面有机物的影响。在此项目中，将使用氢化物​​或氯化物盖的前体NCSI：H或NCSI：CL使用试剂（例如HBF4.ET2O，BH3.THF和AGPF6）形成电荷稳定的[NCSI+]+] [bf4-]，[ncsi+] [bf4-]，[ncsi+]，[ncsi+]，[ncsi+]]] x-] x-] x-] [NCSI+] [PF6-]。第三个侧重于使用SIH4-PH3和SIH4-B2H6气体混合物以及HF/H2O/FECL3蚀刻n-和P-poped Si Wafer的射击量和dopiant of Provestions的射击，并确定了dopant of dopant of的hf/h2o/fecl3蚀刻量和dopian dopant of dopant of dopant of and d dopiant of dopant of and d dopiant of s in and dopians of dopant of sih4-ph3和sih4-b2H6气体混合物的合成和表征纳米硅的掺杂和表征。 NCSI，N-doped NCSI膜的电荷传输，光学和光电特性以及具有NCSI P-N连接的膜，有可能启用新一代NCSI设备。第四个建立在胶体稳定的纳米晶体“硅油墨”的设想实用性上，用于制造可打印的多色光电设备。 The objective is to learn how to tailor the sizes and surfaces of silicon nanocrystals to control their solubility in polar and non-polar solvents, enhance their electrical charge transport properties, fine-tune their wavelength, and maximize their photoluminescence and electroluminescence efficiency across the visible spectral range, to optimize the stability and performance of multicolor silicon light emitting diodes, SiLEDs.