Novel synthetic routes towards zinc nitride quantum dots and half-heusler compounds such as LiZnN

该项目的目的是利用空气敏感的无机和有机金属化学，为一系列基于氮化物的发光量子点材料开发新的化学路线。从生物成像到太阳能和显示器，量子点已经成为一种关键材料。对于这种应用，下一代器件需要无重金属、稳定和明亮的发光材料。目前，本项目主要研究氮化锌(ZN_3N_2)量子点。由于它们从近红外(780 nm-2500 nm)到光谱部分(400 nm-750 nm)的可见光发射可调，因此具有极大的科学意义。氮化锌量子点在开发太阳能电池、电子学和生物医学应用方面具有潜在的应用价值。氮化锌还有一个额外的优势，它不像目前胶态的、发育良好的纳米晶体(如：硫化镉、硫化铅或磷化铟)，它由无毒和富含稀土的材料组成。目前合成氮化锌的方法受到严重的限制，据报道，合成氮化锌的方法是由牛津大学的一个研究小组在高温(225℃)下使用高度易燃的二乙基锌和爆炸性氨气合成的。我们的目标是使用一种更方便、更安全的有机金属方法，使用碘化锌和锂胺前驱体来生产明亮的红色发光材料。温度、配体筛选试验和反应容器条件的改变将被修改。使用发射光谱、吸收光谱、X射线衍射、XPS、透射电子显微镜、SAED、EDX和QY测量来确定样品及其元素成分的一致性。将尝试使用硫化锌外壳和/或InN梯度合金材料对这些材料进行壳化。

The aim of the project is to develop new chemical routes for a range of luminescent nitride-based quantum dot materials, using air-sensitive inorganic and organometallic chemistry. Quantum dots have emerged as a key material in numerous applications, from biological imaging, to solar energy and displays. For such applications, heavy metal free, stable and brightly emitting materials are necessary for the next generation of devices. Currently this project focuses on zinc nitride (Zn3N2) quantum dots (QDs). These are of great scientific interest due to their tune-able emission, from near infra-red (780 nm - 2500 nm) into the visible of the spectrum part (400 nm - 750 nm). Zinc nitride QDs have potential to be useful in the development of solar cells, electronics and in biomedical applications. Zinc nitride has the added advantage that, unlike current colloidal, well-developed nanocrystals (i.e. CdSe, PbS or InP), it consists of non-toxic and earth abundant materials. The current methods to synthesise zinc nitride are severely limited and have been reported to have been synthesised using highly pyrophoric diethyl zinc and explosive ammonia gas at high temperatures (225oC) from a research group in Oxford. We aim to produce bright red emitting materials using a more convenient and safer organometallic method, using zinc iodide and lithium amide precursors. Temperatures, ligand screening tests and change in reaction vessel conditions will be modified. Using emission spectra, absorption spectra, X-ray diffraction, XPS, TEM, SAED, EDX and QY measurements to determine the identity of the sample and its elemental constituents. An attempt will be made to shell these materials will be made using ZnS shells and/or InN graded alloy materials.