Nanostructured molecular clusters and solids from heavier group 15 cyanate analogues: A novel route to metal pnictides

金属磷属元素化物（含有氮、磷、砷、锑和/或铋的化合物）是采用丰富的结构和化学计量的各种固体家族。在它们的许多应用中，它们被用作熏蒸剂、杀虫剂、照明弹，也许最值得注意的是，作为半导体。它们的物理和化学性质的多样性使得这些化合物在一系列技术应用中引起兴趣。然而，虽然许多这样的物种可以很容易地使用各种方法合成，但这些通常需要很高的能量成本。此外，现有的技术方法仍然严重限制了获得明确定义的纳米级材料或介观结构固体的能力。这是我提议应对的挑战。我们的目标是研究使用替代pnictogen含试剂合成新的集群，纳米粒子和结构化固体。该提案的重点是较重的pnictogene含有类似物的氰酸根阴离子，PnCO-（Pn = P-Bi）与过渡和后过渡金属盐的反应性，因为使用这些化合物的固体和分子簇的合成在很大程度上是未经开发的。第一个目标是扩展氰酸盐的重族15类似物的化学，以合成SbCO-和BiCO-为目标。然后，溶液相之间的复分解反应较重的第15族氰酸酯类似物（PnCO-）与各种过渡和后过渡金属盐将进行，目的是开发一种新的自下而上的方法，以金属pnictides。在本文中，主要焦点是建立对固体形成的控制，特别关注生成定义明确的纳米颗粒和结构化固体，因为尺寸减小的半导体结构如纳米颗粒和量子点正在影响各种科学和技术领域（例如生物测定或光电器件）。最后，氰酸酯类似物应该是合成魔法大小的分子簇和量子点（QD）的合适前体。这种簇的热处理也可以用于III/V族QD的单分散样品的成核，III/V族QD是迄今为止证明在合成上非常具有挑战性的化合物家族。

Metal pnictides (compounds containing nitrogen, phosphorus, arsenic, antimony and/or bismuth) are a varied family of solids that adopt a wealth of structures and stoichiometries. Amongst their many applications they have been employed as fumigants, pesticides, flares and, perhaps most notably, as semiconductors. The diversity of their physical and chemical properties makes such compounds interesting for a range of technological applications. However, while many such species can be readily synthesized using a variety of methods, these often come at a high energetic cost. Moreover, the ability to access well defined nanoscale materials or mesostructured solids is still significantly limited by existing technological methods. This is the challenge I propose to address. The goal is to study the use of alternative pnictogen-containing reagents for the synthesis of novel clusters, nanoparticles and structured solids. The proposal focuses on the reactivity of heavier pnictogen-containing analogues of the cyanate anion, PnCO– (Pn = P–Bi) with transition- and post-transition metal salts, as the use of these compounds for the synthesis of solids and molecular clusters is largely unexplored. The first objective is to extend the chemistry of the heavier group 15 analogues of cyanate to target the synthesis of SbCO– and BiCO–. Then, solution-phase metathesis reactions between heavier group 15 cyanate analogues (PnCO–) with a variety of transition- and post-transition metal salts will be conducted, with the aim of developing a novel bottom-up approach to metal pnictides. Herein, the main focus is establishing control over solid formation, with a particular focus on generating well-defined nanoparticles and structured solids as dimensionally reduced semiconductor structures such as nanoparticles and quantum dots are impacting a diverse set of scientific and technological fields (e.g. bioassaying or optoelectronic devices). Finally, the cyanate analogues should be suitable precursors for the synthesis of magic-sized molecular clusters and quantum dots (QDs). The thermal treatment of such clusters may also be used for the nucleation of monodisperse samples of group III/V QDs, a family of compounds that have thus far proven very challenging synthetically.