Research Initiation Award: Photoinduced Redox Reactions on Semiconductor Particles; Photoelectrochemistry for Organic Synthesis

李玉卓9308282本工作的目标是利用多相半导体体系进行光催化有机合成。重点放在制药、农用化学品、聚合物和染料工业中有用的中间体。设计了能效和成本效益高的反应堆配置，并测试了新的半导体系统。具体任务包括：应用光催化还原(使用二氧化钛光催化剂)醛、叠氮化合物、亚硝酸盐和硝基化合物；在半导体表面将二氧化碳光催化固定为芳香族化合物；制备以氧化铁包裹的三氧化钨为核心的单分散粒子，并评估其在氧化还原反应中的光催化潜力；制备包覆导电聚合物的单分散二氧化钛，并评价其在还原硝基化合物中的效用；以及设计一种流动式光化学反应装置，用于高产品产量和低溶剂消耗。在这项研究中，探索了以微粒半导体为催化剂的有机化合物的光诱导(光引发)转化。重点是还原含氧或含氮的有机化合物。这种方法不需要消耗性还原剂，而消耗性还原剂是有毒金属废物的主要来源。这种方法除了有可能避免有毒副产品外，还可用于销毁现有的有毒废物。

Yuzhuo Li 9308282 The objective of this work is to use heterogenous semiconductor systems for photocatalytic organic synthesis. Emphasis is on intermediates useful in the pharmaceutical, agrochemical, polymer, and dye industries. Reactor configurations that are energy efficient and cost effective are designed and new semiconductor systems are tested. Specific tasks include applications of photocatalytic reduction (using titania photocatalyst) to aldehydes, azides, nitrites, and nitro compounds; photocatalytic fixation of carbon dioxide into aromatic compounds on semiconductor surfaces; preparation of monodispersed particles with a core of tungsten trioxide coated with ferric oxide and evaluation of their photocatalytic potential in redox reactions; preparation of monodispersed titania coated with conducting polymers and evaluation of their utility in the reduction of nitro compounds; and design of a flow photochemical reactor for high product output and low solvent consumption. In this study, photoinduced (light inititiated) transformations of organic compounds using particulate semiconductors as catalysts are explored. Emphasis is on reduction of organic compounds containing oxygen or nitrogen. This approach requires no expendable reducing agents, which are a major source of toxic-metal waste. In addition to its potential for avoidance of toxic byproducts, this approach may also be useful for destruction of existing toxic wastes.