Living Growth Synthesis of Metal Oxide Nanocrystals: Toward Enhanced Control of Composition, Size and Uniformity

纳米晶体是非常小的晶体，尺寸约为0.000001毫米（相当于5-10个原子的大小），具有有趣的特性，可以导致新的化学。金属氧化物纳米晶体是本研究的主题，是有希望用作催化剂、储能材料、电子器件组件、传感器和诊断探针的下一代材料。化学家需要更好的方法在原子水平上控制纳米晶体的组成和结构，以便能够利用这些新材料的特性。Hutchison博士正在开发一种新的合成方法，通过在纳米晶体表面连续、有序地添加金属和氧原子，以高度可控的方式生长纳米晶体。这种连续生长过程被称为“活生长”，它以高精度将原子附着在纳米晶体上，从而可以同时控制尺寸、均匀性和成分。所有这些特性对于特定的潜在应用都很重要。研究人员正在开发生产新型纳米材料的通用方法，这些纳米材料将用于工业中的薄膜、磁性材料和催化剂。哈奇森博士的研究吸引了一个多元化的跨学科本科生和研究生群体，其中包括代表性不足的少数族裔。除了他们的科学训练，学生制定和实施书面的专业发展计划，并接受创新和创业培训，使他们能够提高他们的研究的社会影响。研究结果通过区域会议与公众分享。学生们在俄勒冈大学先进材料表征中心提供的纳米材料研讨会上与工业界的科学家互动。在这个研究项目中，俄勒冈大学的Hutchison博士得到了大分子、超分子和纳米化学（MSN）项目的支持，研究无机纳米晶体的“活生长”合成，目的是同时控制核心直径和均匀性、核心组成、掺杂水平和核心-壳结构。活性生长合成的工作原理与活性聚合产生分子量、共聚物组成和嵌段共聚物结构可控的聚合物的方式大致相同。哈奇森博士生产的混合金属氧化物纳米晶体很难通过热分解或其他高温方法合成。这项研究建立了一种生产具有可控原子级成分和尺寸的新型金属氧化物的通用方法。该项目建立了对产生这些纳米晶体的反应的基本理解，并支持在薄膜、磁性和催化研究中的新应用。Hutchison博士在他的研究中积极参与本科生和研究生的多元化团队，并通过有针对性的专业发展活动（如创新和创业培训）增强他们的研究培训。研究结果通过科学出版物、区域会议、研究生课程和工业讲习班传播。

Nanocrystals, very small crystals with sizes on the order of 0.000001 millimeters (equal in size to 5-10 atoms), have interesting properties that can lead to novel chemistry. Metal oxide nanocrystals, the subject of this study, are promising next-generation materials for use as catalysts, energy storage materials, electronic device components, sensors, and diagnostic probes. Chemists need better ways to control the composition and structure of the nanocrystals at the atomic level in order to be able to harness the properties of these new materials. Dr. Hutchison is developing a new synthesis approach that grows nanocrystals in a highly controlled manner by the continuous, sequential addition of metal and oxygen atoms to the surface of a nanocrystal. Such a continuous growth process, referred to as "living growth", attaches atoms to the nanocrystals with high precision, permitting simultaneous control of size, uniformity, and composition. All of these properties are important for specific potential applications. The researchers are developing general approaches to the production of new nanomaterials to be used in industry as thin film, magnetic materials, and catalysts. Dr. Hutchison's research attracts a diverse, interdisciplinary group of undergraduate and graduate students, including underrepresented minorities. In addition to their scientific training, students develop and implement written professional development plans and receive training on innovation and entrepreneurship so that they can enhance the societal impact of their research. The results of the research are shared with the general public through the regional meetings. The students interact with scientists from industry at nanomaterial workshops offered at the University of Oregon's Center for Advanced Materials Characterization. In this research program, Dr. Hutchison of the University of Oregon is supported by the Macromolecular, Supramolecular and Nanochemistry (MSN) Program to investigate "living growth" syntheses of inorganic nanocrystals with the aim of gaining simultaneous control of core diameter and uniformity, core composition, doping levels and core-shell structures. Living growth synthesis works in much the same way that living polymerization yields polymers with controlled molecular weight, copolymer composition and block copolymer structures. Dr. Hutchison produces mixed metal oxide nanocrystals that have been difficult to synthesize by thermal decomposition or other high temperature methods. The research has established a general approach to producing new metal oxides with controlled atomic-level composition and size. The project builds fundamental understanding of the reactions producing these nanocrystals and supports new applications in thin film, magnetic and catalysis research. Dr. Hutchison actively engages a diverse team of undergraduate and graduate students in his research and augments their research training with targeted professional development activities such as training on innovation and entrepreneurship. The results of the research are disseminated through scientific publication, the regional meetings, graduate courses, and industry workshops.