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，尺寸在0.000001毫米左右(相当于5-10个原子)，具有有趣的性质，可以导致新的化学。金属氧化物纳米晶是本研究的主题，是很有前途的下一代材料，可用作催化剂、储能材料、电子器件元件、传感器和诊断探针。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性能。哈奇森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、连续地添加金属和氧原子，以高度受控的方式生长纳米晶体。这种连续的生长过程被称为“活生长”，它以高精度将原子附着在纳米晶体上，允许同时控制尺寸、均匀性和成分。所有这些性质对于特定的潜在应用都很重要。研究人员正在开发生产新的纳米材料的一般方法，这些材料将用于工业，如薄膜、磁性材料和催化剂。哈奇森博士的研究吸引了一个由本科生和研究生组成的多元化、跨学科的群体，其中包括代表不足的少数族裔。除了科学培训外，学生还制定和实施书面的专业发展计划，并接受创新和创业方面的培训，以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。这些学生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。在这项研究计划中，俄勒冈大学的Hutchison博士在大分子、超分子和纳米化学(MSN)计划的支持下，研究无机纳米晶体的“活生长”合成，目的是获得对核直径和均匀、核成分、掺杂水平和核壳结构的同时控制。活性生长合成的工作原理与活性聚合产生的聚合物具有可控的相对分子质量、共聚物组成和嵌段共聚物结构大体相同。Hutchison博士生产的混合金属氧化物纳米晶很难通过热分解或其他高温方法合成。这项研究已经建立了一种生产原子级成分和大小可控的新金属氧化物的一般方法。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博士积极地让不同的本科生和研究生团队参与他的研究，并通过有针对性的专业发展活动来加强他们的研究培训，例如创新和创业培训。研究成果通过科学出版物、区域会议、研究生课程和行业研讨会进行传播。

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.