MRI: Acquisition of Ultrafast Transient Absorption Spectrometer

该奖项由主要研究仪器(MRI)和化学研究仪器(CRIF)项目支持。埃默里大学的连天全教授和他的同事Brian Dyer、Hayk Harutyunyan、Eilaf Egap和Ajit Sriastava获得了一台能够在飞秒和纳秒尺度上工作的超快瞬时吸收光谱仪。这种仪器可能有助于研究用于可持续能源开发的材料，可持续能源是21世纪科学技术的一项“重大挑战”。为了迎接这一挑战，需要对新的太阳能转换概念、材料和技术进行创新的基础研究。这需要跨越生物、化学、物理和计算科学的高度多学科的研究努力。先进功能材料的成功开发需要了解材料、催化剂(酶)及其界面上的光能、电能和化学能相互转化所涉及的基本过程。探测这些基本过程需要具有足够的时间、光谱和空间分辨率以及可调谐性的先进光谱技术。所要求的光谱仪和相关用户设施提供了这一能力，并极大地加强了埃默里大学和附近机构(包括历史上的黑人学院和大学(HBCU))在亚特兰大和美国东南部的博士后研究员、本科生和研究生的太阳能研究和培训。该仪器用于各种研究，如检测胶体二维硫族镉纳米片中的巨型振子强度跃迁效应，研究与能量研究相关的二维过渡金属二卤化物异质结构中的激子动力学，以及确定纳米晶体/氢酶复合光催化中光驱动的产氢反应机理。该光谱仪还用于研究量子点/共轭聚合物复合体中三重态Dexter的能量转移机制和等离子体激元诱导金属/半导体界面热电子转移的机制。

This award is supported by the Major Research Instrumentation (MRI) and the Chemistry Research Instrumentation (CRIF) Programs. Professor Tianquan Lian from Emory University and colleagues Brian Dyer, Hayk Harutyunyan, Eilaf Egap and Ajit Srivastava have acquired an ultrafast transient absorption spectrometer capable of acting on the femtosecond and nanosecond scales. This instrumentation may aid in studying materials used in the development of sustainable energy which is a "Grand Challenge" for science and technology in the 21st century. To meet this challenge, innovative basic research into new solar energy conversion concepts, materials and technologies is needed. This requires highly multidisciplinary research efforts that span the biological, chemical, physical and computational sciences. The successful development of advanced functional materials requires understanding of fundamental processes involved in the interconversion of light, electrical, and chemical energy in materials, catalysts (enzymes) and at their interfaces. Probing these fundamental processes requires advanced spectroscopic techniques with sufficient time, spectral and spatial resolution and tunability. The requested spectrometers and associated user facility provide this capability and greatly enhance solar energy research and training of postdoctoral fellows and undergraduate and graduate students at Emory and nearby institutions in the metro Atlanta and southeastern USA, including historically black colleges and universities (HBCUs).The spectrometer enhances research and education at all levels. The instrument is used in a variety of investigations such as the examination of the giant oscillator strength transition effects in colloidal, two-dimensional cadmium chalcogenide nanoplatelets of relevance in energy research; studies of exciton dynamics in two-dimensional, transition metal dichalcogenide heterostructures; and the determination of mechanisms of light-driven hydrogen-generating reactions in nanocrystal/hydrogenase hybrid photocatalysis. The spectrometer is also used in investigating the mechanism of triplet Dexter energy transfer in quantum dot/conjugated polymer complexes and in studying the mechanism of plasmon-induced hot electron transfer at a metal/semiconductor interfaces.