Collaborative Research: Development of Colloidal Group IV Doped and Alloyed Nanocrystals and Bulk- heterojunctions

被称为纳米晶体(NC)的超小晶体颗粒的尺寸约为0.00000005英寸，它们的小尺寸导致了在较大的宏观晶体中看不到的有趣和有用的现象。该项目建立在加州大学戴维斯分校(UCD)化学教授苏珊·考兹拉里奇(Susan Kauzlarich)和加州大学圣克鲁斯分校(UCSC)物理学教授苏·卡特(Sue Carter)共同努力的基础上，开发新的NC复合材料，该复合材料使用纳米晶体和金属卤化物钙钛矿的有机金属薄膜，其中钙钛矿是指晶体结构的类型。该团队设计、合成和测量Ge NC的个人和复合性能。Kauzlarich实验室专注于掺杂和合金化Ge的纳米晶体合成和表征，目标是控制尺寸、表面和形状。卡特实验室将这些纳米晶体用于薄膜金属卤化物钙钛矿，重点研究它们的光学和电子传输特性。通过了解组件的界面和电子学，PI将明智地将纳米晶体与薄膜相结合，以获得与其用作光伏相关的光学和传输特性的新功能，并在发电和光电设备技术方面产生更广泛的社会影响。这项研究为下一代科学家提供材料合成、薄膜制造、器件工程和性能测量方面的培训，推动与技术相一致的多学科研究。这项研究将在国家和国际会议上公布，研究结果将发表在同行审查期刊上。此外，UCSC和UCD的教职员工和学生将参与创建量子材料和可打印电子学的课程和动手实验室，这些实验室将通过K-12夏令营和科学课程提供。这个合作项目侧重于开发掺杂和合金化的锗(Ge)纳米晶(NC)的可溶胶体分散体，具有尺寸、表面和形状控制，以及IV族块状异质结(BHJ)的制备和表征，以实现对复合、钝化和电荷传输的控制。它结合了两位PI的专业知识：加州大学戴维斯分校(UCD)化学教授苏珊·考兹拉里奇(Susan Kauzlarich)和加州大学圣克鲁斯分校(UCSC)物理学教授苏·卡特(Sue Carter)。这项研究通过控制NCS的表面和形状以及从溶液中制备IV族体相异质结来扩展IV族的化学，重点是控制组成成分的性质。随着对界面和相对带隙能量的了解，Ge纳米晶的能级通过掺杂和合金化来调节，金属卤化物钙钛矿的能级通过晶格匹配和能带调谐来调节。几种光学、电学和结构方法被用来表征这些胶体材料和它们的薄膜。除了Kauzlarich和Carter实验室现有的表征方法外，在表面光电压谱(SPV)、超快光谱、扫描电子全息显微镜以及扩展X射线吸收精细结构和X射线近边吸收光谱(EXAFS/XANES)方面的合作使进一步表征NCS和BHJ的电子和结构状态成为可能。PI正在明智地将纳米晶体与薄膜相结合，以获得与其用作光伏相关的光学和传输特性的新功能，并在发电和光电设备技术方面产生更广泛的社会影响。这项研究正在为下一代科学家提供材料合成、薄膜制造、器件工程和性能测量方面的培训，推动与技术相一致的多学科研究。这项研究正在国内和国际会议上发表，研究结果发表在同行评议期刊上。此外，UCSC和UCD的教职员工和学生参与创建量子材料和可打印电子学的课程和动手实验室，这些实验室将通过K-12暑期科学夏令营和科学课程提供。

Ultra-small crystalline particles, called nanocrystals (NCs) have dimensions on the order of 0.00000005 inches, and their small size results in interesting and useful phenomena not seen in larger, macroscopic crystals. This project builds on the collaborative efforts between Susan Kauzlarich, a Chemistry professor at the University of California, Davis (UCD) and Sue Carter, a Physics professor at the University of California, Santa Cruz (UCSC) to develop new NC composites that employ nanocrystals and a organometallic film of a metal halide perovskite, where perovskite refers to the type of crystalline structure. The team designs, synthesizes and measures germanium NC individual and composite properties. The Kauzlarich lab is focused on nanocrystal synthesis and characterization of doped and alloyed germanium with the goal of controlling size, surface and shape. The Carter lab employs these nanocrystals in thin film metal halide perovskites with a focus on their optical and electron transport properties. By understanding the interfaces and electronics of the components, the PIs will judiciously combine nanocrystals with films to gain new functionality in their optical and transport properties relevant to their use as photovoltaics, with broader societal impact in electrical generation and photoelectronic device technologies. This research provides training for next generation scientists on materials synthesis, thin film fabrication, device engineering, and property measurements, advancing multidisciplinary research aligned with technology. The research will be presented at national and international meetings and the findings published in peer-review journals. In addition, UCSC and UCD faculty and students will be involved in creating curriculum and hands-on laboratories in quantum materials and printable electronics that will be offered through K-12 summer science camps and science classes.This collaborative project is focused on the development of soluble colloidal dispersions of doped and alloyed germanium (Ge) nanocrystals (NCs) with size, surface, and shape control and the fabrication and characterization of group IV bulk-heterojunctions (BHJs) to achieve control of the recombination, passivation, and charge transport. It combines the expertise of two PIs: Susan Kauzlarich, a Chemistry professor at the University of California, Davis (UCD) and Sue Carter, a Physics professor at the University of California, Santa Cruz (UCSC). This study expands the chemistry of group IV with control of surface and shape of the NCs and with fabrication of group IV bulk-heterojunctions from solutions, with a focus on control over the properties of the constituent components. As an understanding of the interfaces and relative bandgap energies is achieved, the energy levels of the Ge nanocrystals are being tuned through doping and alloying and the metal halide perovskite through lattice matching and band tuning. Several optical, electrical, and structural methods are being used to characterize these colloidal materials and their thin films. In addition to characterization methods existing in the Kauzlarich and Carter labs, collaborations on surface photovoltage (SPV) spectroscopy, ultrafast spectroscopy, Scanning Transmission Electron Holographic Microscopy, and Extended X-ray Absorption Fine Structure and X-ray Absorption Near Edge Spectroscopy (EXAFS/XANES) are enabling further characterization of the electronic and structure states of the NCs and BHJs. The PIs are judiciously combining nanocrystals with films to gain new functionality in their optical and transport properties relevant to their use as photovoltaics, with broader societal impact in electrical generation and photoelectronic device technologies. This research is providing training for next generation scientists on materials synthesis, thin film fabrication, device engineering, and property measurements, advancing multidisciplinary research aligned with technology. The research is being presented at national and international meetings and the findings published in peer-review journals. In addition, UCSC and UCD faculty and students are involved in creating curriculum and hands-on laboratories in quantum materials and printable electronics that are being offered through K-12 summer science camps and science classes.