Molecular Level Understanding of Dynamic Speciation to Inform Complex Reaction Pathways and Control the Rational Synthesis of Ternary Semiconductor Nanoparticles

在化学系大分子、超分子和纳米化学计划的支持下，科罗拉多州立大学的艾米·普利托博士正在开发一种合成工具包，用于了解和控制硒物种的反应性，该工具包可以指导合成相纯的三元半导体纳米颗粒。这些纳米材料由无毒、富含地球的元素组成，具有提供可调节的光电特性的潜力，可用于光伏设备。普利托博士让高中生、本科生和研究生参与了这项研究。Prieto研究团队还在为中学生开发实践学习套件，重点放在太阳能电池上，让他们参与关键的能源主题。这项研究包括阐明在高沸点表面活性剂中单体转化的前体是如何产生相纯的三元半导体纳米颗粒的。这包括通过关注硒单体的刘易斯酸性和碱性来探索导致纯硒磷酸铜纳米颗粒物相的反应组分的形态，了解这些合成参数以可控制地获得缺磷的亚稳态C/P/Se纳米颗粒，以及推断这种化学作用以合成同时包含磷和硒的新的银化合物。这项研究侧重于在原位反应条件下和合成后条件下识别溶液种类和结晶产物的各种工具。通过开发这一用于合成半导体纳米粒子的工具包，具有可调组成、结构和表面化学的纯相三元和四元纳米粒子的反应路径有望被用于未来的光伏发电。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Macromolecular, Supramolecular, and Nanochemistry Program in the Division of Chemistry, Dr. Amy Prieto of Colorado State University is developing a synthetic toolkit for understanding and controlling the reactivity of selenium species that can direct the synthesis of phase pure ternary semiconductor nanoparticles. These nanomaterials, which are composed of non-toxic, earth-abundant elements, have the potential to offer tunable optoelectronic properties that could be exploited in photovoltaic devices. Dr. Prieto involves high school, undergraduate, and graduate students in this research. The Prieto research team is also developing hands-on learning kits for middle school students that focus on solar cells to engage them in key energy topics. This research involves elucidating how the precursor to monomer transformation of Se powder in high boiling point surfactants can yield phase-pure ternary semiconductor nanoparticles. This includes probing the speciation of reactive components that lead to phase pure copper selenophosphate nanoparticles by focusing on the Lewis acidity and basicity of selenium monomers, understanding these synthetic parameters to controllably access phosphorous deficient metastable C/P/Se nanoparticles, and extrapolating this chemistry to synthesize a new silver compound that contains both phosphorus and selenium. This research is focusing on a diverse range of tools to identify solution species and crystalline products under both in-situ reaction conditions and post-synthesis. By developing this tool kit for the synthesis of semiconductor nanoparticles, reaction pathways for pure phase ternary and quaternary nanoparticles with tunable composition, structure, and surface chemistry are expected and these could be exploited in future photovoltaics.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.