Understanding Thermal Energy Scavenging in All-Inorganic Perovskite Nanocrystals

了解全无机钙钛矿纳米晶体的热能清除

• 批准号: 2131408
• 负责人: Simon North
• 金额: $ 46.5万
• 依托单位: Texas A&M University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-11-01 至 2024-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2131408&HistoricalAwards=false
• 关键词: Understanding; Thermal; Energy; Scavenging; Inorganic

NON-TECHNICAL SUMMARY:The industrial revolution was enabled by heat engines that perform work by converting thermal energy (heat or high temperature) to mechanical energy. Recently, several advantages have been theorized for heat engines that do work by converting heat into light, similar to how traditional engines use fluids or gases such as steam. However, there are very few known optical materials that can efficiently convert heat to optical energy, in part because heat degrades their optical performance. This project will prepare new classes of materials with precise structural and chemical properties on the nanoscale to allow for efficient conversion between thermal and light energy. The research team will examine how increasing the thermal energy in these materials can also result, unusually, in an increase of the energy of light that they emit. This phenomenon can ultimately lead to significantly more efficient heat engines with no moving parts, better solar cells, or new methods of refrigeration that do not require compressed gasses or mechanical components. The project will support graduate and undergraduate research students working in the PI’s laboratory as well as the development of novel curricula and technological tools for teaching large-format freshman chemistry courses. The primary investigator will refine some of the best innovations developed during the pandemic and take advantage of these for the transition back to classroom instruction.TECHNICAL SUMMARY:This project will study thermal energy scavenging by one-photon optical upconversion, also known as anti-Stokes photoluminescence. Upconversion results when heated photoluminescent materials emit band-edge photons during subgap excitation, while simultaneously decreasing in temperature. Inorganic lead halide perovskite nanocrystals are a champion materials system for efficient one-photon upconversion, but fundamental details of the mechanism are unknown, impeding rational strategies for further development. Spectroscopic studies conducted by the PI’s team will elucidate a clear mechanism for optical up-conversion, as well as outline the structure-property relationships that define the absorption cross section, bandwidth, temperature response, and the fundamental limits on efficiency. The research team will vary composition and morphology during nanocrystal synthesis. Structural parameters such as crystal phase, shape, and surface-to-volume ratio will be tracked using high resolution transmission electron microscopy, and powder X-ray diffractometry. In parallel, the team will perform photoluminescence excitation spectroscopy and photoluminescence lifetime studies. These experiments will quantify the dependence on above-gap or below-gap excitation wavelength, power density, and nanocrystal temperature to identify the unique states that mediate the interconversion of vibrational and electronic excitations, while preserving the intrinsic, near-ideal luminescence efficiency of the nanocrystals. The overarching goal is to understand the thermal energy scavenging properties of inorganic lead halide perovskite nanocrystals to create luminescent materials that can aid thermal-to-optical energy conversion, optical up-conversion, and optically driven refrigeration.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.

非技术摘要：工业革命是通过将热能（热量或高温）转换为机械能来进行工作的热机实现的，最近，通过将热能转换为光来进行工作的热机的一些优点已经被理论化。然而，很少有已知的光学材料能够有效地将热量转化为光能，部分原因是热量会降低其光学性能，该项目将制备具有精确结构的新型材料。和化学性质研究小组将研究如何增加这些材料中的热能，从而最终导致它们发出的光能增加。更高效的无移动部件的热机、更好的太阳能电池或不需要压缩气体或机械部件的新制冷方法该项目将支持在 PI 实验室工作的研究生和本科生研究人员以及新颖的开发。课程和技术主要研究者将完善大流行期间教学中开发的一些最佳创新，并利用这些工具过渡到课堂教学。技术摘要：该项目将研究热能清除方法光子光学上转换，也称为反斯托克斯光致发光，是当加热的光致发光材料在亚间隙激发期间发射带边光子，同时降低温度时产生的。钙钛矿纳米晶体是单光子上转换的冠军材料系统，但该机制的基本细节尚不清楚，这阻碍了PI团队进行的进一步开发的合理策略，也将阐明一种清晰有效的光学上转换机制。概述了定义吸收截面、带宽、温度响应和效率基本限制的结构-性能关系。研究小组将在纳米晶体合成过程中改变成分和形态。晶相、形状和表面积与体积比等结构参数将使用高分辨率透射电子显微镜和粉末 X 射线衍射法进行跟踪，同时，该团队将进行光致发光激发光谱和光致发光寿命研究。将量化对带隙上方或带隙下方激发波长、功率密度和纳米晶体温度的依赖性，以确定介导振动和电子相互转换的独特状态总体目标是了解无机卤化铅钙钛矿纳米晶体的热能清除特性，以创造有助于热能到光能转换的发光材料。 -转换和光学驱动制冷。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查进行评估，被认为值得支持标准。

项目成果

Kinetic Control for Continuously Tunable Lattice Parameters, Size, and Composition during CsPbX 3 (X = Cl, Br, I) Nanorod Synthesis

CsPbX 3 (X = Cl, Br, I) 纳米棒合成过程中连续可调晶格参数、尺寸和成分的动力学控制

• DOI: 10.1021/acsnano.2c02474
• 发表时间: 2022-05
• 期刊: ACS Nano
• 影响因子: 17.1
• 作者: Wen, Je;Rodríguez Ortiz, Freddy Alberto;Champ, Anna;Sheldon, Matthew T.
• 通讯作者: Sheldon, Matthew T.

The Anisotropic Complex Dielectric Function of CsPbBr 3 Perovskite Nanorods Obtained via an Iterative Matrix Inversion Method

迭代矩阵反演法获得CsPbBr 3 钙钛矿纳米棒的各向异性复介电函数

• DOI: 10.1021/acs.jpcc.3c03423
• 发表时间: 2023-07
• 期刊: The Journal of Physical Chemistry C
• 作者: Rodríguez Ortiz, Freddy A.;Zhao, Boqin;Wen, Je;Yim, Ju Eun;Bauer, Giselle;Champ, Anna;Sheldon, Matthew T.
• 通讯作者: Sheldon, Matthew T.

Promoting solution-phase superlattices of CsPbBr 3 nanocrystals

促进 CsPbBr 3 纳米晶的溶液相超晶格

• DOI: 10.1039/d3nr00693j
• 发表时间: 2023-06
• 期刊: Nanoscale
• 影响因子: 6.7
• 作者: Mireles Villegas, Noel;Hernandez, Josue C.;John, Joshua C.;Sheldon, Matthew
• 通讯作者: Sheldon, Matthew

Quantifying Order during Field-Driven Alignment of Colloidal Semiconductor Nanorods

胶体半导体纳米棒场驱动排列期间的量化顺序

• DOI: 10.1021/acsnano.1c08488
• 发表时间: 2022-03
• 期刊: ACS Nano
• 影响因子: 17.1
• 作者: Ratnaweera, Rivi J.;Rodríguez Ortiz, Freddy A.;Gripp, Nicholas J.;Sheldon, Matthew T.
• 通讯作者: Sheldon, Matthew T.