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Transition Metal Pnictide Nanoparticles for Energy-Relevant Applications

用于能源相关应用的过渡金属磷化物纳米颗粒

基本信息

批准号：
1904775
负责人：
Stephanie Brock
金额：
$ 46.82万
依托单位：
Wayne State University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-06-15 至 2025-08-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1904775&HistoricalAwards=false
关键词：
Transition Metal Pnictide Nanoparticles Energy

项目摘要

NON-TECHNICAL SUMMARYThrough this research project, which is supported by the Solid State and Materials Chemistry program at NSF, new materials for magnetic refrigeration (MR) that exploit earth-abundant transition metal phosphide, arsenide or antimonide nanoparticles are established. Traditional refrigeration and air-conditioning are based on the compression and expansion of an inert gas in a process that consumes a whopping 17% of the electrical energy consumed globally. In addition to being energy intensive, inevitable refrigerant leaks of the hydrochlorofluorocarbon gases (HCFs) are projected to contribute 13% of the global greenhouse gas emissions by 2030. Magnetic refrigeration is a process that relies on magnetic polarization within a solid material (not a gas) to absorb and release heat. While MR is theoretically capable of 50% more energy-efficient refrigeration than standard vapor-compression approaches, it is not widely adopted yet. This is due in part to an absence of materials that are simultaneously (1) high-performing in the temperature region of interest, (2) can be efficiently cycled with minimal energy losses, (3) are inexpensive, and (4) are based upon materials with high natural abundance. Some earth-abundant materials known to be active for MR but are not routinely used because of inefficiencies from cycling losses. As part of this project these materials are prepared as nanoparticles. Prof. Brock and her group at Wayne State University expect the decrease in the size of the particles to reduce barriers for magnetic polarization, thereby enabling efficient cycling. To evaluate this hypothesis, the researchers carry out tests on a series of structurally-related materials with different compositions as part of this project. In addition to providing key insights to the development of viable MR technologies, the project also includes training and mentoring of students in interdisciplinary collaborative research and introduction of Detroit-area 6th-9th grade students, many of which are minorities, to materials chemistry through hands-on activities for outreach events.TECHNICAL SUMMARYWith support from the Solid State and Materials Chemistry program at NSF this project establishes the fundamental characteristics of transition metal pnictide (pnicogen = Group 15 element) nanomaterials relevant to alternative energy applications, specifically focusing on magnetic refrigeration (MR). Many transition metal pnictide materials are well-suited to MR applications, displaying a large magnetocaloric effect (MCE, a large change in magnetic entropy during polarization and depolarization) near room temperature. The largest effects are associated with first-order (abrupt) phase transitions from the ferromagnetic to the paramagnetic state at TC, but these are also quite sharp (do not span the temperature range of interest). Nanostructuring has been suggested as a means to broaden the temperature range over which MCE is maximized; blending particles with differing TC's to extend the temperature range over which appreciable magnetic entropy can be attained. In this project, "materials opportunities" in the search for functional magnetocalorics among nanoscale transition metal pnictides, are pursued via three aims. In Aim 1, magnetic entropy data is collected on P-doped MnAs nanoparticle samples and correlated to single particle magnetic force microscopy data to discern how polydispersity affects the ensemble behavior of the samples, in terms of producing uniform magnetic entropy responses over large temperature ranges. In Aim 2, a relative reactivity scale for metal precursors with P (trioctylphosphine), is created as a way to design new, more complex MCE materials (ternary and quaternary phosphide phases). Finally, in Aim 3 intrinsic challenges that face the exploitation of nanomaterials for magnetic refrigeration are addressed, including reduction of the magnetic entropy due to surface oxidation. Insights from the reduction strategy are leveraged to target new antimonide phase for MR. In addition to providing key insights to the development of viable MR technologies, the project also includes training and mentoring of students in interdisciplinary collaborative research and introduction of Detroit-area 6th-9th grade students, many of which are minorities, to materials chemistry through a hands-on activity based on liquid crystal sensors for the annual Wayne State University STEM day event.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.

本研究项目由美国国家科学基金会固态与材料化学项目资助，利用地球上丰富的过渡金属磷化物、砷化物或锑化物纳米颗粒，建立了用于磁制冷（MR）的新材料。传统的制冷和空调是基于惰性气体的压缩和膨胀，这一过程消耗了全球17%的电能。除能源密集型外，预计到2030年，不可避免的制冷剂氟氯烃气体泄漏将占全球温室气体排放量的13%。磁制冷是一种依靠固体材料（不是气体）内部的磁极化来吸收和释放热量的过程。虽然MR在理论上比标准的蒸汽压缩方法节能50%，但它还没有被广泛采用。这部分是由于缺乏同时(1)在感兴趣的温度区域具有高性能的材料，(2)可以以最小的能量损失有效地循环，(3)价格低廉，(4)基于具有高天然丰度的材料。一些地球上储量丰富的材料已知对MR有活性，但由于循环损耗而效率低下，因此没有常规使用。作为这个项目的一部分，这些材料被制备成纳米颗粒。布洛克教授和她在韦恩州立大学的研究小组预计，颗粒尺寸的减小可以减少磁极化的障碍，从而实现有效的循环。为了评估这一假设，作为该项目的一部分，研究人员对一系列具有不同成分的结构相关材料进行了测试。除了为可行的磁共振技术的发展提供关键见解外，该项目还包括对学生进行跨学科合作研究的培训和指导，并通过实践活动向底特律地区的6 -9年级学生（其中许多是少数民族）介绍材料化学。在美国国家科学基金会固态和材料化学项目的支持下，该项目建立了与替代能源应用相关的过渡金属pnictide （pnicogen =第15族元素）纳米材料的基本特性，特别是专注于磁制冷（MR）。许多过渡金属微粒材料非常适合于磁共振应用，在室温附近显示出很大的磁热效应（MCE，在极化和退极化期间磁熵的大变化）。最大的影响与从铁磁到顺磁状态的一阶（突然）相变有关，但这些也相当尖锐（不跨越感兴趣的温度范围）。纳米结构被认为是扩大MCE最大化温度范围的一种手段；混合具有不同TC的粒子，以扩大可以获得可观磁熵的温度范围。在这个项目中，在纳米级过渡金属化合物中寻找功能磁热学的“材料机会”有三个目标。在Aim 1中，收集了p掺杂MnAs纳米颗粒样品的磁熵数据，并将其与单颗粒磁力显微镜数据相关联，以辨别多分散性如何影响样品的系综行为，在大温度范围内产生均匀的磁熵响应。在Aim 2中，创建了具有P（三辛基膦）的金属前体的相对反应性尺度，作为设计新的，更复杂的MCE材料（三元和四相磷化物）的一种方法。最后，在Aim 3中，解决了用于磁制冷的纳米材料开发所面临的内在挑战，包括由于表面氧化而导致的磁熵降低。除了为可行的MR技术的发展提供关键见解外，该项目还包括在跨学科合作研究中培训和指导学生，并引入底特律地区6 -9年级的学生，其中许多是少数民族。在一年一度的韦恩州立大学STEM日活动中，通过基于液晶传感器的动手活动来了解材料化学。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Magnetic Fe 1.3 Ni 0.7 P Aerogels Prepared from Nanoparticle Assembly: The Functional Whole Is the Sum of Its Parts

由纳米粒子组装制备的磁性 Fe 1.3 Ni 0.7 P 气凝胶：功能整体是其各部分的总和

DOI：
10.1021/acs.jpcc.1c08709
发表时间：
2022
期刊：
The Journal of Physical Chemistry C
影响因子：
0
作者：
Hettiarachchi, Malsha A.;Su’a, Tepora;Ramzan, Ali-hamza;Pokhrel, Shiva;Nadgorny, Boris;Brock, Stephanie L.
通讯作者：
Brock, Stephanie L.

Electrochemical gelation of quantum dots using non-noble metal electrodes at high oxidation potentials