NER: Perovskite Reservoirs for Precious Metal Nanoparticles

建议标题：“NER”贵金属纳米粒子的钙钛矿库建议编号：CTS-0508455首席研究员：苏珊娜·L·斯科特研究所：加州大学圣巴巴拉分校分析(决策的基本原理)：该项目旨在探索制造贵金属纳米粒子的新范式。纳米颗粒以分解的形式存储在复杂的氧化物储存库中，作为分散的金属离子，响应于特定的环境刺激，在储存库的表面自发和可逆地产生。当不使用时，它们会恢复到存储形式，从而显著延长寿命并稳定粒子生长。这一现象的理论基础将得到发展，特别关注混合氧化物结构稳定贵金属离子和促进其流动性的能力。用于处理钙钛矿结构和金属-氧化物界面的新的密度泛函方法将被应用于实际结构和假想结构，由此产生的预测将通过合成和表征材料来进行实验验证。这些材料的一个直接应用是催化，与它们的块状金属对应物相比，贵金属纳米颗粒具有不同寻常的反应性和选择性。虽然这种纳米粒子可以很容易地通过传统方法制备，但在反应条件下它们很快就会失去催化活性。从储存库中产生和再生纳米粒子的能力避免了复杂的合成需要，最大限度地提高了催化剂的生产率，延长了活性，促进了金属回收，并最终防止了纳米材料对环境的污染。如果这种现象能够被证明是普遍的，它可能会给催化领域带来革命性的变化，使实现所需转变所需的贵金属数量减少数量级。考虑到纳米催化剂的成本和稀缺性，这种对自然资源的智能利用可以使纳米催化剂在燃料电池等应用中得到广泛采用。一个研究和教育的合作项目将在两个机构进行。一个创新的宾夕法尼亚州科学教师学院将参与其中，一个夏季研讨会将是加州纳米系统研究所K-12计划的一部分。

AbstractProposal Title: "NER" Perovskite Reservoirs for Precious Metal NanoparticlesProposal Number: CTS-0508455Principal Investigator: Susannah L. ScottInstitution: University of California - Santa BarbaraAnalysis (rationale for decision):The project is designed to explore a new paradigm for manufacturing precious metal nanoparticles. Stored in disassembled form as dispersed metal ions in a complex oxide reservoir, the nanoparticles are generated spontaneously and reversibly at the surface of the reservoir in response to a specific environmental stimulus. When not in use, they revert to the stored form, which results in dramatically prolonged lifetimes and stabilization against particle growth. The theoretical basis for this phenomenon will be developed, paying particular attention to the ability of mixed oxide structures to stabilize precious metal ions and to promote their mobility. New density functional methods for treating perovskite structures and metal-oxide interfaces will be implemented for both real and hypothetical structures, and the resulting predictions will be tested experimentally by synthesizing and characterizing materials. An immediate application for these materials exists in catalysis, where nanoparticles of precious metals possess unusual reactivity and selectivity compared to their bulk metal counterparts. Although such nanoparticles can be readily prepared by conventional methods, they rapidly lose their catalytic activity under reaction conditions. The ability to generate and regenerate nanoparticles from a reservoir avoids the need for complex syntheses, maximizes catalyst productivity, prolongs activity, facilitates metal recovery, and ultimately prevents environmental contamination by the nanomaterials. If the phenomenon can be shown to be general, it could revolutionize the field of catalysis, decreasing by orders of magnitude the amounts of precious metal required to achieve desired transformations. Given their expense and rarity, this intelligent use of a natural resource could enable widespread adoption of nanocatalysts in applications such as fuel cells. A collaborative program of research and education will be performed at two institutions. An innovative Pennsylvania Science Teachers Institute will be involved, and a summer workshop will be part of the California Nanosystems Institute's K-12 program.