CAREER: Cation and Nanoparticle Interconversion in Metal-Exchanged Zeolites

职业：金属交换沸石中的阳离子和纳米颗粒相互转化

基本信息

批准号：
2144174
负责人：
Chris Paolucci
金额：
$ 59.73万
依托单位：
University of Virginia Main Campus
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2022
资助国家：
美国
起止时间：
2022-02-15 至 2027-01-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2144174&HistoricalAwards=false
关键词：
CAREER Cation Nanoparticle Interconversion Metal

项目摘要

Small pore, microcrystalline zeolite materials are widely used in the chemicals and fuels industries for processes where molecular-scale capture, separation, or catalytic reaction is needed. In the case of catalysis, zeolites are often used in conjunction with extremely small particles of catalytic metals – or even individual atoms – dispersed throughout the nanoscale pores and voids in the zeolite structure. The resulting catalysts are highly effective for promoting specific catalytic reactions, while efficiently utilizing small amounts of expensive metals such as platinum or palladium. Nevertheless, the harsh conditions associated with many catalytic reactions results in metal particle agglomeration and concomitant loss of catalyst efficiency. The project develops computational molecular models and theory predicting the dynamics of agglomeration and redispersion of metals supported by zeolites. In addition, the models include design and synthesis features that deter the agglomeration of metal atoms and particles under reaction conditions, thus improving the energy efficiency of catalysts widely used for petrochemical and emissions related applications. The project is integrated with efforts that address retention of underrepresented communities at multiple points in the STEM pipeline, through collaboration with local organizations that emphasize coding for girls in K-12, and by organizing events that address social and professional development challenges faced by both international and domestic undergraduate and graduate engineering students. The project develops atomistic models that describe how zeolite composition, gas conditions, and nanoparticle size and distribution affect the thermodynamics and kinetics of cation and nanoparticle interconversion in zeolites. The main objectives are to 1) model the thermodynamics of zeolite-supported platinum and palladium cation and nanoparticle interconversion, 2) predict how catalytically relevant reactant gases promote or impede interconversion, 3) determine how zeolite encapsulation modulates the structure and energy of nanoparticles, and 4) determine the fundamental processes that govern the kinetics of interconversion between cations and nanoparticles. These objectives will be fulfilled by using molecular modeling tools that include density functional theory, wave function theory, classical forcefields, and Monte Carlo simulations. This project will provide guidance on the engineering of deactivation resistant zeolites, a challenge at the frontiers of catalysis and zeolite synthesis. Further, the project will enable transformative predictions of zeolite compositions and synthetic strategies that stabilize catalyst performance in the reaction environment.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.

小孔，微晶沸石材料被广泛用于化学物质和燃料工业中，用于需要分子尺度捕获，分离或催化反应的过程。在催化的情况下，沸石通常与极小的催化金属颗粒（甚至是单个原子）结合使用，分散在整个纳米级孔中，沸石结构中的空隙。所得的催化剂对于促进特定的催化反应非常有效，同时有效地利用了少量昂贵的金属（例如铂或钯）。然而，与许多催化反应相关的有害条件导致金属颗粒聚集和伴有催化剂效率的丧失。该项目开发了计算分子模型和理论，可预测沸石支持的金属的聚集动力学和重新分散。此外，这些模型还包括设计和合成特征，这些特征决定了在反应条件下金属原子和颗粒的聚集，从而提高了广泛用于石化和排放相关应用的催化剂的能效。该项目与努力相结合，以解决STEM管道中多个要点的保留人数不足的社区，通过与当地组织的合作，这些组织强调为K-12中的女孩编码编码，并通过组织活动，以解决国际和家庭培训生长和研究生工程学生面临的社会和专业发展挑战。该项目开发了原子模型，这些模型描述了沸石组成，气体条件和纳米颗粒的大小和分布如何影响沸石中阳离子和纳米粒子互转换的热力学和动力学。主要目标是1）模拟沸石支持的铂和钯阳离子和纳米颗粒互连的热力学，2）预测如何促进相关的反应物质促进或促进相互转换，3）确定Zeolite封装如何调节纳米颗粒的结构和能量之间的纽约纳米的结构和能量。和纳米颗粒。这些目标将通过使用包括密度功能理论，波浪函数理论，经典力场和蒙特卡洛模拟的分子建模工具来实现。该项目将提供有关抗活沸石的工程的指导，这是在催化和沸石合成边界的挑战。此外，该项目将实现对沸石组成和稳定反应环境中催化剂性能的合成策略的变革性预测。该奖项反映了NSF的法定任务，并被认为是通过基金会的智力优点和更广泛的影响来通过评估来获得的支持。