EAGER: Laser Condensation of Graphene/Silicon Nanocomposites for Enhanced Electrochemical Properties

基于石墨烯的复合材料(石墨烯和纳米颗粒的组合)正被广泛应用于场效应晶体管、传感器、超级电容器、太阳能电池、锂离子电池、光催化剂和光导体。然而，石墨烯复合材料的性能往往受到高度无序的微观结构、纳米颗粒的聚集以及石墨烯和纳米颗粒之间松散连接的界面的困扰。这一早期概念探索性研究资助(AGER)项目旨在阐明通过受控激光加工在电池应用中增强石墨烯/硅纳米复合材料电化学性能的潜在机制。激光辅助的合成研究将得到理论建模的补充，该理论模型试图预测观察到的行为。与该项目相关的教育活动侧重于通过普渡大学的女性工程项目协调针对中学生的电池技术实践推广活动。本研究的总体目标是通过激光加工制造石墨烯/硅纳米复合材料，并通过原子建模和电化学测试了解其电化学行为。激光处理的石墨烯/硅纳米颗粒在机械稳定性、材料均匀性以及石墨烯/纳米颗粒界面的低接触电阻等方面具有优势。为了对激光加工及其产生的特性有一个基本的了解，该研究计划有两个主要目标。第一个目标是通过实验和建模来研究激光处理纳米复合材料的界面工程。第二个目标是通过性能测试了解石墨烯/硅纳米复合材料的电化学行为，如充放电循环稳定性和倍率性能。本研究将确定提高石墨烯/硅纳米复合材料电化学性能的最佳工艺条件。从这项工作中获得的知识将有助于石墨烯基纳米复合材料的制造，并有助于储能材料的发展。

Graphene-based composites (combinations of graphene and nanoparticles) are being adopted for versatile applications in field-effect transistors, sensors, supercapacitors, solar cells, Li-ion batteries, photocatalysts, and photoconductors. However, the performance of graphene composites is often plagued by the highly disordered microstructure, aggregation of nanoparticles, and loosely connected interfaces between graphene and nanoparticles. This EArly-concept Grant for Exploratory Research (EAGER) project seeks to elucidate the underlying mechanisms of enhanced electrochemical properties of graphene/silicon nanocomposites in their battery application through controlled laser processing. The laser assisted synthetic study will be complemented by theoretical modeling that seeks to predict the observed behavior. The educational activities associated with this project focus on hands-on outreach activities for middle school students on battery technology, coordinated through the Women in Engineering program at Purdue University.The overall goal of this research is to manufacture graphene/silicon nanocomposites by laser processing and understand the electrochemical behavior through atomistic modeling and electrochemical tests. Laser processed graphene/silicon nanoparticles display advantages in mechanical stability, material uniformity, and low contact resistance at graphene/nanoparticle interfaces. To develop a fundamental understanding of laser processing and the resulting properties, the research plan has two major objectives. The first objective is to study the interfacial engineering of laser processed nanocomposites through experiments and modeling. The second objective is to understand the electrochemical behaviors of graphene/silicon nanocomposites by performance tests, such as charging/discharging cycle stability and rate performance. The research will determine the optimum processing conditions for the enhanced electrochemical performance of graphene/silicon nanocomposite. The knowledge gained from this work will facilitate the manufacture of graphene based nanocomposites and contribute to the development of energy-storage materials.