Discipline: Nanoscience
Subcategory: Nanoscience
Juan C. Arango - Universidad del Turabo
Co-Author(s): Sergio Pinilla, Department of Applied Physics, Universidad Autónoma de Madrid, Madrid Spain; Carmen Morant Department of Applied Physics, Universidad Autónoma de Madrid, Madrid Spain, Loraine Soto, Materials Characterization Center Inc. San Juan Puerto Rico; Edgard Resto Materials Characterization Center Inc. San Juan Puerto Rico, Francisco Márquez, Nanomaterials Research Group, Universidad del Turabo, Gurabo Puerto Rico
Silicon, with a specific capacity of ~4200mAh/g, is considered as the most promising candidate to be used as anode material for lithium-ion batteries (LIBs). Among its good features, silicon is abundant, has low work potential, and has a high theoretical specific capacity, which is more than ten times higher than that of graphite (commercial anode). However, silicon undergoes an enormous change in volume (ca.275%) during the lithiation/de-lithiation processes, resulting in a disintegration of the material, and subsequent electrical disconnection. Carbon nanotubes (CNTs), are outstanding nanostructures, widely studied for LIBs anodes, because of its conductive and mechanical properties. In this research, silicon nanowires (SiNWs) were synthetized through a Metal Assisted Chemical Etching (MACE) approach, reaching high crystallinity and purity nanostructures suitable for LIBs. After that, commercial CNTs (RhenofitCNT-4) were added in various percentages to obtain mixtures of SiNWs/CNTs. Finally, each mixture was ultra-sonicated for 8 minutes to ensure a homogeneous material dispersion, and vacuum-filtered to deposit the nanostructures in the filter surface and obtain membrane-like structures usable as free-standing anodes suitable for LIBs. Because of the CNTs presence in the mixture, these material is quite flexible and resistant. In addition, the physical framework formed by the CNTs around SiNWs will help accommodate the mechanical strain caused during the lithiation-delithiation process in LIBs. The characterization of the material was carried out by scanning electron microscopy (SEM), Raman spectroscopy and energy dispersive X-ray spectroscopy (EDX). The material will be used as electrode in the manufacture of coin cells to measure their electrochemical behavior.
Not SubmittedFunder Acknowledgement(s): The Department of Energy through the Massie Chair project, for funding this project. The Puerto Rico Energy Center (PREC). The Materials Characterization Center Inc. The Department of Applied Physics and Instituto Nicolás Cabrera at Universidad Autónoma de Madrid. CRANN and AMBER research centers, Trinity College Dublin, Dublin Ireland.
Faculty Advisor: Francisco Márquez, fmarquez@suagm.edu
Role: The syntheses, anode customization and batteries assembly processes had been performed by myself. In addition part of the SEM characterization process.