Development of high-performance Sodium-Ion Batteries and Pseudocapacitors Based on MXene, hard carbons and mixed layered oxides materials

• Grant number: 22/05422-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: June 01, 2022
• End date: November 30, 2022
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Roberto Manuel Torresi
• Grantee: Lenon Henrique da Costa
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 21/00675-4 - Tying up materials for electrochemical energy storage and catalysis, AP.TEM

Abstract

With nanotechnology, new electrode materials have softened the boundaries between electrochemical double-layer capacitors (EDLCs) and batteries based on Na+ or Li+ ion intercalation. Thus, a pseudocapacitive device and a battery can share the same type of negative electrode in different asymmetric configurations, i.e., the same negative electrode combined with a positive high surface area porous electrode (i.e., activated carbon) or a battery-type positive electrode, such as mixed layered oxides derived from abundant elements (i.e., Na, Fe, Mg, and Mn). When compared to lithium-ion batteries (LIBs), electrochemical capacitors present very high cyclability and low energy density. In contrast, sodium-ion batteries (SIBs) present lower energy densities, although of the same order of magnitude, and lower aging aspects, coulomb efficiency, and average working voltage. In this regard, we will explore the boundaries between sodium-ions electrochemical capacitors and batteries. We will produce buckypaper electrodes with good physical and electrochemical properties based on MXene (Ti3C2), carbon materials (e.g., hard carbons and carbon nanotubes) and mixed metal oxides. The electrodes' performance will be studied using electrochemical and physicochemical characterization techniques. Specifically, regarding SIBs, the studies will also be performed via operando Raman spectroscopy, focusing on these devices' energy efficiency and cyclability. We expect the consolidation of new composite materials as negative electrodes of pseudocapacitor devices and SIBs, and positive electrodes of SIBs with higher average working voltages and better aging and cyclability aspects, resulting in safer and more sustainable batteries.