Nanohíbridos de manganês e enxofre: melhora de propriedades redox para aumento da capacidade de armazenamento de energia

• Autor(a) principal: FERREIRA , Raissa Soares Penha
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFMA
• Texto Completo: https://tedebc.ufma.br/jspui/handle/tede/tede/5000
• topic: armazenamento de energia;; manganês e enxofre;; nanohíbridos;; energy storage;; manganese and sulfur;; nanohybrids.; Eletroquímica

This work aims to develop a simple and effective methodology for synthesizing 1D nanomaterials (nanowires) of manganese oxides that will serve as a template for forming nanohybrids with sulfur. The central idea is to produce cheap and stable materials for applications in pseudo-supercapacitors. As these devices aim to store a large number of electrical charges, accumulating an internal imbalance of charges, materials with controlled size, shape, and composition can be used to modulate the efficiency of the devices. The results obtained so far show, through microscopy, that the nanowires were successfully obtained and that although structural modifications occurred after sulfur insertion, the longitudinal aspect, important for charge-discharge applications, was maintained. In addition, some indications show that the materials incorporated sulfur in their structure. The best electrode was the 70% MnO2-S due to the high electrochemical activity and capacitance values, which were 807.5, 655, 560, 495, 440, and 425 F g-1 at current densities of 1, 2, 4, 6, 8, and 10 A g-1 . Still, the electrode retained 52.63% of the initial capacitance, which is a promising result for the area