Efeito do pH nas propriedades estruturais e elétricas do Titanato de Sódio Sintetizado via Sonoquímica para aplicação em componentes de baterias

Abstract

With the increasing need to use renewable energy sources, energy storage provision becomes indispensable. Batteries play a fundamental role as energy storage devices, widely used in portable devices and electric vehicles. However, lithium-ion batteries, which are currently popular, present challenges related to the scarcity and cost of raw materials, as well as issues of toxicity and flammability. In the face of these problems, various efforts have been directed towards the development of alternative materials for the composition of these devices. In this regard, Sodium Titanates, particularly the Na2Ti6O13 and Na2Ti3O7 phases, have demonstrated promising characteristics such as thermal and chemical stability, charge density, and ionic conductivity, making them a potential alternative to address energy-related issues. However, these characteristics need to be improved to make their application viable and economically competitive. The objective of this work is to enhance the electrical properties of Sodium Titanate through pH control after material synthesis. The samples were synthesized using the Sonochemical method. An HCl solution was used to adjust the pH and produce the pH14, pH12, pH10, pH8, and pH6 samples, which were named according to their respective pH values. These samples were used to evaluate the effect of pH on the structural and electrical properties of Sodium Titanate. X-ray Diffraction (XRD) technique was employed for the structural characterization of the material, while Fourier Transform Infrared Spectroscopy (FTIR) was used to analyze the vibrational bands. Furthermore, Complex Impedance Spectroscopy (CIS) was employed to assess the electrical properties. The XRD results indicated that the desired phases were obtained, and the FTIR showed characteristic bands of titanates, while CIS demonstrated that pH adjustment resulted in improvements in the electrical behavior.