An Eco-Friendly Method of BaTiO3 Nanoparticle Synthesis Using Coconut Water

Maria De Andrade Gomes,Zélia Soares Macedo,Alexandre Rocha Paschoal,Lucas Gonçalves Magalhães,Giancarlo Richard Salazar-Banda,Katlin Ivon Barrios Eguiluz,Álvaro Silva Lima

doi:10.1155/2018/5167182

Abstract

BaTiO3 nanoparticles were successfully synthesized by a new coconut water-based sol–gel method using Ba(CH3COO)2 and TiCl3 as the starting salts. The influence of the amount of coconut water and calcination conditions on the barium titanate crystallization was investigated. The resulting nanoparticles were characterized by thermogravimetric and differential thermal analysis, X-ray diffraction, scanning electron microscopy, and Raman and Fourier transform infrared (FTIR) spectroscopies. The ferroelectric tetragonal single phase of BaTiO3 was obtained in samples prepared with a ratio of coconut water volume (mL)/BaTiO3 mass (g) of 25 : 2 and 30 : 2, calcined at 1100°C, which was confirmed by XRD measurements. Crystallites with an average size of about 31 nm for both samples were obtained, and microscopy images revealed the presence of particles in the range of 40 to 60 nm. Raman and FTIR spectra confirmed the dominant tetragonal phase of BaTiO3, meanwhile traces of BaCO3 were identified in FTIR spectra.

Highlights

Barium titanate (BaTiO3—BT) is a well-known ferroelectric material widely used in the manufacture of multilayer ceramic capacitors (MLCCs) [1], thermistors [2], and electrooptic devices [3]
We have developed a green methodology to synthesize barium titanate nanoparticles via a coconut water-based sol–gel route
The produced nanoparticles were characterized by means of simultaneous differential thermal analysis (DTA) and thermogravimetry (TG), X-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy

Summary

Introduction

Barium titanate (BaTiO3—BT) is a well-known ferroelectric material widely used in the manufacture of multilayer ceramic capacitors (MLCCs) [1], thermistors [2], and electrooptic devices [3]. Different wet chemical methods have been employed to produce BaTiO3 nanometer-scale powders including sol–gel, Pechini, sol–emulsion–gel, and solvothermal and coprecipitation methods. These methods allow precursor homogeneity at an atomic level and employ lower calcination temperatures compared with a conventional solid-state method [8]. The BaTiO3 nanoparticles were produced in the presence of sodium hydroxide as a catalyst and oleic acid as a capping agent, using an organometallic compound as a Ti source and n-butanol as a solvent [10] In this way, we have developed a green methodology to synthesize barium titanate nanoparticles via a coconut water-based sol–gel route. The produced nanoparticles were characterized by means of simultaneous differential thermal analysis (DTA) and thermogravimetry (TG), X-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy

Experimental

Results and Discussion

Conclusions