Ciclo Semanal de Seminários do CCMC com Ariadne Catto

An investigation of the structural and microstructural properties of Zn1-xCoxO thin films applied as gas sensors

Abstract:  Zinc oxide (ZnO) pure or doped are one of the most promising metal oxide semiconductors for gas sensing applications due the well-known high surface-to-volume area and surface conductivity. It was show that ZnO is an excellent gas-sensing material for different gases. In this context, pure and doped ZnO exhibiting different morphologies and a high surface/volume ratio can be a good option regarding the limitations of the current commercial sensors. Different studies showed that the sensitivity of metal-doped ZnO (e.g. Co, Fe, Mn,) enhanced its gas sensing properties. Motivated by these considerations, the aim of this study consisted on the investigation of the role of Co ions on structural, morphological and the gas sensing properties of nanostructured ZnO samples.  ZnO and Zn1-xCoxO (0 < x < 5 wt%) thin films were obtained via the polymeric precursor method. The sensitivity, selectivity, response time and long-term stability gas sensing properties were investigate when the sample was exposed to different concentration range of ozone (O3), hydrogen (H2) and nitrogen dioxide (NO2) at different working temperatures. The gas sensing property was probed by electrical resistance measurements. The long and short-range order structure around Zn and Co atoms were investigate by X-ray diffraction and X-ray absorption spectroscopy. X-ray photoelectron spectroscopy measurement were performed in order to identify the elements present on the film surface as well as to determine the sample composition. Microstructural characteristics of the films were analyzed by a field-emission scanning electron microscope (FE-SEM).

Seminarista: Adriadne Catto, doutoranda do CCMC

Data e horário: Dia 29/10/2015, quinta-feira, das 10 h às 11 h

Local: Sala 14, Prédio Administrativo do IFSC (embaixo do anfiteatro Prof. Sérgio Mascarenhas)

Amanda Murgo
Sobre Amanda Murgo 134 Artigos
Educadora do Laboratório de Difusão Científica (LaDiC) do Grupo Crescimento de Cristais e Materiais Cerâmicos (CCMC/IFSC/USP) no âmbito das ações de Difusão Científica do CDMF. Assessora de Comunicação do CCMC/LaDiC/CDMF desde 2010. Bacharel em Filosofia pela Universidade Federal de São Carlos com estágio no Projeto "História da Ciência e Meio Ambiente - as demandas por energia através da História" (CCMC/IFSC/USP/CDMF) de abril de 2013 a julho de 2014. Atua ministrando cursos de Educação Ambiental em escolas de Rede Básica de Ensino e Educadores com a temática pelo CDMF até os dias atuais.