Study of TiOxNy coatings of the photo-electrode of a photoelectrochemical cell applied for hydrogen generation from water

• Grant number: 12/03593-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): July 01, 2012
• Effective date (End): February 28, 2013
• Field of knowledge: Engineering - Electrical Engineering
• Principal Investigator: Rodrigo Savio Pessoa
• Grantee: Wallace Randal de Moura
• Host Institution: Instituto de Pesquisa e Desenvolvimento (IP&D). Universidade do Vale do Paraíba (UNIVAP). São José dos Campos , SP, Brazil
• Associated research grant: 11/50773-0 - Center of excellence in physics and applications of plasmas, AP.TEM

Abstract

In the context of the reduction of fossil energy resources and global warming, much research has been focused on renewable energy sources. The work of scientific initiation presented here is focused on this category since it contributes to the development of a device that stores solar energy in a chemical fuel: hydrogen. This device is based on the photo-electrolysis of water by a photoelectrochemical cell that produces hydrogen and oxygen under the illumination of sunlight. The photoelectrode of this cell will be based on a glass substrate covered with a layer of the transparent conductors (SnO2 doped with fluorine) more a layer of semiconductor thin-film (TiO2 doped with nitrogen). Nowadays, plasma technology arises as an alternative for the processing of thin films because it allows larger process control since it involves many parameters that can be changed to obtain films with different properties, and ensure good reproducibility, unlike what happens in conventional chemical processes. This work aims to study and use TiO2 thin films doped with nitrogen (TiOxNy) as photoelectrode of a photoelectrochemical cell. These will be grown using the reactive magnetron sputtering technique and subsequently characterized by their structure, morphology, and chemistry through the use of x-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy techniques. Moreover, the optical analysis will be performed through the spectrophotometry technique to measure the transmittance and reflectance of the films in order to determine the optical gap of the material. Finally, prototypes will be assembled in photoelectrochemical cells with water-electrolyte and characterized in order to determine their efficiency for generating hydrogen.(AU)