Journal of Nanomedicine & Nanotechnology

Graphene and Titanium dioxide based hybrid materials as photoelectrocatalytic systems

7^th World Nano Conference

June 20-21, 2016 Cape Town, South Africa

Rodrigo Segura, Fernanda Olivares, Ricardo Henriquez and Patricio Haberle

Universidad de Valparaíso, Chile
Universidad Técnica Federico Santa María, Chile

Scientific Tracks Abstracts: J Nanomed Nanotechnol

Abstract:

Graphene layers represent a good candidate to develop composed photocatalysts. Due to its high electronic conductivity, it can prevent the recombination of the electron-hole pair and act as a doping agent and even extend the range of light absorption of a semiconductor such as the TiO2. In this contribution, thin TiO2 layers were grown on few layers graphene (FLG) in order to prepare hybrid photocatalysts with the properties of both materials. FLGs were synthesized by chemical vapor deposition (CVD) at 1000°C using acetylene as carbon source and copper as substrate. After synthesis, the FLGs were transferred to silicon substrates and TiO2 layers were deposited on FLG by decomposition of titanium tetraisopropoxide in a CVD system. The photocatalytic performances of these materials were evaluated by measurements of photocurrent in a 3-electrode cell assembly by using a solar simulator and a potentiostat. The photocurrent results show that the FLG is very electroactive presenting a similar behaviour under both dark and illumination; on the other hand the TiO2 layers grown over silicon show the typical behaviour of a photoactive semiconductor since these samples exhibit a raise in the current with the applied potential only when it is illuminated. The hybrid Si-FLG-TiO2 material present in principle a similar behaviour of Si-FLG but when we made a chronoamperometry alternating dark and light cycles discounting the dark response, it is possible to observe a similar performance than Si-TiO2 sample. Both materials, graphene and titanium dioxide have preserved their properties after the assembly.

Biography :

Rodrigo Segura received his PhD degree in Chemistry at the Universidad de Concepción in 2004. Since 2009, he is Professor of Inorganic Chemistry in the Institute of Chemistry and Biochemistry at the Universidad de Valparaíso. His main fields of research encompass Synthesis, Characterization and Properties of Nanomaterials. In the recent years, he has been devoted to the study of carbon nanostructures, specially the synthesis of carbon nanotubes alloyed with metal and semiconductor nanoparticles for sensing and energy applications.

Email: rodrigo.segura@uv.cl