The Photocatalytic and Photoelectrochemical Properties of Combinatorial Density Gradient TiO2-rGO Nanocomposites Using Hydrothermal Synthesis

• Main Authors: Li-ChunTseng, 曾立君
• Other Authors: Kao-Shuo Chang
• Format: Others
• Language: en_US
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/02346112223067194636

碩士 === 國立成功大學 === 材料科學及工程學系 === 104 === The application of renewable energy has become a global issue in recent years. Semiconductor photocatalyst can effectively decompose organic pollutants and split water to harvest hydrogen fuels by solar light. However, researchers keep exploring the novel materials to overcome nature limitations of materials. In order to efficiently obtain an optimal photocatalyst, a combinatorial composition spread sample was fabricated to facilitate the exploration of appropriate parameters. In this study, density gradient rutile TiO2 was grown on silicon substrate by spin coating and hydrothermal method. Moreover, coupling with density gradient of reduced graphene oxide (rGO) to become a combinatorial density gradient of TiO2-rGO nanorod composites. This novel concept is different from the literature of hydrothermal method which only can produce single parameter on one sample and repeat multiple procedures to explore the best condition. On the contrary, our combinatorial density gradient of TiO2-rGO nanorod composites sample contains a wide range of compositions in a single sample, enabling efficient screening of materials for applications. Various techniques of XRD, SEM, FTIR, Raman, and PL were employed to determine the various characteristics, including phases, morphologies, microstructures, optical properties, compositions, and chemical bondings. Photodegradation activities were determined by decomposing methylene blue (MB) under UV light. The result shows that coupling with suitable amount of rGO can effectively assist TiO2 to enhance the photocatalytic properties. In photoelectrochemical (PEC) reaction, the cell was measured with a constant 1 V bias under UV light. The measured current of TiO2-rGO nanorod composites was approximately 25 μA/cm2 more than double the value obtained from the pure TiO2 nanorods (approximately 10 μA/cm2).