Amine-functionalised Cu/ZnO photocatalyst for efficient CO2 reduction

• Main Author: Toh, Hui Ying
• Other Authors: Xue Can
• Format: Final Year Project
• Language: English
• Published: 2016
• Subjects: DRNTU::Engineering::Materials::Nanostructured materials
• Online Access: http://hdl.handle.net/10356/66467
• Institution: Nanyang Technological University

As the issues of depletion of natural fuel sources and the harms of excessive carbon dioxide in the atmosphere are being raised more frequently over the years, it has led to more resources being dedicated to develop efficient means of converting CO2 into usable solar fuels and at the same time reduce atmospheric CO2 content. This study aims to contribute to this area of concern by modifying photocatalyst to improve their CO2 photoreduction ability. For this report, amine-functionalised Copper (I) coated Zinc Oxide nanostructure is the main subject of study. It is being studied against ZnO-based catalysts that are unmodified or modified with either Cu or amine. These samples was synthesized by hydrothermal method, and UV-vis photodeposition of Cu when necessary. Characterisation was done by performing FTIR to study the bonds composition, and amine was found to be successfully loaded onto ZnO. Further XPS test was carried out to confirm the presence and state of Cu (I). Then, XRD and UV-vis spectrometry results were also discussed to gather information of the crystalline structure and light absorption ability. Finally, the results collected from gas chromatography of gas evolved during CO2 reduction test were extensively analysed and discussed. This study reveals that amine-functionalised Zinc oxide nanostructures coated with copper has improved ability when used as a photocatalyst to reduce CO2 into useful solar fuels. CO2 reduction rate is boosted due to amine group promoting chemisorption for CO2 capture which increases CO2 affinity with ZnO surface ions, and also presence of Cu2O/ZnO heterojunction that prevents the recombination of photogenerated charge carriers that play a key role in the reduction process.