Amine fuctionalized zinc oxide for photocatalytic carbon dioxide reduction
Lee, Wan Jun
Date of Issue2015
School of Materials Science and Engineering
Global warming, affected by the increase in carbon dioxide concentration, is becoming a worrisome trend in the world today due to industrialization and the use of fossil fuels for energy consumption. Hence, an ideal strategy to solve the two problems of global warming and fossil fuel scarcity at once is to remove carbon dioxide concentration by the photocatalytic conversion of carbon dioxide into hydrocarbons as a sustainable source of fuels. In this experiment, zinc oxide, a semiconductor with a high energy gap with high binding energy, was used as a photocatalyst. As amine has high interaction with carbon dioxide, amine functional groups were attached to the surface of zinc oxide to increase the capture of carbon dioxide so that photocatalytic reduction of carbon dioxide could be improved. This experiment aims to create an amine functionalized zinc oxide and find out whether the amine group on zinc oxide can effectively capture CO2 for photocatalytic conversion into hydrocarbon fuels and also to find out the capability in increasing the product yield. FTIR, XRD and photocatalytic reduction of carbon dioxide were used to analyse the different samples of zinc oxide (ZnO) and monoethanolamine-zinc oxide (MEA-ZnO). The samples were indexed to the wurtzite ZnO structure. Even though MEA was successful in attaching onto the surface on the zinc oxide through the hydrothermal reaction at 90°C for 12 hours, very small amount of products were produced. However, it has been found that an increase in concentration of monoethanolamine will result in an increase in production of methane while the production of carbon monoxide were comparable for the different samples. Therefore, efficiency of the photocatalytic reduction of CO2 should be improved and this could be done by adjusting other parameters of the experiment. Parameters like increasing the temperature of autoclave or increasing the MEA concentration or using even stronger light intensities could be changed to find out if the efficiency will be affected.
Final Year Project (FYP)
Nanyang Technological University