Loading Cuprous Oxide on 2-Dimensional Graphitic Nanosheets for Photocatalytic Reduction of CO2
| Autor: | CHANG, PO-YA, 張博雅 |
|---|---|
| Rok vydání: | 2019 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 107 In few decades, the major factor of climate change is carbon dioxide emission. Moreover, the energy demand for human activity raise with years. Turing carbon dioxide to fuel or valuable product solve not only excessive carbon dioxide emission, but also meet the energy demand. Photocatalytic carbon dioxide is a clean way without extra energy consumption. We will study in 2D graphitic structure loading cuprous oxide for photocatalytic carbon dioxide. This study divides two parts: (1) 2D graphitic structure loading cuprous oxide Compare the photocatalytic activity among hydrothermal treated graphene oxide(h-GO), nitrogen doped graphene oxide (NGO), and graphitic carbon nitride(gCN). The spin trap technique results present the series of h-GO generated higher DMPO-OH signal under visible illumination. From the result of photocatalytic carbon dioxide in gas system, NGO/p-Cu2O performed the highest conversion rate. However, the gCN series shows low photocatalytic activity. We will investigate in next chapter. (2) Graphitic carbon nitride loading cuprous oxide with various shapes Submicron cuprous oxide (Cu2O) crystals with various morphologies were successfully fabricated and incorporated with graphitic carbon nitride (gCN) to evaluate their activity for gas phase CO2 photoreduction under visible-light illumination. Both the morphology of Cu2O and the composition of copper species were tunable and were significantly affected by the presence of gCN. The morphology of Cu2O influenced the band structure and optical property, as well as the efficiency of photo-induced charge transfer within each sample. In addition to the majority of Cu2O crystals, other copper species, CuO or metallic Cu, were presented and considered as the assistance for CO2 adsorption or interfacial charge transfer. Improved conversion of CO2 to CO was achieved by combining n-type gCN and p-type Cu2O crystals with an optimum surface composition. Adjusting the content of gCN in photocatalyst affects the photocatalytic CO2 reduction results, which has an optimum ratio. In photocatalytic CO2 reduction system, adding 95% ethanol as sacrificial reagent enhanced the photocatalytic activity. The photoenergy conversion efficiency increase about 20000 times in maximum. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|