Recently, the increasing level of atmospheric CO<sub>2</sub> has been widely noticed due to its association with global warming, provoking a growth in environmental concerns toward the continued use of fossil fuels. To mitigate the concentration of atmospheric CO<sub>2</sub>, various strategies have been implemented. Among options to turn waste CO<sub>2</sub> into useful fuels and chemicals, carbon capture and utilisation along with renewable hydrogen production as the source materials for methanol production is more preferable. In the 1960s, the highly active and economic Cu/ZnO/Al<sub>2</sub>O<sub>3</sub> catalyst was developed for CO<sub>2</sub> hydrogenation reaction to methanol, since then, metal nanoparticles and nanocomposites have been extensively investigated and applied. Especially, bimetallic catalysts have emerged as an important class of catalysts due to their unique properties and superior catalytic performances compared to their monometallic counterparts. This thesis presents the evolution of the catalyst development for CO<sub>2</sub> hydrogenation to methanol: Firstly, we introduced the CuZn-based catalysts with Zn content increased in the bimetallic CuZn system via a heterojunction synthesis approach. Secondly, we increased the active CuZn sites via introducing ultra-thin layered double hydroxide as the catalyst precursor for methanol production from CO<sub>2</sub> and H<sub>2</sub>. Thirdly, a new class of Rh-In bimetallic catalysts were studied, which shows high methanol yield and selectivity under thermodynamically unfavourable methanol synthesis conditions owing to the strong synergies of Rh-In bimetallic system. Fourthly, for the renewable methanol production from H<sub>2</sub> and CO<sub>2</sub>, the hydrogen source must come from the green production routes. Therefore, an in-depth study of a nanocomposite system, CdS-carbon nanotubes-MoS<sub>2</sub>, for photocatalytic hydrogen production from water has been demonstrated. Finally, the conclusion of this thesis is given and an outlook is presented for the future development in this research area.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:740979 |
| Date | January 2018 |
| Creators | Li, Molly Meng-Jung |
| Contributors | Tsang, Edman |
| Publisher | University of Oxford |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | https://ora.ox.ac.uk/objects/uuid:7e28950e-85e9-4d9a-b791-3f5d1172065e |
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