UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Designing metal nanoparticles for catalysis

Rogers, SM; (2017) Designing metal nanoparticles for catalysis. Doctoral thesis , UCL (University College London). Green open access

[thumbnail of Scott Rogers thesis.pdf]
Scott Rogers thesis.pdf

Download (12MB) | Preview


The sol-immobilisation method, in which metal nanoparticles are ‘preformed’ (stabilised by the polymer, polyvinyl alcohol) before they are anchored to a support material, was adapted in order to prepare monometallic Au/TiO2 and Pd/TiO2 catalysts, with tailored properties. Varied temperature and solvent environments (H2O, mixed H2O:EtOH and EtOH) were employed during colloidal metal formation, generating metal particles with distinct characteristics (metal particle diameter and available metal sites). The metal nanoparticle properties in the resulting catalysts were fully characterised using a range of spectroscopic (XAFS, IR and UV-Vis) and imaging techniques (TEM and HAADF STEM). It was determined that the preparation of metal nanoparticles at −30°C, in a mixed H2O:EtOH solvent afforded the smallest average particle diameter, regardless of the choice of metal (2.0 nm for Au, 1.4 nm for Pd). However, when prepared at 1°C in H2O, a higher population of small Au (< 5 atoms) or Pd clusters (< 20 atoms) existed, compared with any other environment. The performance of the catalysts were tested in three different reactions; Au/TiO2 for the oxidation of glycerol, and Pd/TiO2 for the hydrogenation of furfural and pnitrophenol. For the two former reactions, it was established that metal particle size is not the only factor influencing performance; the highly active isolated metal clusters, as well as the solvent-PVA-metal interaction, are considered very important factors, and are discussed. Understanding colloidal metal formation, including nucleation and growth phenomena, is vital in the future design of metal nanoparticle properties, and was investigated by means of in situ XAFS. A continuous flow method of nanoparticle synthesis was first explored and developed, before a synchrotron based experiment was performed to monitor the nanoparticle generation (colloidal reduction) in a range of reactors fabricated from different materials (silicon/glass, PTFE and PEEK).

Type: Thesis (Doctoral)
Title: Designing metal nanoparticles for catalysis
Event: UCL
Open access status: An open access version is available from UCL Discovery
Language: English
UCL classification: UCL > Provost and Vice Provost Offices
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Chemistry
URI: https://discovery.ucl.ac.uk/id/eprint/1560408
Downloads since deposit
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item