The University of Southampton
University of Southampton Institutional Repository

Zeolite supported platinum electrocatalysts

Zeolite supported platinum electrocatalysts
Zeolite supported platinum electrocatalysts

Recently, platinum exchanged zeolite modified catalysts have been shown to be interesting as electrodes, as the physical structure and chemical nature of the zeolite may influence the electron transfer at the electrode - solution interface of known chemical steps. Generally, the catalytic nature of zeolite can be modified by pre-exchanging metal ions to give the desired cationic form, and its catalytic activity can be increased by calcinating to lock the exchangeable metal ions into position.

In this project we have chosen Y zeolite as Pt support. The study found that the pretreatment such as, preparation methods, Pt(NH3)4(NO3)2 or Pt(NH3)4(NO3)2/NH4NO3 ion exchange and impregnation methods, calcination and reduction temperature and the stoichiometry of the titration method (O2, H2), is important for obtaining highly dispersed platinum-zeolite catalysts. The structure/reactivity relationship was investigated by altering the Pt loading from 1.5wt.% to 5wt.% to show that the particle size increases with the metal loading. The investigation was carried by the use of X-ray absorption spectroscopy and in particular the extended X-ray adsorption fine structure (EXAFS) method. XAS data was collected in a gas treatment cell as well as in the electrochemical environment.

The materials are characterised by fabricating carbon composite electrodes, and the electrocatalytic activity is determined by cyclic voltammetry technique. We used the evidence of hydrogen adsorption in the cyclic voltammograms as the basis upon which to make the judgement. The experimental results show that the Pt nanoparticle supported on zeolite may be electrochemically reduced due to the hydrogen spillover function of the zeolite.

Based on the experimental results, we found that the use of the Pt(NH3)4(NO3)2/NH4NO3 ion exchanged material, subjected to oxygen calcination - hydrogen reduction performs better than other catalysts prepared for a variety of electrochemical reactions.

University of Southampton
Yao, Jun
cd8e4e0e-ed2d-4590-be1f-fc6340f6a441
Yao, Jun
cd8e4e0e-ed2d-4590-be1f-fc6340f6a441

Yao, Jun (2002) Zeolite supported platinum electrocatalysts. University of Southampton, Doctoral Thesis.

Record type: Thesis (Doctoral)

Abstract

Recently, platinum exchanged zeolite modified catalysts have been shown to be interesting as electrodes, as the physical structure and chemical nature of the zeolite may influence the electron transfer at the electrode - solution interface of known chemical steps. Generally, the catalytic nature of zeolite can be modified by pre-exchanging metal ions to give the desired cationic form, and its catalytic activity can be increased by calcinating to lock the exchangeable metal ions into position.

In this project we have chosen Y zeolite as Pt support. The study found that the pretreatment such as, preparation methods, Pt(NH3)4(NO3)2 or Pt(NH3)4(NO3)2/NH4NO3 ion exchange and impregnation methods, calcination and reduction temperature and the stoichiometry of the titration method (O2, H2), is important for obtaining highly dispersed platinum-zeolite catalysts. The structure/reactivity relationship was investigated by altering the Pt loading from 1.5wt.% to 5wt.% to show that the particle size increases with the metal loading. The investigation was carried by the use of X-ray absorption spectroscopy and in particular the extended X-ray adsorption fine structure (EXAFS) method. XAS data was collected in a gas treatment cell as well as in the electrochemical environment.

The materials are characterised by fabricating carbon composite electrodes, and the electrocatalytic activity is determined by cyclic voltammetry technique. We used the evidence of hydrogen adsorption in the cyclic voltammograms as the basis upon which to make the judgement. The experimental results show that the Pt nanoparticle supported on zeolite may be electrochemically reduced due to the hydrogen spillover function of the zeolite.

Based on the experimental results, we found that the use of the Pt(NH3)4(NO3)2/NH4NO3 ion exchanged material, subjected to oxygen calcination - hydrogen reduction performs better than other catalysts prepared for a variety of electrochemical reactions.

Text
843013.pdf - Version of Record
Available under License University of Southampton Thesis Licence.
Download (14MB)

More information

Published date: 2002

Identifiers

Local EPrints ID: 464706
URI: http://eprints.soton.ac.uk/id/eprint/464706
PURE UUID: d8884eba-8f6a-45bc-b990-b018a8b4a826

Catalogue record

Date deposited: 04 Jul 2022 23:57
Last modified: 05 Jul 2022 02:59

Export record

Contributors

Author: Jun Yao

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×