Effect of Gallium addition in platinum electrocatalyst supported on carbon
in the alcohol electrooxidation.
Name: DEISE MENEZES SANTOS
Type: MSc dissertation
Publication date: 07/04/2016
Advisor:
Name |
Role |
|---|---|
| JOSIMAR RIBEIRO | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| DENISE ROCCO DE SENA | External Examiner * |
| JOSIMAR RIBEIRO | Advisor * |
| MARCOS BENEDITO JOSÉ GERALDO DE FREITAS | Internal Examiner * |
Summary: Platinum catalysts supported on carbon are frequently used in the electro-oxidation of alcohols such as ethanol and glycerol into proton exchange membrane fuel cells. The slow kinetics of oxidation of alcohols, the catalyst poisoning and incomplete oxidation products are borders of this technology. The addition of metals into platinum has been widely investigated, though very scarce information about PtGa action in methanol oxidation is reported. In this study, PtGa/C were synthesized by thermal decomposition of the polymeric precursor method to investigate the catalytic activity against the oxidation of ethanol and glycerol. The morphological and electrochemical characterizations were made by: Thermogravimetric analysis, X-ray diffraction, transmission electron microscopy, energy dispersive spectroscopy X-ray, Cyclic voltammetry, chronoamperometry, chronopotenciometry and activation energy test. Morphological characterization showed particles from 7.2 nm to 18.9 nm, solid solution of gallium and platinum, heterogeneous distribution of the particles on the carbon support, platinum on face-centered cubic structure and gallium oxide in the compositions. The unprecedented study of PtGa/C catalytic activity for the electro-oxidation of ethanol and glycerol disclosed in the addition of gallium to platinum increases the catalytic activity and stability compared to pure platinum, according to electrochemical tests.
