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| Author(s): |
Vítor Mendes Miguel
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ) |
| Defense date: | 2021-08-02 |
| Examining board members: |
Susana Ines Cordoba de Torresi;
Luiz Henrique Dall'Antonia;
Claudia Longo
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| Advisor: | Susana Ines Cordoba de Torresi |
| Abstract | |
MnO2 is a cheap and versatile material, being able to act as a catalyst for different electrochemical reactions. The addition of small amounts of Au nanoparticles, enables the possibility to explore the localized surface plasmon resonance (LSPR) effect to improve the electrochemical properties of MnO2. The LSPR effect can accelerate several reactions under visible light irradiation, improving the charge separation and light harvesting properties of the semiconductors. Here, by employing MnO2 nanowires decorated with Au NPs (MnO2-Au), it was demonstrated that MnO2 catalytic activity can be greatly improved by the LSPR in a hybrid system. The catalytic properties of the semiconductor were demonstrated for the H2O2 oxidation as a model reaction. A clear increase in H2O2 oxidation current was verified for the gold decorated nanowires under visible light irradiation, with an increase of 116 % in the sensitivity compared with dark conditions. Mechanistic analysis indicates that the increased performance was related to a more efficient charge separation by plasmonically generated hot electrons and holes. The results reported herein provide an approach to achieve an improved light harvesting and performance in the visible range of the spectrum for semiconductors, inspiring the use plasmonic heterostructures towards electrocatalysis. (AU) | |
| FAPESP's process: | 19/15885-4 - Plasmon study of the application of MnO2/Au nanoparticles as an electrochemical sensor for H2O2 by an electrostatic layer-by-layer deposition method |
| Grantee: | Vítor Mendes Miguel |
| Support Opportunities: | Scholarships in Brazil - Master |