Effect of metallic nanoparticles in catalytic photoelectric properties of hematite electrodes

• Grant number: 19/01977-4
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: June 01, 2019
• End date: January 31, 2020
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Flavio Leandro de Souza
• Grantee: Aryane Tofanello de Souza
• Supervisor: Lionel Vayssieres
• Host Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil
• Institution abroad: International Research Center for Renewable Energy (IRCRE), China
• Associated to the scholarship: 16/01000-2 - Effect of metallic nanoparticles in catalytic photoelectric properties of hematite electrodes, BP.PD

Abstract

Hematite (Fe2O3) photoelectrode is a promising candidate for hydrogen production via water splitting because of its favorable band gap, low cost, and abundance in nature. However, its photoactivity is limited by the poor absorptivity and carrier mobility, slow water oxidation kinetics, and short hole diffusion length. Metallic nanoparticles, such as Au, Cu and Ag, exhibit localized surface plasmon resonances (LSPR) and are well-suitable to improve the optoelectronic properties of hematite, in particular for thin films. Several mechanisms have been proposed to explain the observed LSPR mediated photoelectrochemical performance enhancement. The synergistic effect of the metallic nanoparticle-modified thin hematite photoelectrode combination is an important step to understand how the donor density is increased. However, one of the main problems found it was the comprehension of each mechanisms in interface of metallic nanoparticle-modified hematite/electrolyte for oxygen evolution reaction. In order to clarify the transport properties, the proposal for this internship is to evaluate the photogenerated charges dynamics by transient absorption spectroscopy (TAS), observing the transport mechanism for bare and modified hematite photoelectrodes and the implications at their interfaces. The results achieved will directly applicable to other semiconductors with similar properties to hematite and are expected to be helpful in future design of optimized photoanodes, where, for instance, metal nanoparticle functionalization will be combined with doping and introduction of nanostructured materials. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

TOFANELLO, ARYANE; SHEN, SHAOHUA; DE SOUZA, FLAVIO LEANDRO; VAYSSIERES, LIONEL. Strategies to improve the photoelectrochemical performance of hematite nanorod-based photoanodes. APL Materials, v. 8, n. 4, APR 1 2020. (19/01977-4, 16/01000-2)

TOFANELLO, A.; DIAO, Z.; DJATOUBAI, E.; SU, J. Z.; SHEN, S. H.; SOUZA, F. L.; VAYSSIERES, L.. Engineering hematite/plasmonic nanoparticle interfaces for efficient photoelectrochemical water splitting. Journal of Applied Physics, v. 128, n. 6, AUG 14 2020. (19/01977-4, 16/01000-2)