Synthesis and characterization of heterostructures based on SLG/Mo/Sb2Se3/CdS/ZnO/cocatalyst for photoelectrocatalytic applications

• Grant number: 21/07727-0
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: November 01, 2021
• End date: July 31, 2022
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Lucia Helena Mascaro Sales
• Grantee: Magno Barcelos Costa
• Supervisor: Edgardo Saucedo Silva
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: Universitat Politècnica de Catalunya (UPC), Spain
• Associated to the scholarship: 17/21365-8 - Electrodeposition and characterization of Sb2Se3 and MSbxSey (M = Cu, Co, Ni, or Zn) thin films for applications in the hydrogen production and CO2 reduction., BP.DR

Abstract

Recently, unrestrained industrial and population growth have brought problems directly related to the significant increase in energy consumption. Approximately 85% of this consumption comes from the burning of fossil fuels, resulting in a large amount of CO2 released into the atmosphere and boosting the greenhouse effect and climate change. Therefore, the lack of use of renewable or sufficiently clean energy sources is a real problem and the search for sustainable development is a challenge in modern research. In this scenario, solar energy has gained huge attention because it is a clean and inexhaustible alternative, whose radiation can be harnessed in different ways. One of them is the chemical energy, where two of its main purposes are strongly highlighted: the process of water photoelectrolysis into H2(g) - a powerful and clean fuel - and the photoelectrochemical reduction of CO2 to industrial interest compounds - a promising form of CO2 recycling. As materials developed for this application, there was a resurgent interest in low toxicity, earth-abundant, and low-cost semiconductors. Therefore, binary and ternary copper-based chalcogenides, for example, Sb2Se3 and CuSbSe2, respectively, are considered important semiconductors because they have shown good photovoltaic and photoelectrochemical properties. Additionally, according to studies associated with the hydrogen evolution reaction catalysis, compounds with Co, Ni and Zn have also shown positive photoactivity results. Due to these circumstances, the present work proposes the obtaining of Sb2Se3 and MSbxSey (M = Cu, Co, Ni, or Zn, for doped and ternary systems) employing electrodeposition in the formation of photocathodes applied to the production of hydrogen or CO2 reduction. The films will be characterized in terms of their morphology, composition, and crystalline structure by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction techniques, respectively; UV-Vis and electrochemical impedance spectroscopy will be used to characterize optoelectronic properties, while the photocurrent of the films will be evaluated utilizing photoelectrochemical characterization, both in the absence and in the presence of Pt, MoS2 and WS2 catalytic nanoparticles decorated on the films' surfaces. Finally, an electrode of configuration Sb2Se3(or MSbxSey)/CdS/ZnO/catalytic nanoparticles will be fabricated and tested in the hydrogen production or reduction of CO2 reactions. (AU)