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 realproblem 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 to this application, there was a resurgent interest in low toxicity, earthabundant, 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 to 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) by means of 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 optoelectronicproperties, while the photocurrent of the films will be evaluated by means of photoelectrochemical characterization, both in the absence and in the presence of Pt, MoS2and WS2 catalytic nanoparticles decorated on the films' surfaces. Finally, an electrode ofconfiguration Sb2Se3(or MSbxSey)/CdS/ZnO/catalytic nanoparticles will be fabricated and tested in the hydrogen production or reduction of CO2 reactions.
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