Revestimentos de Fe-Sn como eletrocatalisadores para a reação de desprendimento de hidrogênio

Abstract

Fe-Sn coatings were obtained in choline chloride and ethylene glycol medium in molar ratio 1:2 (ChCl:2EG) on a copper substrate at temperatures of 30 °C and 70 °C produced by control of charge and time on a potential of –1,0 V to investigate the best deposition conditions and their application as electrocatalysts for hydrogen evolution reaction in a alkaline medium for green hydrogen production. SEM analyses indicated compatible morphologies with those presented in the literature, even as the EDS analyses confirmed the presence of both metals in the surface. The XRD patterns show the metallic interphases formation, evidencing the alloy formation. The catalyst tests indicated that the Fe-Sn coatings prove to be efficient in hydrogen production compared to the material used in alkaline electrocatalysts. Finally, it was observed that the Fe97Sn3 electrodeposit revealed the higher catalytical performance with overpotential of 140 mV, Tafel coefficient of 143,1 mV dec–1 and exchange current density of 1.8 × 10–6 A cm–2, beyond presenting a stability considerable when submitted in a continuous test for 120 h.