Electrocatalysis of Oxygen Evolution Reaction by Iron Oxide Nanomaterials Synthesized with Camellia sinensis Extract

The generation of clean, zero-carbon, and renewable energy is a challenge for the development of a sustainable and egalitarian society. Hydrogen gas can be produced by water electrolysis and has been claimed as the most promising option to replace fossil fuels. The oxygen evolution reaction (OER) is...

Full description

Saved in:

Bibliographic Details
Published in:	Journal of the Brazilian Chemical Society Vol. 35; no. 11
Main Authors:	Machado, Samara L., Silva, Ana Luisa, Souza, Ana Paula N. de, Sánchez, Dalber R., Alzamora, Mariella, Gois, Jefferson S. de, Carvalho, Nakédia M. F.
Format:	Journal Article
Language:	English Portuguese
Published:	Sociedade Brasileira de Química 01-11-2024
Subjects:	CHEMISTRY, MULTIDISCIPLINARY oxygen evolution reaction iron oxide renewable energy plant extract electrocatalysis black tea
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	The generation of clean, zero-carbon, and renewable energy is a challenge for the development of a sustainable and egalitarian society. Hydrogen gas can be produced by water electrolysis and has been claimed as the most promising option to replace fossil fuels. The oxygen evolution reaction (OER) is the most energetically demanding step of the water splitting and requires the use of electrocatalysts to overcome the kinetic barrier. Iron oxide nanomaterials have been emerging as a low-cost and Earth-abundant OER electrocatalysts. The synthesis of iron oxide assisted by plant extract is an eco-friendly approach to obtain nanomaterials with unique properties. Herein, we investigated iron oxide synthesized with the assistance of Camellia sinensis extract, under different experimental conditions towards oxygen evolution reaction electrocatalysis. Pure phases of iron oxide were obtained, ferrihydrite and maghemite showed overpotentials of 460 and 480 mV at a current density of 10 mA cm–2, respectively. After calcination, hematite was formed and the overpotential was raised to 610 and 810 m V, respectively. The lower overpotential of the amorphous materials could be related to the lower electron transfer resistance and faster reaction rate. On the other hand, the calcinated materials presented higher specific activity, stability and higher Faradaic efficiency.
ISSN:	1678-4790
DOI:	10.21577/0103-5053.20240101