Cyanide Vacancy Effects on the Faradaic Efficiency of Water Oxidation by Prussian Blue Analog Catalysts

• Grant number: 25/20601-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2025
• End date: October 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Juliano Alves Bonacin
• Grantee: Nishta Nishta
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 24/09666-6 - Study of the formation of cyanide vacancies to increase the catalytic activity of Prussian blue analogues in water oxidation reactions, AP.R

Abstract

In the search for a more sustainable world, hydrogen emerges as an importantalternative and a symbol of an ecological future. However, its environmental benefits are intrinsicallylinked to the way it is produced. Currently, about 95% of the H¿ comes from fossil sources, and only5% of global hydrogen can be considered "clean," as it is obtained through low-carbon-emissionmethods. This is due to the fact that the cost of clean H¿ produced through water electrolysis isconsiderably higher than conventional methods that use fossil fuels, since the reaction requires catalyststo ensure efficient production of H¿ and O¿. Thus, the major challenge is related to the development ofaccessible and abundant catalysts with excellent catalytic activity, good conductivity, performance,stability, high efficiency in H¿ and O¿ production, and low cost. In this context, Prussian Blue (PB)-based catalysts stand out, especially under mild conditions such as neutral pH, due to their low cost andcomposition of abundant metals. However, the main challenge lies in the low concentration of activesites for catalysis, and defect engineering in these materials can contribute to enhance their catalyticactivity. With this in mind, the objective of this proposal is to study the Faradaic efficiency during theoxygen evolution reaction under mild pH conditions (pH = 7) of Prussian Blue analog (PBA)-basedcatalysts and to understand the influence of cyanide vacancies in these materials. For this purpose, PBanalogs with cyanide defects will be electrochemically synthesized, and O¿ evolution measurementswill be carried out using a Clark-type dissolved oxygen sensor. This approach ensures reliablemeasurements and comparison of the Faradaic efficiency between these materials. In addition to theseefforts, we also seek scientific and technological advancements, as well as excellence in the academictraining of the student Nishta Nishta. (AU)