Steel as a clean energy source: additive manufacturing of electrocatalysts for green hydrogen production and CO2 reduction

• Grant number: 25/04646-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: July 01, 2025
• End date: June 30, 2027
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Kahl Dick Zilnyk
• Grantee: Leonardo Shoji Aota
• Host Institution: Divisão de Engenharia Mecânica (IEM). Instituto Tecnológico de Aeronáutica (ITA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil
• Associated research grant: 20/06984-6 - Development of the additive manufacturing production chain of metal components, AP.NPOP

Abstract

Hydrogen is a promising renewable fuel to replace fossil fuels and thus mitigate the effects of ongoing climate changes, since it produces only water as product after its oxidation; however, it has a high cost due to the water electrolysis process used for its production. In addition, in order to reach a net zero CO2 emission given the currently employed technologies, it is necessary to remove CO2 from the atmosphere, ideally by generating a high value-added product via the electrochemical reduction of CO2. However, electrocatalysts used in both reactions are usually produced by complex and expensive synthesis routes that are difficult to scale up. In this project, we propose the use of a material that is widely used in industry, the ultra-high mechanical strength 15-5 PH stainless steel, and a well-established additive manufacturing technique, laser powder bed fusion. Gyroid and stochastic structures will be produced in order to generate a high surface area to improve the performance of green hydrogen production and CO2 reduction, while simultaneously providing a high mechanical strength-to-weight ratio. The process parameters and subsequent heat treatment will be adjusted to offer a range of microstructures by subjecting the material to controlled oxidation in gaseous or aqueous media. The strategy consists of using the alloying elements present in the matrix or in precipitates to form active centers for electrocatalysis, such as CuOx and NiOHx for hydrolysis and CO2 reduction, optimizing the performance and stability of the electrocatalyst. With the success of this project, we aim to produce low-cost electrocatalysts that are easily scalable and can also provide a structural function.