Periodic Reporting for period 1 - MetGel (Bifunctional Metal Aerogels for Unitized Regenerative Fuel Cells)
Période du rapport: 2022-09-01 au 2024-08-31
The utilization of affordable and sustainable sources of energy has been a major worldwide concern, which has led to the implementation of several renewable energy systems in many developed countries. However, such systems are not enough to face the energy demand, and more advanced technologies are required. In this context, the use of hydrogen is postulated as an indispensable alternative to face the European energy demand. Hydrogen can be obtained by splitting water in an electrolyzer and then be transformed into electricity in a fuel cell. The combination of these two devices to implement a unique technology known as a Unitized Regenerative Fuel Cell (URFC) may transform the global energy production systems.
In a URFC, the transformation of hydrogen into energy takes place through catalyzed electrochemical reactions. The most efficient electrocatalyst to date is based on noble metals, which are costly and scarce and may assume up to 50% of the total cost of a cell. Thus, replacing noble metals with materials with lower cost, broader availability, and efficient electroactivity is crucial to implementing a real hydrogen economy. Therefore, the main objective of the MetGel project is to develop new, innovative, and low-cost bifunctional electrocatalysts able to replace commercial electrocatalysts based on noble metals
In a URFC, the transformation of hydrogen into energy takes place through catalyzed electrochemical reactions. The most efficient electrocatalyst to date is based on noble metals, which are costly and scarce and may assume up to 50% of the total cost of a cell. Thus, replacing noble metals with materials with lower cost, broader availability, and efficient electroactivity is crucial to implementing a real hydrogen economy. Therefore, the main objective of the MetGel project is to develop new, innovative, and low-cost bifunctional electrocatalysts able to replace commercial electrocatalysts based on noble metals
One of the main activities within MetGel project involves the development of a new methodology to synthesize transition metal aerogels (TMA) via microwave heating. Different synthesis conditions (time, temperature, volume, ratio between reagents and drying processes) were evaluated. TMA and bimetallic TMA based on different metals such as iron, nickel, manganese, and cobalt were successfully synthesized using chloride salts as the metallic precursor, and a mixture of sodium carbonate and glyoxylic acid as reducing solution.
MetGel project involves the first methodology developed to synthesize TMA by microwave heating using sustainable precursors. The final structure and morphology of the TMA were physiochemically characterized, and it was found that, besides the chemical composition, the porosity and morphology of the nanostructures can be modulated by modifying the synthesis conditions, evolving from microporous to macroporous materials and from flake to spherical shape. Some of these properties result in materials with excellent electroactivity towards the main electrochemical reactions that take place in a URFC, demonstrating their potential as candidates to replace current electrocatalysts based on noble metals.