Researchers in Brazil have developed an advanced catalyst that significantly improves the efficiency and stability of ethanol-to-hydrogen conversion, offering a potential pathway to lower-cost, low-carbon hydrogen production, according to Agência Fapesp.
The study, led by Fabio Coral Fonseca of the Institute for Energy and Nuclear Research (Ipen) and published in the International Journal of Hydrogen Energy, demonstrates that fine control over the processing of perovskite-type ceramic materials can enhance hydrogen yields while eliminating the need for expensive noble metals.
Hydrogen is widely viewed as a key component of the global energy transition, particularly when produced from renewable sources. In Brazil, abundant ethanol derived from biomass presents a strategic opportunity for hydrogen generation through ethanol steam reforming (ESR), a high-temperature process in which ethanol reacts with steam to produce hydrogen and carbon dioxide.
The research focuses on improving catalysts used in ESR. Instead of applying nickel to the surface of ceramic materials through conventional impregnation methods, the team incorporated nickel directly into the perovskite crystal structure during synthesis. Under controlled conditions, the metal “exsolves,” forming highly stable nickel nanoparticles firmly anchored to the surface.
This approach enhances catalytic stability, reduces carbon deposition and prevents particle agglomeration at high temperatures, common issues that degrade conventional catalysts.
A key finding of the study is that calcination temperature plays a decisive role in performance. Catalysts calcined at 650°C delivered the best results, achieving 100% ethanol conversion, producing more than four moles of hydrogen per mole of ethanol, and maintaining stable operation for up to 85 hours with minimal coke formation. Higher calcination temperatures reduced surface area, limited nickel exsolution and weakened performance.
Fonseca emphasized that manufacturing conditions are as important as material composition. “A relatively simple adjustment in processing completely changes performance,” he noted.
Beyond ethanol reforming, the team is also exploring direct ethanol fuel cells as an alternative route for energy conversion. Their broader research into metallic exsolution in perovskites includes prior collaboration with U.S. institutions supported by the São Paulo Research Foundation and the National Science Foundation.
The scientists are now advancing toward highly controlled epitaxial thin films to study catalytic behavior at the atomic scale, using advanced characterization tools at Sirius, Brazil’s synchrotron light source.
By demonstrating that abundant, low-cost metals such as nickel can achieve high catalytic performance when properly engineered, the research outlines a promising route to reduce reliance on noble metals and strengthen sustainable hydrogen production, particularly in Brazil, where ethanol infrastructure is already well established.
