Ability to manipulate materials at the nano scale offers new prospects for strategic technology to overcome the climate crisis
The researchers at the Brazilian Center for Research in Energy and Materials (CNPEM) have celebrated numerous successes in the use of advanced microscopy and nanotechnology resources to investigate and modify materials that are viable for use in devices that utilize sunlight to break apart water molecules to obtain low-carbon hydrogen (also known as green hydrogen).
Photoelectrolysis prototype developed at CNPEM (CNPEM Outreach)
The researchers at the Brazilian Center for Research in Energy and Materials (CNPEM) have celebrated numerous successes in the use of advanced microscopy and nanotechnology resources to investigate and modify materials that are viable for use in devices that utilize sunlight to break apart water molecules to obtain low-carbon hydrogen (also known as green hydrogen).
“I have been working in this area for 20 years,” says Flávio Leandro Souza of the Brazilian Nanotechnology National Laboratory, “and I joke that nothing compares to the progress we’ve made over the past two years.”
The global race to find cleaner energy sources has become more urgent as the effects of climate change become more evident, showing how scientific resources are essential and strategic to overcome this challenge.
As a high-density energy source with flexible uses and zero local emissions, hydrogen has the potential to bring together notable advantages, with a major impact in various sectors. The most strategic of these are manufacturing (steel production), agricultural inputs (ammonia production), and energy for transport (aviation as well as land and sea shipping). However, most hydrogen is still produced from non-renewable sources, making significant contributions to greenhouse gas emissions.
Challenges in the photoelectrolysis of water
Photoelectrolysis, a method that uses only sunlight (and no other external energy sources) to break down water molecules to obtain hydrogen with only oxygen as a byproduct, is also often called “artificial photosynthesis.”
The main technical challenge in implementing this technology in processes to produce hydrogen is its low efficiency; only a low percentage of captured sunlight is actually absorbed by the system and used in the process of photoelectrochemical splitting of the water molecules (previously, around 3%). This poor efficiency translates into high costs for producing hydrogen. But new technology developed by CNPEM has the potential to significantly reduce greenhouse gas emissions.
H2SUS
CNPEM’s sustainable hydrogen program (H2SUS) has the ambitious goal of developing solutions for the low-carbon economy, such as boosting the level of this 100% Brazilian technology and developing new methods to manufacture more efficient electrodes. And some recent publications from this program with promising results have been highlighted in scientific journals.
Achievements
Recent articles in high-impact publications have described important advances in the fabrication of components that could be used in photoelectrolysis systems. Other studies have been conducted that validate methods that are currently being patented and address incorporating elements into the fabrication of large electrodes.
The results so far have been promising to continue developing processes in order to scale up an innovative technology in this field.
“In the past, some materials were modified and the results were observed. Today, the accumulated knowledge about the elements and the methods of incorporating them into materials allows us to project ahead of time in the lab what the characteristics of each element could contribute to the results we hope to obtain,” explains researcher Flávio Leandro Souza.
Results
The proof of concept to control capacities using iron oxide (hematite), an abundant and low-cost material, was featured on the cover of Sustainable Energy & Fuels. Incorporating gallium and hafnium ions and a combination of nickel, iron, and oxygen as modifiers led to a 65% increase in hydrogen/oxygen production compared to the pure material.
“The concentration of these modifying elements accounts for less than 4% of the total; in other words, 96% is iron oxide. This study adds a new methodology to the scenario which involves a simple device, low complexity for synthesis, versatility in the use of deposition techniques, and most importantly, controlled incorporation of multiple modifiers,” Souza adds.
In another article, published in Materials Today Energy, CNPEM researchers reveal the prospects for scaling up this technology through the ability to incorporate previously tested chemical routes to fabricate components that are already being used in photoelectrolysis prototypes.
“Manipulating the interfaces, eliminating defects, or even changing the chemical composition of these interfaces to encourage chemical reactions in such a way that can be scaled up and is economically viable are the essential requirements for fabricating high-efficiency materials, and we are on this path,” says Souza.
Scaling up in the laboratory
Research continues to investigate other aspects such as the durability and toxicity of materials used in the components of prototypes that can efficiently extract hydrogen from even seawater. CNPEM’s Engineering Division is already working to plan a laboratory with all the infrastructure needed to test on increasingly larger scales.
Video details assembly process and shows a photoelectrolysis prototype in action >
Sustainability Platform
CNPEM is also recognized for the Sustainability Platform developed by researchers at the Brazilian Biorenewables National Laboratory (LNBR), which can calculate the economic, social, and environmental impacts of various technologies. The platform, which already has an established database, has been extended to accommodate new technologies, which will allow it to expand assessments for hydrogen and compare the different production technologies and applications.
“Our goal is to guide decision-making throughout the process of research and development for new technologies, offering information based on sustainability criteria and regional aspects. Knowing Brazil’s differentials is essential for technological development, valuing our natural capital in the transition towards renewable manufacturing,” explains LNBR/CNPEM researcher Edvaldo Morais.
About CNPEM
A sophisticated and effervescent environment for research and development, unique in Brazil and present in few scientific centers in the world, the Brazilian Center for Research in Energy and Materials (CNPEM) is a private non-profit organization, under the supervision of the Ministry of Science, Technology and Innovation (MCTI). The Center operates four National Laboratories and is the birthplace of the most complex project in Brazilian science – Sirius – one of the most advanced synchrotron light sources in the world. CNPEM brings together highly specialized multi-thematic teams, globally competitive laboratory infrastructures open to the scientific community, strategic lines of investigation, innovative projects in partnership with the productive sector and training of researchers and students. The Center is an environment driven by the search for solutions with impact in the areas of Health, Energy and Renewable Materials, Agro-environment, and Quantum Technologies. As of 2022, with the support of the Ministry of Education (MEC), CNPEM expanded its activities with the opening of the Ilum School of Science. The interdisciplinary higher course in Science, Technology and Innovation adopts innovative proposals with the aim of offering excellent, free, full-time training with immersion in the CNPEM research environment. Through the CNPEM 360 Platform, it is possible to explore, in a virtual and immersive way, the main environments and activities of the Center, visit: https://pages.cnpem.br/cnpem360/.