Making Hydrogen from CeO2? Just Use a microwave for Quick Results

Fossil fuels harm our climate. As we know, the world is inclining fast towards renewable, sustainable, green energy sources. In this search for climate-friendly fuels, Hydrogen has emerged as a potential source of decarbonization.

Technology has made it possible to produce hydrogen with zero or very little greenhouse gas emissions. The interest in Hydrogen is so high that the United States Department of Energy has set national goals to increase annual ‘clean hydrogen’ production from nearly zero to 10 million metric tons by 2030 and to 50 million metric tons by 2050. 

However, there is a critical bottleneck to the process. Traditional thermoelectric methods, ones that are dependent on the oxidation-reduction of metal oxides, require extremely high-temperature operations. The temperature may go as high as 1500 degrees centigrades. 

Recently, a team of researchers from POSTECH, Pohang University of Science and Technology, Korea, has worked out a way to bypass this bottleneck.

The process involves a familiar yet underutilized energy source: “microwave” energy. Yes! You’re not mistaken. It is the same source used in household microwave ovens. The research is titled ‘Thermodynamic Assessment of Gd-doped CeO2 for microwave-assisted thermochemical reduction.¹‘ 

In the following segment, we discuss the implications of this research. 

A Groundbreaking Technology Addressing Key Limitations in Clean Hydrogen Production Using Microwaves

The team consisted of interdisciplinary researchers working at POTECH and was led by Professor Gunsu S. Yun. It included doctoral candidate Jaemin Yoo (Department of Physics, Division of Advanced Nuclear Engineering), Professor Hyungyu Jin, and doctoral candidate Dongkyu Lee (Department of Mechanical Engineering). Recognized as a breakthrough in the pursuit of sustainable energy, the research was featured on the Inside Front Cover of the Journal of Materials Chemistry A.

The researchers started with the premise that while microwaves could heat food efficiently, they could drive chemical reactions as well. They introduced this notion to lowering the reduction temperature of Gd-doped ceria (CeO2). Gd-doped ceria (CeO2) is a benchmark material for hydrogen production, and microwave energy could reduce the reduction temperature of this material by over 60 percent – to below 600 degrees centigrades. 

Microwave energy could replace 75 percent of the thermal energy needed for the reaction. The finding is justifiably a breakthrough for sustainable hydrogen production.

While explaining why the research and its findings could be considered revolutionary, Professor Hyungyu Jin had the following to say:

“This research has the potential to revolutionize the commercial viability of thermochemical hydrogen production technologies. It will also pave the way for the development of new materials optimized for microwave-driven chemical processes.”

Professor Gunsu Yun termed the introduction of this new mechanism and its overcoming of the existing process limitations as ‘major achievements’ that could only be made possible through the close interdisciplinary collaboration of the research team. 

Another breakthrough achieved by the team could be found in creating Oxygen Vacancies. These are material structure defects that help split water into hydrogen. While traditional methods might take hours at very high temperatures, the POSTECH team showed how the same results could be achieved in just minutes at temperatures below 600°C by leveraging microwave technology.

While the POSTECH research offered a significant breakthrough, there are many other research organizations worldwide that have been active in producing innovative methods for clean hydrogen production. One of the organizations to be at the forefront of such research is the National Renewable Energy Laboratory, a national laboratory of the United States Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy LLC.

Click here to learn about the breakthrough that made hydrogen more attractive as an energy source.

Low-Cost Hydrogen Production: Other Efforts

Developed in collaboration with Xcel Energy, NREL’s wind-to-hydrogen (Wind2H2) demonstration project links wind turbines and photovoltaic (PV) arrays to electrolyzer stacks, which pass the generated electricity through water to split it into hydrogen and oxygen. The project is currently active at the National Wind Technology Center near Boulder, Colorado. The overarching aim of the project is to improve the system efficiency of producing hydrogen from renewable resources in quantities large enough and at costs low enough to compete with traditional energy sources such as coal, oil, and natural gas.

Another way of producing clean hydrogen is using sunlight to directly split water into hydrogen and oxygen. The photovoltaic industry has already developed sophisticated multijunction cell technologies for photoelectrochemical (PEC) light-harvesting systems that generate sufficient voltage to split water and are stable in a water/electrolyte environment.  The NREL has its PEC system that it has developed.

The NREL system can generate hydrogen from sunlight without the cost and complexity of electrolyzers, achieving a solar-to-hydrogen conversion efficiency of 12.4% (lower heating value) using captured light. Further research at NREL is focused on developing more efficient, lower-cost materials and systems that are durable and resistant to corrosion in aqueous environments.

Click here to learn what makes hydrogen the future of fuel.

Biological Hydrogen 

Another exciting path that NREL has been exploring deals with ‘Biological Hydrogen.’ NREL scientists are developing pretreatment technologies to convert lignocellulosic biomass into sugar-rich feedstocks that can be directly fermented to produce hydrogen, ethanol, and high-value chemicals.

Additionally, efforts are also underway to identify a consortium of Clostridium that can directly ferment hemicellulose to hydrogen.

Other research areas in the domain of Biological Hydrogen involves the following:

• Bio-prospecting efficient cellulolytic microbes, such as Clostridium thermocellum, can ferment crystalline cellulose directly into hydrogen to lower feedstock costs.
• Identification of a model cellulolytic bacterium.
• Exploring the potential of the model cellulolytic bacterium for genetic manipulations, including sensitivity to antibiotics and ease of genetic transformation.
• Developing strategies to generate mutants that are blocked selectively from producing waste acids and solvents to maximize hydrogen yield.

While organizations, research institutes, and labs are active worldwide, private companies are active as well. 

1. Linde (LIN +1.14%)

One of the companies to be at the forefront of clean hydrogen production for years now is Linde. The company claims that its innovative technologies, including the efficient compression and safe refueling of hydrogen, coupled with decades of experience, make its infrastructure unrivaled. 

The company’s operations, which are aimed at clean hydrogen production, involve several methods and strategies. Electrolysis for green hydrogen production, for instance, involves electrolyzers powered with renewable energy.

In electrolysis, water is split into hydrogen and oxygen using electricity generated entirely from renewable energy sources. This process takes place inside units called electrolyzers. While electrolyzers vary in size, capacity, and technology, the fundamental chemistry remains the same.

Currently, there are two main electrolysis technologies: alkaline and PEM (Proton Exchange Membrane)—both of which, according to Linde, can produce high-purity hydrogen on-site and on demand.

 Alkaline electrolysis uses two electrodes separated by a porous diaphragm and a liquid alkaline solution as the electrolyte. The electrolyte solution allows hydroxide ions to be transported between the electrodes to form oxygen and hydrogen, but they are not consumed during the reaction. The technology could be reliable yet cost-efficient.

On the other hand, PEM electrolysis uses pure water and a solid polymer electrolyte instead of a liquid solution to allow electricity to split the water into hydrogen and oxygen. Hydrogen protons pass through the membrane, combining with electrons to form H2 gas on the cathode side.

Linde is also into offering effective Carbon Capture for Use and Storage (CCUS) technologies for a range of strategies. It has innovative delivery solutions in place for injecting Hydrogen into existing natural gas pipelines to serve a wide variety of end-point applications. 

Linde runs highly advanced storage operations for hydrogen, which is stored in underground salt caves. Apart from being an experienced partner in the development of energy parks, Linde has been operating the first commercial high-purity Hydrogen cavern for over a decade. It also has decades of experience in constructing Hydrogen liquefaction systems to produce liquid hydrogen for ease of storage and transportation. 

According to the latest available financial data, Linde registered sales worth US$8.356 billion for the quarter ended September 30, 2024. 

2. Air Products (APD -0.56%)

Another company that contributes significantly to the clean hydrogen production space is Air Products. The company believes that clean hydrogen production from renewable energy sources will be essential to decarbonizing hard-to-electrify industrial processes like steelmaking and chemical processing.

The company has already committed US$15 billion to projects that will advance low-carbon hydrogen production and speed up the energy transition. 

The company’s clean hydrogen applications include hydrogen fueling for automobiles, buses, forklifts, ships, trains, and trucks. Road transportation accounts for nearly 12% of global emissions. Converting diesel buses to zero-emission hydrogen fuel cell buses can reduce global greenhouse gas emissions and improve air quality. Air Products is a leader in Hydrogen bus fueling and is involved in projects around the world. 

NEOM Green Hydrogen Company (NGHC), an equal production joint venture of ACWA Power, Air Products, and NEOM, is setting up the world’s largest green-hydrogen-based ammonia production facility to run on renewable energy. This plant will produce up to 600 tonnes per day of carbon-free hydrogen in the form of green ammonia as a cost-effective solution for transportation and industrial sectors globally.

Air Products’ new net-zero hydrogen energy complex is set to make Edmonton, Alberta, the center of western Canada’s hydrogen economy. While Construction is well underway in Edmonton at Air Products’ transformative new hydrogen facility, connecting this facility to the company’s existing pipeline network will help its refining and petrochemical customers reduce the carbon intensity of their energy products and improve their sustainability performance. Moreover, the best-in-class liquefaction facility will help to accelerate the use of hydrogen as an emission-free transportation fuel across western Canada. 

Air Products’ Louisiana Clean Energy Complex will produce low-carbon hydrogen to power mobility and industrial markets in the Gulf Coast region and beyond. The facility is estimated to capture and sequester 95% of its carbon dioxide emissions (over 5 million tons per year), permanently sequestering the CO2 in ideal geological pore space in Louisiana. 

This project is the largest US investment by Air Products, built with the intention to help the state of Louisiana reduce its  GHG emissions to net zero by 2050. 

Air Products also plans to invest approximately $500 million to build, own, and operate a 35-metric-ton-per-day facility to produce green liquid hydrogen at a greenfield site in Massena, New York, along with setting up liquid hydrogen distribution and dispensing operations. The project will result in the avoidance of 6 million tonnes of CO2 over the project’s lifetime. The project will use hydroelectric power from the St. Lawrence River to fuel the production of carbon-free liquid hydrogen.

For the fiscal year that ended on September 30, 2024, the company had registered a sales figure of over US$12 billion. 

Into the Future With Clean Hydrogen

There is enough encouragement for companies and research organizations to keep developing newer ways for reliable and cost-effective hydrogen production. The US Department of Energy, for instance, selected as many as seven winners in 2023 for its collective US$7 billion funding allocated by the Bipartisan Infrastructure Law to get a series of “hydrogen hubs” up and running. To qualify, each hub had to convincingly demonstrate that it could ​”produce at least 50–100 metric tons of clean hydrogen per day and reduce greenhouse gas emissions.”

The most active participants named in the DOE’s chosen hydrogen hubs included the likes of AES Corporation (AESC +1.07%), Air Liquide, Amazon (AMZN -2.2%), Bloom Energy (BE -10.61%), Chevron (CVX -1.87%), ExxonMobil (XOM -3.63%), GTI Energy, Holtec, Mitsubishi Power Americas, Plug Power (PLUG -7.14%), and (TRP +0.79%). 

Cutting-edge technologies can also be involved in advancing the production and distribution of hydrogen. The NREL, for instance, performs accelerated testing and cycling of 700 bar hydrogen dispensing hoses at the Energy Systems Integration Facility using automated robotics to simulate field conditions. Here, the robots mimic the repetitive stress of a person bending and twisting a hose to dispense hydrogen into a fuel cell vehicle’s onboard storage tank. Researchers look into mechanical, thermal, and pressure stress efficiencies of new and used hydrogen dispensing hoses.

Hydrogen is having a moment, and the momentum can only grow from here. According to organizations that track the global buildout of hydrogen projects, 680 large-scale hydrogen production projects were announced in 2022 alone, resulting in $240B worth of direct invREL is also into regularly performing systems-level analyses on a variety of sustainable hydrogen production and delivery pathways so that it could help determine status improvements resulting from technology advancements, cost as a function of production volume, and the potential for cost reductions.

There is no doubt that Hydrogeestment through 2030, while private equity and venture firms invested record amounts in hydrogen companies at different stages of development in 2022, offering $3.1B in private equity to hydrogen-related companies and $2.6B in venture capital investment across 192 startups in the space.

While speaking about the significance of this momentum, Adria Wilson, a director on Breakthrough Energy’s US Policy & Advocacy team, said Recent policy wins mean that affordable, clean hydrogen will be a decarbonization tool we have at our disposal in the next decade, if not sooner.

However, while being thoroughly optimistic, one must also remember that there is still a long way to go. According to numbers provided by the World Resources Institute, 95% of hydrogen is made from fossil fuels, typically via a process known as steam methane reforming (SMR), in which water is heated at high temperatures to produce steam that reacts with natural gas and produces hydrogen and carbon dioxide (CO2). The process remains significantly GHG emitting, releasing as much as 10 kilograms of CO2 equivalent per kilogram of hydrogen (kg CO2e/kg H2) to 14 kg CO2e/kg H2, an amount similar to the carbon emissions from producing and burning a gallon of gasoline.

Clean hydrogen production methods would have to help us get rid of such methods. The transition would have to be fast yet through sustainable methods.

Click here for a list of top clean energy stocks with sustainability focus.