When 17th-century Dutch scientist Anton van Leeuwenhoek fashioned the world’s first real microscope by polishing lenses and positioning them in a tube that produced magnifying power, he opened doors to a new world in which people could view objects as small as one millionth of a meter. At the time, van Leeuwenhoek couldn’t have known that 350 years later, his technology would become so advanced that scientists would be using it today to tackle some of the 21st-century’s greatest challenges.

Today, researchers at the National Energy Technology laboratory (NETL) use an array of microscopy tools to advance key energy research, particularly research related to fossil energy. Circe Verba, Ph.D., of the Lab’s Geology and Geospatial Analysis Team, offered insight into advanced microscopy.  

“Microscopes and imaging techniques have long been vital for researchers to observe structures and quantify composition,” she said. “NETL researchers use advanced microscopy and microanalysis techniques to tackle some of the challenges facing the safe and efficient use of our nation’s fossil energy resources.”

For example, Verba explained that researchers use microscopy to generate and analyze 2D and 3D digital images of rocks. They can then use these images to evaluate oil and gas resources at specific sites, giving them a better understanding of mineral distributions, geological formation properties (like pore space and organic content), and specific sites’ potential for carbon storage. The information is also useful for decision makers who need to determine the best approach for commercial extraction methods like enhanced oil recovery (EOR). EOR is a technique that injects carbon dioxide (CO₂) deep underground to force oil and gas to the surface.

Verba said microscopy images also help experts examine wellbore systems—the cement and steel casings inside of oil and gas wells—to measure the performance of materials and find potential defects. This work can help prevent leaks or blowouts by determining what type of cement works best to seal wellbores.

“We also use microscopy techniques and sophisticated instruments to quantify chemical and mineralogical constituents in coal by-products and coal-bearing strata,” Verba said. “That can lead to detection of rare earth elements in by-products like fly ash.”

Rare earth elements are a series of chemical elements in the earth’s crust that are vital to many modern technologies such as clean energy, electronics—including smartphones—transportation, health care, national defense, and other applications.

In addition, NETL researchers use an array of microscopy instruments and spectroscopy—the science of how light interacts with matter—to study the following:

• Catalysts—substances that increase the rate of chemical reactions
• New metals and alloys for use in the harsh environments of advanced, more efficient energy systems
• Pressing energy issues related to the capture and storage of CO₂
• The energy potential of methane hydrates—molecules of methane trapped inside ice that could be a major energy resource of the future.

According to Verba, NETL experts use a wide collection of tools in energy research that, though based on van Leeuwenhoek’s early efforts, are far more advanced than the first microscope.

Some of the microscopy devices that NETL uses in its energy research include the following:

• Scanning electron microscope (SEM) – An electron microscope that produces compositional or topological images of a sample by scanning it with a focused beam of electrons
• Electron microprobe (EMP) – An analytical tool used to non-destructively determine the precise chemical composition, including trace elements, of small volumes of solid materials
• A DualBeam Focused Ion Beam (FIB)-SEM – A system that operates like a SEM, but uses both an electron beam to image samples, and a focused beam of ions to remove surface material.

Verba said complex image processing and visualization techniques are required to assemble microscopy data into a format that is useful for scientific inquiry. At NETL, Verba’s team collaborates closely with academic and industry partners to incorporate additional software modules and materials that augment image acquisition and processing work.

Use of high-tech microscopy tools is just one way NETL works to discover, integrate, and mature technology solutions to enhance the nation’s energy foundation and protect the environment for future generations.