Published: Aug. 15, 2024 By

The Smalyukh group holding a plaque in front of the labThe Soft Matter Physics Smalyukh Research Group holding the Guinness World Record plaque.

Only a few individuals or teams are awarded by the Guinness Book of World Records for specific actions or research they鈥檝e done. One of those teams is led by the 精品SM在线影片 Professor of Physics Ivan Smalyukh, who, with his research group, developed 鈥渢he World鈥檚 Most Transparent Material.鈥

This material鈥攁 synthetic gel-derived material known as aerogel鈥攊s around 97-99% transparent, compared to glass, which is around 92% transparent. While many aerogels are being manufactured worldwide, the aerogel Smalyukh and his team have created involves fibers of cellulose, a protein derived from plants. Their aerogel, which has now been successfully patented, can be added to windows to boost thermal insulation, increasing the overall efficiency of a building.

What is an Aerogel?

Aerogels are often described as 鈥渇rozen smoke鈥 or 鈥渟olid air鈥 because they are incredibly light and porous. They are made by removing the liquid from a gel, leaving behind a mostly empty solid network.

鈥淭here are different ways people define aerogels, but it鈥檚 roughly one percent solid by volume and 99 percent air, so it鈥檚 mostly air,鈥 explained Smalyukh.

Despite being extremely lightweight, aerogels are excellent thermal insulators, which means they can prevent heat from passing through them. This makes them useful in everything from space exploration to insulating homes.

鈥淚n the U.S., unfortunately, we still have almost 50 percent of single-pane windows,鈥 added Smalyukh. 鈥淲hat that means is that you heat the building, especially during winter, but then a lot of that energy is actually lost through the windows.鈥

By retrofitting these windows with aerogel, the thermal efficiency of these windows can be increased as more heat is trapped inside.

The Challenge with Transparency

Traditional aerogels, however, despite being effective insulators, have drawbacks鈥攖hey tend to scatter light, making them appear cloudy or opaque. This limits their use in applications where transparency is important, such as windows.

鈥淭hey are so hazy because you have many tiny particles that are somehow connected to each other in a network. And the length of the pores between these particles ranges from a few nanometers to micrometers.鈥

That鈥檚 where the new aerogel Smalyukh and his team developed, called SiCellA, comes in. Instead of having various pore lengths and particle sizes like other aerogels, the researchers meticulously controlled the size of the particles, the cellulose fibers, within SiCellA, along with the distance between these particles.

鈥淭he cellulose fibers we use are typically under 6 nanometers in diameter. Because the particles themselves have a diameter much smaller than the wavelengths of light and the pores in between them are also much smaller, therefore, the scattering of light is very small.鈥

This produces a higher transparency percentage of the aerogel, allowing it to let through 97-99% of visible light while scattering and reflecting only 1% of the remaining light.

Boosting Energy Efficiency

Thermal image of window panes

Infrared thermal imaging photos of different types of treated and untreated window panes mounted into an insulated box. These boxes are designed to hold extreme hot and cold temperatures to test the thermal insulating properties of each window type. The double-paned Insulated Glass Unit (IGU) containing the SiCellA aerogel (Top Left) and the single window pane treated with the SiCellA aerogel film (Bottom Left) show markedly higher thermal insulation properties than a conventional double-paned IGU (Top Right), and a single pane of glass (Bottom Right).

To create comfortable indoor environments, buildings consume around 40% of the energy produced worldwide. Windows and skylights are often the weakest points in a building鈥檚 insulation, allowing heat to escape in the winter and letting it in during the summer.

鈥淚f we only could stop that heat loss, then we would not need to generate this much energy,鈥 Smalyukh elaborated. 鈥淭hat means shutting down some coal-based power plants or using less fossil fuels.鈥

By using this SiCellA in windows, buildings could become much more energy-efficient, reducing the need for heating and cooling and lowering energy bills. Because SiCellA is so transparent, it can be used in windows without blocking the natural light that makes spaces bright and inviting. This means that homes and offices can stay comfortable all year round while using less energy, contributing to a more sustainable future.

A Guinness World Record

The incredible transparency of SiCellA hasn鈥檛 gone unnoticed. The Guinness Book of World Records has officially recognized it as the most transparent material ever created.

When Smalyukh & team presented their results at an ARPA-E project meeting, the program manager suggested submitting SiCellA to the Guinness Book of World Records to help disseminate the project's outcomes. While Smalyukh and his team did submit the record to Guinness back in 2019, the public release of this World Record wasn鈥檛 until much later, as the team was patenting SiCellA at the same time and had to wait for the patents and in to be accepted before breaking the news.

鈥淚t was interesting and exciting to see the record entry in the Guinness Book of World Records,鈥 Smalyukh added. 鈥淲e were happy that everything went through.鈥

Title Image: Senior Research Associates Vladyslav Cherpak and Bohdan Senyuk hold听SiCellA aerogel film, suspended in plastic wrap, in front of the foothills. Image courtesy of the Smalyukh Group