MOCHI (Mesoporous Optically Clear Heat Insulator) is a transparent, nanoporous material developed by University of Colorado Boulder physicists that traps heat while remaining see-through. With about 90% air by volume and a precisely controlled pore structure, MOCHI blocks heat transfer by interrupting molecular collisions. The material could cut window-related heat loss — about 30% of a home's losses — and help reduce building energy demand. Researchers also see potential for thermal harvesting and retrofit glazing applications, though scale-up and durability studies remain.
MOCHI: The Transparent Insulator That Could Dramatically Cut Window Heat Loss
large windows in a living room corner - Tom Merton/Getty Images
MOCHI — short for Mesoporous Optically Clear Heat Insulator — is a new transparent material developed by physicists at the University of Colorado Boulder that traps heat while remaining see-through. Combining unusually high air content with a precisely engineered pore structure, MOCHI aims to reduce window heat loss without sacrificing views.
What Is MOCHI?
"Mesoporous" describes a network of nanoscale, intermediate-sized pores. These pores increase surface area and allow the material to hold air — and because still air is a poor conductor of heat, most high-performance insulators rely on trapped air to block thermal transfer. In MOCHI's final form, air occupies roughly 90% of the material's volume, while the remaining solid matrix is arranged to preserve optical clarity.
How It Works
Heat travels as molecules collide and pass energy to each other. In a mesoporous structure, the solid pore walls interrupt those molecular collisions, suppressing heat transfer. As Ivan Smalyukh, senior author of the study, explains:
"The molecules don't have a chance to collide freely with each other and exchange energy."
MOCHI differs from conventional aerogels and other porous insulators because its pore size and organization are controlled precisely to avoid the scattering that makes many aerogels look cloudy. The team forms a molecular scaffold that is later replaced by air, producing a nearly transparent, air-rich solid.
a cozy home interior with a window seat - brizmaker/Shutterstock
Why It Matters
According to the U.S. Department of Energy, windows account for about 30% of a typical home's heat loss. Buildings consume roughly 40% of global energy, so reducing window-related losses can have a meaningful effect on energy bills and emissions. A transparent insulator like MOCHI could be used in window glazing, skylights, transparent walls, and retrofit films — lowering heating and cooling loads while preserving daylight and views.
Beyond Passive Insulation
The researchers also suggest MOCHI could play a role in thermal harvesting. Because it traps diffuse solar heat even on partly cloudy days, the material could be integrated with systems that channel collected thermal energy to heat water or interior spaces, expanding its potential from a passive glazing component to an active element in building energy systems.
Limitations and Next Steps
MOCHI is an experimental material and practical deployment will depend on factors such as manufacturing scale, durability, cost, and how it performs in full window assemblies (including frame and edge details). Future work will need to address these engineering challenges and confirm long-term performance under real-world conditions.
Researchers hope MOCHI will offer a practical path to clearer, more energy-efficient glazing that helps reduce building energy use without sacrificing daylight or view.
