Clean air through nanotechnology

Founded in 2015, 4C Air is devoted to bringing clean air through innovative nanomaterials. Using technology developed at Stanford University, we are developing products and solutions for the most hazardous air pollutants, PM2.5. We have products developed for personal and home use and are actively exploring filtration for automotive, HVAC, clean room, and medical uses.

Our Team

World-class scientists

Steven Chu


Professor of Physics and Molecular Biology, Stanford University

Professor Steven Chu known for his research regarding the cooling and trapping of atoms with laser light, for which he won the Nobel Prize in Physics in 1997. Afterwards, he served as the 12th United States Secretary of Energy from 2009 to 2013, where he was a vocal advocate for renewable energy and environmental research. Returning to Stanford, his group has focused on biophysics, energy, and environmental technology. He is a member of the U.S. National Academy of Sciences, the American Academy of Arts and Sciences, the American Philosophical Society, the Academia Sinica, and is a foreign member of the Chinese Academy of Sciences and the Korean Academy of Science and Engineering.

Yi Cui


Professor of Materials Science and Engineering, Stanford University

Professor Yi Cui is a world-leading expert in nanotechnology, materials science, energy and environmental technology. He is a highly proliferate scientist/engineer/inventor with more than 360 research publications and more than 50 patent applications. At the age of 28, he was awarded Innovators under 35 by MIT Technology Review, and he has consistently been awarded “The World’s Most Influential Scientific Minds” by Thomson Reuters. He is a Co-Director of the Bay Area Photovoltaic Consortium and a Co-Director of the Battery 500 Consortium funded by the US Department of Energy. He is a Fellow of Materials Research Society and the Fellow of Royal Society of Chemistry.

Meng Sui