Can Light Make Water Evaporate Without Heat?
from The Deep Dive Lab: Unraveling Materials Science Hosted by Son Hoang
What if light could make water evaporate without heating it? A controversial idea called the photomolecular effect proposed that visible photons might directly help water molecules escape from the air-water interface. But when researchers put pure water to the test, the result was strikingly different. 🔬💧 In this episode, we explore a 2026 PNAS study that measured evaporation directly while illuminating neat water with blue, green, and red light. The researchers also used heterodyne-detected vibrational sum-frequency generation (HD-SFG) to examine hydrogen bonding and molecular orientation at the water surface. Then they pushed the test even further with femtosecond laser pulses whose peak intensities were more than ten orders of magnitude higher. The result? No detectable change in evaporation or interfacial structure. What does this tell us about the photomolecular effect—and about the difference between pure water and complex light-absorbing materials? ⚛️🌊 #WaterEvaporation #PhotomolecularEffect #Physics #Chemistry #LaserScience #SurfaceScience #TheDeepDiveLab
Embed this episode
No transcript yet.