Laplace Pressure of Individual H2Nanobubbles from Pressure-Addition Electrochemistry.
The Young-Laplace equation is central to the thermodynamic description of liquids with highly curved interfaces, e.g., nanoscale droplets and their inverse, nanoscale bubbles. The equation relates the pressure difference across an interface to its surface tension and radius of curvature, but the validity in using the macroscopic surface tension for describing curved interfaces with radii smaller than tens of nanometers has been questioned. Here we present electrochemical measurement of Laplace pressures within single H2bubbles between 7 and 200 nm radius (corresponding, respectively, to between 200 and 7 atm). Our results demonstrate a linear relationship between a bubble's Laplace pressure and its reciprocal radius, verifying the classical thermodynamic description of H2nanobubbles as small as ∼10 nm.
Department of Chemistry, University of Utah , 315 S 1400 E, Salt Lake City, Utah 84112, United States.
Sean R
SR
German
Department of Chemistry, University of Utah , 315 S 1400 E, Salt Lake City, Utah 84112, United States.
Martin A
MA
Edwards
Department of Chemistry, University of Utah , 315 S 1400 E, Salt Lake City, Utah 84112, United States.
Qianjin
Q
Chen
Department of Chemistry, University of Utah , 315 S 1400 E, Salt Lake City, Utah 84112, United States.
Henry S
HS
White