Thermodynamic stability of interfacial gaseous states.
We studied the thermodynamic stability of interfacial gaseous states on atomically smooth highly ordered pyrolytic graphite (HOPG) in water using atomic force microscopy. Quasi-two-dimensional gas layers (micropancakes) required a higher supersaturation of gas than spherical-cap-shaped nanobubbles. The two forms of gas coexisted at a sufficiently high supersaturation of gas where one or more of the nanobubbles may sit on top of a micropancake. The micropancakes spontaneously coalesced with each other over time. After the coalescence of two neighboring micropancakes which each had had a nanobubble on top, one nanobubble grew at the expense of the other. We analyzed these results assuming temporal and local quasi-equilibrium conditions.
Zhang
Xue Hua
XH
Maeda
Nobuo
N
Hu
Jun
J
D005740:Gases / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry; D018625:Microscopy, Atomic Force; D011758:Pyrroles / Q000737:chemistry; D013816:Thermodynamics
D005740:Gases; D011758:Pyrroles; D006108:Graphite