Force Spectroscopy Revealed a High-Gas-Density State near the Graphite Substrate inside Surface Nanobubbles

• DOI: 10.1021/acs.langmuir.8b03383
• Publication Date: 2019-01-15T21:06:11Z
• Authors: Shuo Wang; Limin Zhou; Xingya Wang; Chunlei Wang; Yaming Dong; Yi Zhang; Yongxiang Gao; Lijuan Zhang; Jun Hu
• Keywords: Force Spectroscopy; Pyrolytic carbon; Surface forces apparatus

The absorption of gas molecules at hydrophobic surfaces may have a special state and play an important role in many processes interfacial physics, which has been rarely considered previous theory. In this paper, force spectroscopic experiments were performed by nanosized AFM probe penetrated into individual surface nanobubbles contacted with highly ordered pyrolytic graphite (HOPG) substrate. results showed that the adhesion gas/solid interface was much smaller than air measured same probe. data further analyzed van der Waals theory, result implied density near substrate inside about 3 orders magnitude higher under standard pressure temperature (STP). Our MD simulation indicated layers exhibited high-density nanobubbles. This provide new insight understanding abnormal stability contact angle on surfaces, significant impact their applications.