Electrolysis A Controlled and Reproducible Way to Create Surface Nanobubbles

4 Electrolysis A Controlled and Reproducible Way to Create Surface Nanobubbles 

A well-known method to produce gas at solid-liquid interfaces is through electrolysis. What happens here at the nanoscale Yang et al could monitor the growth of gaseous surface nanobubbles in real time using AFM, when the sample surface acted as of the hydrogen-producing electrode. A typical result of that experiment, at 1V, is shown in Fig. 7.17. 

Although the bubble grew in time, after some tens of seconds a stable situation set in and the bubble maintained a constant shape. This observation was reproduced by a further experiment, in which Yang et al measured the electrical current as a function 

Brenner and Lohse suggested that such a dynamic equilibrium may also stabilize standard nanobubbles. On the one hand the Laplace pressure 2afRc creates an overpressure in the bubble, which leads to a gas outflux. On the other hand, a gas influx, similar to that in the electrolysis experiments, could compensate for the outflux. It is known from experiments, but also from molecular dynamics simulations, that hydrophobic surfaces attract gas molecules. Brenner and Lohse suggested that these accumulated gas molecules are able to enter the nanobubble at the contact 

In summary, this overview article discussed two types of micro-and nanoscopic surface bubbles. The first type—gas entrapped in controlled surface defects—serves as nucleation sites in cavitation experiments. For these bubbles cavitation inception and the result- 

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