Progress in the industrialization and in the understanding the fundamental properties of nanobubbles has historically been inhibited by ease of contamination and a lack of reproducibility. Here we show a method to nucleate nanobubbles using only the most basic of conditions - cold water at 4 °C deposited on heated highly oriented pyrolytic graphite (HOPG) substrates. This method thus avoids the need, as in previous studies, to use secondary liquids, salts or electrolysis to nucleate the nanobubbles, providing a pure system to study nanobubbles. The nanobubbles generated with this method are observed to survive for at least five days, barely changing their contact angles or heights after the first few hours. The stability of the nanobubbles in our system are discussed within the framework of some recently published theories.
An, Hongjie, Beng Hau Tan, Qingyun Zeng, Claus-Dieter Ohl