Highly energetic phenomena in water electrolysis

作者：Postnikov A V; Uvarov I V; Lokhanin M V; Svetovoy V B^*

来源：Scientific Reports, 2016, 6(1): 39381.

DOI：10.1038/srep39381

Water electrolysis performed in microsystems with a fast change of voltage polarity produces optically invisible nanobubbles containing H-2 and O-2 gases. In this form the gases are able to the reverse reaction of water formation. Here we report extreme phenomena observed in a millimeter-sized open system. Under a frequency of driving pulses above 100 kHz the process is accompanied by clicking sounds repeated every 50 ms or so. Fast video reveals that synchronously with the click a bubble is growing between the electrodes which reaches a size of 300 mu m in 50 mu s. Detailed dynamics of the system is monitored by means of a vibrometer by observing a piece of silicon floating above the electrodes. The energy of a single event is estimated as 0.3 mu J and a significant part of this energy is transformed into mechanical work moving the piece. The observations are explained by the combustion of hydrogen and oxygen mixture in the initial bubble with a diameter of about 40 mu m. Unusual combustion mechanism supporting spontaneous ignition at room temperature is responsible for the process. The observed effect demonstrates a principal possibility to build a microscopic internal combustion engine.

• 出版日期2016-12-16