The thermal Marangoni effect during photoelectrochemical conversion

Abstract

Marangoni effect is a convective effect produced by surface tension gradient and has an important influence on the efficiency of hydrogen production by photoelectrochemical conversion. In this paper, COMSOL Multiphysics was used for numerical simulation to build a Marangoni effect model at the bubble interface in the photoelectrochemical conversion process, to clarify the mechanism of Marangoni effect of bubbles on the surface of photoelectrodes, and to discuss the influence of Marangoni effect on the process of bubble growth and separation. The results show that the thermal effect of light will cause the Marangoni convection around the bubbles and form a negative pressure zone at the root of the bubbles, which will attract the surrounding bubbles. Gravity has little effect on Marangoni convection, and an increase in the intensity of incoming light enhances the Marangoni effect. At the same time, Marangoni convection leads to a Marangoni force on the surface of the bubble, which prevents the bubble from leaving the surface of the photoelectrode.