Innovations in exploiting photo-controlled Marangoni flows for soft matter actuations
Chalikkara Farzeena, Thamarasseril Vijayan Vinay, Bindhu Sunilkumar Lekshmi, Chetteente Meethal Ragisha, Subramanyan Namboodiri Varanakkottu
Abstract
along the liquid surface is sufficient to create a strong Marangoni flow. This can be done by either optically heating (thermocapillary) or modulating the chemical composition (soluto-capillary) at the liquid surface, which could be exploited to realize the transport/assembly of colloidal particles, droplets, bubbles and liquid marbles. In this perspective article, we focus on the innovative approaches in modulating surface tension using light, in the context of soft matter and microfluidic applications. First, we discuss the photo-controlled Marangoni flow-driven patterning and assembly of colloidal particles in different microfluidic systems, such as liquid droplets and liquid films. Next, we review the various methods in which the photo-controlled Marangoni flows are being exploited for the actuation of liquid droplets and liquid marbles over solid as well as soft substrates. Finally, we highlight the recent trends in optically controlled flow-based reconfigurable optics and energy harvesting systems.