Research progress and applications of electrokinetic paddleless pumps

The bladeless pump has garnered significant attention due to its advantages of low noise, no vibration, small size, and light weight. In particular, the micro bladeless pump is an important type of micro-electromechanical device, with significant application value in fields such as medicine, health, biology, and robotics. This paper first introduces the background of micro-electromechanical systems, and then discusses in detail the classification, principles, development history, and applications of electrostatic interface-driven bladeless pumps. Bladeless pumps are classified into continuous and discrete types based on the form of fluid flow. The continuous type is represented by electrohydrodynamic pumps, while the discrete type includes dielectric electrowetting pumps, photo-induced electrowetting pumps, optoelectronic coupling pumps, and electrostatic pumps. The working principles of these four types of pumps are elaborated, and their development histories are reviewed in detail, from the initial concept to their current widespread applications. In terms of applications, electrohydrodynamic pumps, with their simple structure and ease of integration with soft materials, are widely used in soft robots and wearable devices. Dielectric electrowetting pumps have significant applications in microchemical reactions, tunable liquid lenses, and heat dissipation. Photo-induced electrowetting pumps and optoelectronic coupling pumps, due to their low cost and compact structure, are suitable for home-based detection devices and cell manipulation. Electrostatic pumps, with their non-contact and precise control advantages, are widely used in biological and chemical fields. The paper concludes by discussing the current challenges and future directions of bladeless pump technology, pointing out that photo-induced electrowetting and optoelectronic coupling pumps have room for improvement in material selection and structural design, while electrostatic pumps need to address the efficiency issue under microgravity conditions. In the future, the applications of electrostatic interface-driven bladeless pumps are expected to continue to expand in the fields of medicine, health, biology, and robotics.