Triboelectric Programmed Droplet Manipulation for Plug-and-Play Assembly

Abstract

Programmed droplet transport which is typically directed by surface energy gradients or external fields, is crucial in domains ranging from chemical reaction modulation to self-powered intelligent sensing. However, droplet motion control remains constrained by path reconfiguration, requirements on chemical surface modification, and platform complexity. Here, a more universal plug-and-play droplet manipulation paradigm based on liquid-solid contact electrification and triboelectricwetting on common dielectric surfaces is reported. By regulating the electrical double layer via asymmetric ion dynamics, the triboelectric charge polarity of droplets can be adjusted, enabling in situ manipulation without path reconfiguration dictated by the conventional droplet motion output. Droplets achieved an ultrahigh velocity of 450 mm s⁻¹ on general surfaces, significantly exceeding the speeds observed in droplets subjected to constant electrostatic fields with chemical modifications. This flexible and modular functionally decoupled manipulation strategy offers an environmentally friendly, cost-effective, and versatile paradigm, facilitating applications in chemical analysis and smart sensing.