Photovoltaic charge lithography for droplet transport and electrowetting on passive dielectric substrates

Our results confirmed the effectiveness of photovoltaic charge lithography for manipulating droplets on diverse dielectric substrates. The method enabled complex functionalities, including light-exposure-tailored electrowetting, droplet transport of single and multiple consecutive droplets (even uphill), and controlled coalescence. Furthermore, the technique proved to be capable of printing surface charges on flexible polymeric substrates, demonstrating its broad applicability. Numerical simulations supported the experimental observations by offering valuable insights into the interactions between the printed charges and the droplets.