Comprehensive study on electrospray deposition in the single Taylor cone–jet mode by changing the spatial electric potential using a ring-shaped ternary electrode

In this work, the effect of changing the spatial electric potential to the spray current and the threshold voltage in the single Taylor cone–jet mode of the electrospray deposition (ESD) process has been investigated. The spatial electric potential between a nozzle electrode and a counter electrode was deformed by using an additional ring-shaped ternary electrode. The voltage ranges of the stable single Taylor cone–jet were determined from the current–voltage (I–V) characteristics of the system. Depending on the changes occurring in the spatial electric potential around the nozzle electrode, a shift of the threshold voltage to form a stable single Taylor cone–jet was clearly observed. For further investigation, the spatial electric potential and electric-field lines were analyzed by numerical simulations based on the computational finite element method. The deformation of the electric-field lines between the nozzle and counter electrodes implies a lack of droplet adhesion onto the ternary ring electrode and a focus of electrospray. Finally, we demonstrated the ESD of polymer materials with an area of 371 ± 160 mm2 at a deposition rate of 314 ± 73 nm/min. The ESD technique is an important additive surface-modification method that is applicable to a variety of materials and suitable for highly viscous solutions and fragile biological samples.