Electro spinning under sub critical voltage

A simple method was proposed to reduce the critical voltage of electrospinning and gain finer nanofiber. Beside the collector, a ground inducing plate was introduced into the electrospinning experiment setup, and the distance between spinneret and inducing plate can be adjusted. Under the same applied voltage, the electrical field strength around the spinneret increase as the distance between spinneret and inducing plate decreases. When inducing plate moved nearly to the spinneret (the distance is about 1.5~2cm), a charged jet would be leaded out from the Taylor cone due to the higher electrical field strength. An interesting phenomenon was found that electrospinning keep on running, when inducing plate moved away. Therefore, with the help of inducing plate, electrospinning can run under the applied voltage that smaller than critical voltage required in the conventional electrospinning. Bending instability of charged jet would be weaken by the lower applied, and finer nanofiber can be gained by this method. The diameter of nanofiber increase from 141um to 162nm, when the subcritical voltage increasing from 3.75kV to 4.5kV. This method would improve the precise position deposition and diameter controlling of nanofiber.