Electrospray

The name electrospray is used for an apparatus that employs electricity to disperse a liquid or for the fine aerosol resulting from this process. High voltage is applied to a liquid supplied through an emitter (usually a glass or metallic capillary). Ideally the liquid reaching the emitter tip forms a Taylor cone, which emits a liquid jet through its apex. Varicose waves on the surface of the jet lead to the formation of small and highly charged liquid droplets, which are radially dispersed due to Coulomb repulsion.

In the late 16th century William Gilbert set out to describe the behaviour of magnetic and electrostatic phenomena. He observed that, in the presence of a charged piece of amber, a drop of water deformed into a cone. This effect is clearly related to electrosprays, even though Gilbert did not record any observation related to liquid dispersion under the effect of the electric field.

In 1750 the French clergyman and physicist Jean-Antoine (Abbé) Nollet noted water flowing from a vessel would aerosolize if the vessel was electrified and placed near electrical ground. He also noted that similarly "a person, electrified by connection to a high-voltage generator, would not bleed normally if he were to cut himself; blood would spray from the wound".

In 1882, Lord Rayleigh theoretically estimated the maximum amount of charge a liquid droplet could carry; this is now known as the "Rayleigh limit". His prediction that a droplet reaching this limit would throw out fine jets of liquid was confirmed experimentally more than 100 years later.

In 1914, John Zeleny published work on the behaviour of fluid droplets at the end of glass capillaries. This report presents experimental evidence for several electrospray operating regimes (dripping, burst, pulsating, and cone-jet). A few years later, Zeleny captured the first time-lapse images of the dynamic liquid meniscus.

Between 1964 and 1969 Sir Geoffrey Ingram Taylor produced the theoretical underpinning of electrospraying. Taylor modeled the shape of the cone formed by the fluid droplet under the effect of an electric field; this characteristic droplet shape is now known as the Taylor cone. He further worked with J. R. Melcher to develop the "leaky dielectric model" for conducting fluids.

...
Wikipedia