The present invention provides a method of coating an electrospray emitter
with silver and then gold utilizing wet-coating processes. First, the
electrospray emitter is immersed in a silver-containing liquid solution
to coat the electrospray emitter in a layer of silver. Next, the
silver-coated electrospray emitter is removed from the silver solution
and rinsed with water. The silver-coated electrospray emitter is then
annealed to stabilize the silver layer. Once the silver layer has been
stabilized, the silver-coated electrospray emitter is immersed into a
gold-containing liquid solution and a voltage is applied. This voltage
serves to electrochemically deposit a gold layer onto the silver layer.
The gold- and silver-coated electrospray emitter is then removed from the
gold-containing liquid solution and rinsed with water and, preferably,
with nitric acid.