Getter activation and use

A method for removing a contaminant from an environment comprising the steps of:

• (i) heating a reduced and passivated getter material containing crystallites of a metal comprising nickel, cobalt, or copper in elemental form encapsulated by a layer comprising an oxide of the metal and dispersed over the surface of a support to a temperature in the range (TT−X) to (TT+Y), where Tris the Tammann temperature of the metal in elemental form in degrees Centigrade, X is 400 and Y is 200, to form an activated getter material having a surface active for contaminant removal and a reduced metal surface area in the range of 5 to 50 m2/g and (ii) exposing the activated getter material to the environment containing the contaminant.