A composite including: at least one selected from a silicon oxide of the formula SiO.sub.2 and a silicon oxide of the formula SiO.sub.x wherein 0<x<2; and graphene, wherein the silicon oxide is disposed in a graphene matrix.

A cathode structure for cold field electron emission and method of fabricating a single-tip cathode structure for cold field electron emission. The cathode structure comprises a pointed cathode wire; and a graphene-based coating on at least a tip of the pointed cathode wire. In a preferred embodiment, graphene is coated on nickel tips by chemical vapour deposition wherein nickel functions as a catalyst for growth of graphene. The cathode structure provides stable cold field emission for electron microscopy and lithography applications and exhibits an ultralow work function value of about 1.1 eV.

A cathode structure for cold field electron emission and method of fabricating a single-tip cathode structure for cold field electron emission. The cathode structure comprises a pointed cathode wire; and a graphene-based coating on at least a tip of the pointed cathode wire. In a preferred embodiment, graphene is coated on nickel tips by chemical vapour deposition wherein nickel functions as a catalyst for growth of graphene. The cathode structure provides stable cold field emission for electron microscopy and lithography applications and exhibits an ultralow work function value of about 1.1 eV.

A field-emission type electron source includes (i) a single-crystal tungsten rod having a sharpened terminus and (ii) a mass of ZrO formed only on a portion of the surface, or the entire surface, of the sharpened terminus. In preferred design, the single-crystal tungsten rod is placed in a gaseous medium that consists of oxygen and a non-oxygen gas. The molar ratio between oxygen and the non-oxygen gas is greater than 1:1.

A composite including: at least one selected from a silicon oxide of the formula SiO.sub.2 and a silicon oxide of the formula SiO.sub.x wherein 0<x<2; and graphene, wherein the silicon oxide is disposed in a graphene matrix.

A composite including: at least one selected from a silicon oxide of the formula SiO.sub.2 and a silicon oxide of the formula SiO.sub.x wherein 0<x<2; and graphene, wherein the silicon oxide is disposed in a graphene matrix.

A composite including: at least one selected from a silicon oxide of the formula SiO.sub.2 and a silicon oxide of the formula SiO.sub.x wherein 0<x<2; and graphene, wherein the silicon oxide is disposed in a graphene matrix.

A composite including: at least one selected from a silicon oxide of the formula SiO.sub.2 and a silicon oxide of the formula SiO.sub.x wherein 0<x<2; and graphene, wherein the silicon oxide is disposed in a graphene matrix.

A composite including: at least one selected from a silicon oxide of the formula SiO.sub.2 and a silicon oxide of the formula SiO.sub.x wherein 0<x<2; and graphene, wherein the silicon oxide is disposed in a graphene matrix.

A composite including: at least one selected from a silicon oxide of the formula SiO.sub.2 and a silicon oxide of the formula SiO.sub.x wherein 0<x<2; and graphene, wherein the silicon oxide is disposed in a graphene matrix.