Abstract: A paste (32) for use in metallization of a solar cell (12) includes an organic vehicle (44) and a mixture of copper-containing particles (46), metal-oxide-containing nanoparticles (50), and secondary oxide particles (52) different from the metal-oxide-containing nanoparticles (50). The secondary oxide particles (52) include particles (42) of a metal oxide and a metal of the metal oxide capable of reducing at least some of the metal-oxide-containing nanoparticles (50) to metal when heated. The organic vehicle (44) is capable of reducing the metal oxide of the secondary oxide particles (52) upon decomposition of the organic vehicle (44). A paste (32) includes a mixture of particles (42) including metallic copper particles (46), nanoparticles (50), and metal oxide particles (52) in the organic vehicle (44). The nanoparticles (50) include at least one oxide of nickel, copper, cobalt, manganese, and lead.

Abstract: Copper inks are provided that include a plurality of core-shell nanostructures, with each nanostructure including a copper core and a barrier metal shell, a diameter of less than about 500 nm, and a distinct boundary between the copper core and the barrier metal shell. Methods of forming a copper ink are further provided and include an initial step of synthesizing an amount of copper nanoparticles in an aqueous solution. An amount of a barrier metal is then added to the copper nanoparticles to form a dispersion of the barrier metal and the copper nanoparticles, and a reducing agent is subsequently added to the dispersion to produce a copper ink comprising core-shell nanostructures having a copper core and a barrier metal shell. Copper films are then formed by applying that copper ink to a substrate and sintering the copper ink.

Abstract: The presently-disclosed subject matter includes methods for making a copper ink. In some embodiments the methods comprise forming an aqueous solution that includes copper and adding an amount of a surfactant to the aqueous solution to thereby produce a copper ink that includes a dispersion of copper nanoparticles. In some embodiments the methods further include adding an amount of a reducing agent to the aqueous solution. In some instances the copper inks are formed from copper salts, and in some embodiments the copper inks do not include oxides of copper. The presently-disclosed subject matter also includes copper inks formed by the presently-disclosed methods as well as methods of forming a copper film from a copper ink.

Abstract: Copper inks are provided that include a plurality of core-shell nanostructures, with each nanostructure including a copper core and a barrier metal shell, a diameter of less than about 500 nm, and a distinct boundary between the copper core and the barrier metal shell. Methods of forming a copper ink are further provided and include an initial step of synthesizing an amount of copper nanoparticles in an aqueous solution. An amount of a barrier metal is then added to the copper nanoparticles to form a dispersion of the barrier metal and the copper nanoparticles, and a reducing agent is subsequently added to the dispersion to produce a copper ink comprising core-shell nanostructures having a copper core and a barrier metal shell. Copper films are then formed by applying that copper ink to a substrate and sintering the copper ink.