TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: In the composition, the copper-containing chalcogenide is selected from copper sulfide (Cu2S), CuS, copper selenide (Cu2Se), CuSe, copper tin sulfide (Cu2SnS3), Cu4SnS4, and copper tin selenide (Cu2SnSe3). The tin-containing chalcogenide is selected from SnS2, SnS, SnSe, SnSe2, Cu2SnS3, Cu4SnS4, and Cu2SnSe3. The zinc-containing chalcogenide is ZnS or ZnSe. The composition further comprises an additive up to 1 wt.%, based on the total weight of the composition, where the additive is a sodium salt, elemental sulfur or elemental selenium.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The coated copper-containing chalcogenide nanoparticles comprise an organic stabilizing agent selected from alkyl amines, alkyl thiols, trialkylphosphine oxide, trialkylphosphines, alkylphosphonic acids, polyvinylpyrrolidone, polycarboxylates, polyphosphates, polyamines, pyridine, alkylpyridines, peptides comprising cysteine and/or histidine residues, ethanolamines, citrates, thioglycolic acid, oleic acid, and polyethylene glycol. The coated tin-containing chalcogenide nanoparticles comprise an organic stabilizing agent selected from alkyl amines, alkyl thiols, trialkylphosphine oxide, trialkylphosphines, alkylphosphonic acids, polyvinylpyrrolidone, polycarboxylates, polyphosphates, polyamines, pyridine, alkylpyridines, peptides comprising cysteine and/or histidine residues, ethanolamines, citrates, thioglycolic acid, oleic acid, and polyethylene glycol. The coated zinc-containing chalcogenide nanoparticles comprise a an organic stabilizing agent selected from alkyl amines, alkyl thiols, trialkylphosphine oxide, trialkylphosphines, alkylphosphonic acids, polyvinylpyrrolidone, polycarboxylates, polyphosphates, polyamines, pyridine, alkylpyridines, peptides comprising cysteine and/or histidine residues, ethanolamines, citrates, thioglycolic acid, oleic acid, and polyethylene glycol. The fluid medium is selected from toluene, chloroform, dichloromethane, pyridine, hexane, heptane, octane, acetone, 2-butanone, methyl ethyl ketone, water, and alcohol. Preferred Process: Alternatively, the process comprises depositing a dispersion onto a substrate, where the dispersion comprises: (a) a fluid medium; (b) coated copper-containing chalcogenide nanoparticles; (c) coated tin-containing chalcogenide nanoparticles; and (d) coated zinc-containing chalcogenide nanoparticles, where the chalcogenide is a sulfide or selenide and the molar ratio of Cu:Zn:Sn:(S+Se) of the composition is about 2:1:1:4. The substrate is selected from glass, metal, or polymer substrates; molybdenum-coated soda lime glass; molybdenum-coated polyimide films; and molybdenum-coated polyimide films further comprising a layer of a sodium compound. The process further comprises removing the fluid medium to form a coated substrate. The chalcogenide is a sulfide and the process further comprises heating the coated substrate to form a CZTS film on the substrate. The chalcogenide is a selenide and the process further comprises heating the coated substrate to form a CZTSe film on the substrate. The chalcogenide is a mixture of a sulfide and a selenide and the process further comprises heating the coated substrate to form a CZTS/Se film on the substrate.