TECHNOLOGY FOCUS - ELECTRONICS - Preferred Device: The absorber layer includes copper, indium, selenium, sulfur or gallium. The transparent electrode includes a transparent conductive polymeric layer (preferably poly-3,4-ethylenedioxythiophene (PEDOT) doped with poly(styrenesulfonate) (PSS)) or a layer of zinc oxide.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: In (M1), obtaining the core nanoparticles includes forming the core nanoparticles using a technique from the group of evaporation-condensation, electroexplosion of wire, organometallic synthesis, metal salt reduction, and/or a combination of high temperature decomposition of a metal carbonyl precursor and the reduction of a metal salt in the presence of surfactants. The core nanoparticles includes chemical bath deposition, and/or electroless plating, and/or atomic layer deposition, and/or two-stage evaporation-condensation, and/or disproportionation of organometallic precursors, and/or decomposition of organometallic precursors, where coating the core nanoparticles includes electroless plating using an alkaline or acidic plating bath. (M1) further involves fluidizing the core nanoparticles during the atomic layer deposition. The fluidizing the core nanoparticles includes placing the nanoparticles on a stage and vibrating the stage at an ultrasonic frequency during the atomic layer deposition. In (M2), coating the nanoparticles includes coating a first portion of the core nanoparticles with gallium and/or indium and/or aluminum and a second portion of the nanoparticles with gallium and/or indium and/or aluminum; forming the ink, paste, or paint includes mixing the first and second portions together or at least one technique selected from contact printing, top feed reverse printing, bottom feed reverse printing, nozzle feed reverse printing, gravure printing, microgravure printing, reverse microgravure printing, comma direct printing, roller coating, slot die printing, meiyerbar coating, lip direct coating, dual lip direct coating, capillary coating, ink-jet printing, jet deposition and/or spray deposition. The core nanoparticles includes copper core nanoparticles coated with indium and copper core nanoparticles coated with gallium. The coated nanoparticles are mixed with other components to form an ink, paint or paste (preferably dispersants, binders and/or resins, emulsifiers, anti-foaming agents, defoaming agents, dryers, solvents, fillers, extenders, thickening agents, film conditioners, anti-oxidants, flow and leveling agents, plasticizers and/or preservatives). The core nanoparticles includes obtaining an organic nanoparticle having a diameter between 1 - 100 nm and coating the organic nanoparticle with at least one element of group IB and/or group IIIA.Preferred Components: The core nanoparticles contain copper and gallium. The layer of metal includes indium or gallium. The core nanoparticles are 0.1 - 500 (preferably 1 - 100, especially 10 - 50, particularly 1 - 10) nm in diameter.