Method for producing copper-selenide nanoparticles, aggregated bodies of copper-selenide nanoparticles, copper-selenide nanoparticles, and film-coated structure

A method for producing copper-selenide nanoparticles by flow process, the method comprising:

• forming a flowable copper precursor by combining a copper starting material and a ligand;
• forming a flowable selenium precursor by suspending a selenium starting material in a liquid;
• forming a flowable copper-selenium mixture by combining the flowable copper precursor and the flowable selenium precursor, the flowable copper-selenium mixture including a lower-polarity solvent;
• forming a segmented flow of the flowable copper-selenium mixture by appending a segment of an immiscible, non-reacting fluid to each of a series of fixed-length segments of the flowable copper-selenium mixture;
• forming a solution containing copper-selenide nanoparticles by conducting the segmented flow of the flowable copper-selenium mixture through at least one heating unit;
• and
• isolating the nanoparticles of copper selenide in an oxygen-depleted environment, including combining the solution containing copper-selenide nanoparticles and a deoxygenated, higher-polarity solvent to precipitate the nanoparticles of copper selenide, the higher-polarity solvent being more polar than the lower-polarity solvent.