Abstract: A system for creating targeted vanadium oxide (VO2) nanoparticle compositions comprising a stock reaction mixture that is a fluid combination of at least one vanadium source combined with at least one dopant source. Each dopant source contains at least one target dopant element. The ratio of the number of vanadium atoms in the vanadium source to the number of target dopant element atoms in the dopant source is less than or equal to 10:1. A solvent that is compatible with said stock reaction mixture is selected. A pressure regulator increases the pressure of the solvent and the stock reaction mixture to between 0 and 5,000 psi. A heating element increases the temperature of the solvent to between 50 and 500° C. A mixing unit receives and mixes a continuous flow of stock reaction mixture with solvent to heat the stock reaction mixture and initiate formation of the targeted vanadium oxide (VO2) nanoparticle composition.