Abstract: Light-driven flow reactors are configured with an aerosol delivery apparatus that is designed to improve the reactive process with respect to forming uniform product compositions at higher rates. In particular, the reactant delivery system can deliver an aerosol having an average droplet size of no more than about 50 microns, and in some embodiments 20 microns, and with less than 1 droplet in 10,000 having a diameter greater than 5 times the average droplet size. In some embodiments, the edge of the aerosol generator can be placed within about 6 centimeters of the edge of the light beam passing through the reaction chamber. The average aerosol velocity can be no more than about 5 meters per second. In some embodiments, the aerosol generator can comprise a non-circular opening and a gas permeable structure that is used to generate a mist that is delivered from the apparatus as an aerosol.