The photocatalytic hydrogen evolution experiments were performed in 9 mL gastight vials with 3 mL 20 µg mL -1 Pdots suspension. A 1.2 M ascorbic acid solution was prepared separately and modified to pH 4 with 3M NaOH. The Pdot suspension and ascorbic acid solution were degassed separately with argon gas, finally, 0.6 mL of the ascorbic acid was added to the Pdot suspension vial to a total of 3.6 mL. The vials were then illuminated with a LED PAR38 lamp (17 W, 5000 K, Zenaro Lighting GmbH, λ > 420 nm) used as the light source, in a black box removing any stray light. The light intensity on the illuminated area of the vial is 50 mW cm -2 , which is measured and then calibrated with a power sensor (Thorlabs S120C, Si, 400 -1100 nm, 50 mW connected to a PM100D console). The hydrogen was measured with a Gas chromatograph (PerkinElmer LLC, MA) calibrated from pure hydrogen injections. The H 2 was sampled by removing 100 µL gas from the headspace of the vial with a gas-tight Hamilton needle. Air was kept out of the vials by covering needle pinholes in the septum with Play-Doh clay (Hasbro, Inc) as the needles were retracted.