UV-vis spectroscopy (absorption) measurement: UV-vis spectroscopy was performed on 50 mg/mL PbS films (encapsulated) using an Agilent Cary 6000i UV/vis/NIR machine in transmission mode. For solution-state measurements, a 1 cm path length quartz cuvette was used. The PbS QDs solution-state absorption was measured in hexanes with a baseline of the absorption of hexanes neat. We also used a second relative method to calculate the absorption values, which resulted in similar values (see SI for more information).