A process for the post-deposition treatment of colloidal quantum dot films to improve photodetector performance. A colloidal quantum dot film is first deposited on a suitable substrate or device structure, given a ligand exchange, and then allowed to dry into a completed film. Next, a solution is prepared consisting of dilute H2O2 mixed with a polar solvent such as isopropyl alcohol solution. The prepared film and substrate are then immersed into the prepared solution over a set interval of time. After which, the film is removed and rinsed with solvent, then dried with clean N2 gas. After this treatment, the colloidal quantum dot film is ready for use as a photodetector.