Enhancement of photo-oxidation resistance of quantum dots by hindered phenol and its application in diffusion plate

Alloyed quantum dots (QDs) show great potential for photoluminescence (PL) applications. However, the oxidative decay of QDs during photoexcitation has been a major hurdle to the application of QDs. Blocking water-oxygen erosion by coating oxides on the surface of QDs is a common technique. Even though, this approach often leads to alterations in the optical properties of QDs and reduced compatibility with polymers. In this paper, hindered phenol was utilized to treat QDs to form QD/Hindered phenol complexes. Using the reduction of phenolic hydroxyl group in the hindered phenol, the hindered phenol was used as an exhausted substance to protect QDs from oxidation . After 450 h of aging, the obtained QD/Hindered phenol complex kept the photoluminescence quantum yield (PLQY) at 48 %. The luminance of the QD diffusion plate prepared by the QD/Hindered phenol complexes maintained above 98 % of the initial value after aging 1032 h. The introduction of phosphite ester further improved the photostability of QD/Hindered phenol complex under blue-light excitation. This technique promotes the application of QDs in polymers and offers a new reference for improving the stability of QDs under photoexcitation.