Singh, RahulRahulSinghPraneeth, N. V.S.N. V.S.PraneethBiswas, SubarnaSubarnaBiswasPalabathuni, ManojManojPalabathuniMuralidharan, AnanduAnanduMuralidharanMishra, NimaiNimaiMishraKhatua, SaumyakantiSaumyakantiKhatua2025-08-312025-08-312024-10-2410.1002/adom.2024011322-s2.0-85205043646https://d8.irins.org/handle/IITG2025/28695Recently, giant quantum dots (g-QDs) with a core/interface graded alloy shell/shell structure have shown promise in reducing photoluminescence (PL) intermittency and improving photostability. However, this approach has been mainly demonstrated with red and green emitting g-QDs but the blue-emitting graded alloy QDs has remained less explored. To tackle this challenge, a composition gradient method is employed to create three blue-emitting CdZnS/Cd<inf>x</inf>Zn<inf>1–x</inf>S/ZnS core/interface graded alloy shell/shell (C/A/S) quantum dots (QDs) with different diameters. The sample with the largest diameter (gQD-3) exhibits superior optical characteristics, with a photoluminescence quantum yield (PLQY) of approximately 62% and around 80% ON/radiative events at the single-particle level. Conversely, the smallest diameter (gQD-1) sample shows lower PLQY and only 30% radiative events with longer OFF/nonradiative events. Probability distribution analysis of PL trajectories, fitted with a truncated power law, reveals a significantly higher carrier de-trapping rate in gQD-3 compared to gQD-1, attributed to its proximity to band edge trap states. Additionally, the largest diameter sample retains remarkable optical performance during 48 h of continuous UV irradiation in colloidal suspension and single-particle levels. These findings show optimized core/shell structures, gradual alloy interfaces, and outer shell coatings can stabilize blue-emitting quantum dots, advancing next-gen optoelectronics.falseblue-emitting giant-quantum dots | fluorescence intermittency | photostability | temperature stabilityArticle2195107124 October 202412401132arJournal1WOS:001320205600001