Ag-CsPbBr3 quantum dots/PMMA composite film for tunable white light emitting diodes

• Ag-CsPbBr 3 CPQDs with strong PL emission intensity and high PLQY. • Ag-CsPbBr 3 CPQDs/PMMA film with long-term stability. • Tunable WLEDs from cold to warm light. We demonstrated a colloidal perovskite Ag-CsPbBr 3 quantum dots /PMMA (Ag-CsPbBr 3 CPQDs/PMMA) composite film. Compared to the traditional CsPbBr 3 CPQDs, the Ag-CsPbBr 3 CPQDs exhibits two advantages: i) enhanced photoluminescence (PL) emission intensity approaching 40%; ii) up to 94% of photoluminescence quantum yield (PLQY). More importantly, the polymethylmethacrylate (PMMA) film makes the Ag-CsPbBr 3 CPQDs/PMMA film still have a 56% of PLQY and high PL emission intensity at a storage time of 5 months. And through changing the ratio of CsPbI 3 CPQDs in the Ag-CsPbBr 3 CPQDs, the Ag-CsPbBr 3 CPQDs/PMMA film can easily tune the correlated color temperature (CCT) from cold to warm light.