1. (a) Device structure diagram of tandem PeLED; (b) Diagram of carrier transport and luminescence principle in tandem PeLEDs; (c-e) UV-visible absorption and photoluminescence characterization of tri-color perovskites: (c) Quasi-2D blue perovskite films; (d) Green perovskite QDs; (e) Red perovskite QDs

2. Schematic diagram of energy levels of blue/green tandem PeLED and carrier transport process

3. (a, d, g) Electroluminescence spectra, (b, e, h) intensity mappings, and (c, f, i) comparison of blue/green tandem PeLEDs with different NPB thicknesses under different driving voltages

4. EL performance of blue/green tandem PeLEDs

5. Electroluminescence spectra of red/green/blue tandem PeLEDs

S1. EL performance of red, green, and blue monochrome PeLEDs

S2. EL spectra of red, green, and blue monochrome PeLEDs under an applied voltage of 4.0 V