Researchers conducted investigations to realize highly stable films of CsPbX3 quantum dots (QDs) capped with a halide ion pair dimethyl ammonium bromide (DDAB)), a relatively short ligand that facilitated carrier transport in the QD film and enabled the researchers to fabricate efficient perovskite LEDs (PeLEDs). The synthesis of these films was only possible through the design of a ligand-exchange strategy that included an intermediate step to desorb protonated OAm, which would result in the degradation of all-inorganic perovskite QDs (APQDs) through a direct conventional ligand-exchange route.