Amino Acids for Perovskite Light-Emitting Diodes: Conformations, Mechanisms, and Applications

Among the most auspicious and efficient surface ligand candidates or additives to raise the efficiency of perovskite light-emitting diodes (PeLEDs) are amino acids (AAs), possessing a combination of amino group and carboxylic group. The AA molecules exhibit significant promise for coherent tailoring their molecular conformations to yield remarkable advantages and multi-functional properties. This raises a question that how PeLED devices can benefit greatly from the small amount of AA molecules integrated in perovskite films. In order to set up a structure-property relationship, the mysteries of the extraordinary improvement in performance of PeLEDs through AAs modification are disclosed. Furthermore, there is a critical discussion of workable guidelines for exploring AAs with optimal molecular conformations. Moreover, recent developments in blue, green, and red PeLED devices incorporating AAs are also highlighted in detail. Lastly, suggestions for future directions in research as well as the logical construction of functional AA molecules for potent and more stable PeLED devices are presented.