Improved performance of inverted green perovskite light-emitting diodes with dicarboxylic acid additive

Metal halide perovskites (MHPs) have attracted extensive interest as semiconductor materials, offering a high absorption coefficient, excellent carrier mobility and minimal defect density ^[1-3]. However, defect states at the surface and grain boundaries act as non-radiative recombination centers, substantially hindering charge transport and decreasing device efficiency and stability ^[4]. This study presents a dicarboxylic acid passivation molecule—adipic acid (AAC) integrated into FAPbBr₃ perovskite. The interactions between the carboxyl groups (-COOH) on either side and under-coordinated Pb²⁺ sites facilitate crystal growth while passivating perovskite defects, yielding high-quality films. As a direct outcome of this, the fabricated inverted green PeLED achieved a peak external quantum efficiency (EQE) of 11.96%.