Evaluating the performance of a single-layer blue light-emitting electrochemical cell based on a perovskite-polymer composite

Abstract

Most of the planar light-emitting devices have a multilayer structure that consists of electron-transporting (ETL), hole- transporting (HTL), and emissive (EL) layers. Usually, the manufacturing of the devices with a complex architecture is related to the employment of expensive materials and high-tech processes such as vacuum deposition. Therefore, cost-effective and large- scale wet chemical production of efficient single-layer light-emitting devices remains a hot topic in the field of optoelectronics. Although finding a suitable semiconducting material for the engineering of such devices is challenging, inorganic cesium lead halide perovskites have recently emerged as promising candidates for this purpose. In contrast to many conventional AIII BV and AII BVI semiconductors, these perovskites exhibit roomerature excitonic emission with high quantum yield and spectral linewidth of 14-30?nm. All of these features are required for the design of the devices demonstrating efficient light output and high color purity. So far single-layer perovskite light-emitting devices have been shown in the form of a light-emitting electrochemical cell (pero-LEC) giving bright green electroluminescence. In the meanwhile, this study has to be extended to blue and red pero-LECs to construct RGB pixels in the next-generation displays. Herein, we present the engineering of a blue pero-LEC based on inorganic perovskite-polymer composite which operates within the electrochemical doping model. We analyze the device performance to derive its crucial physical parameters and suggest a way towards its efficient and long-term operation.