Encapsulated Passivation of Perovskite Quantum Dot (CsPbBr3) Using a Hot-Melt Adhesive (EVA-TPR) for Enhanced Optical Stability and Efficiency

Abstract

The notable photophysical characteristics of perovskite quantum dots (PQDs) (CsPbBr3) are suitable for optoelectronic devices. However, the performance of PQDs is unstable because of their surface defects. One way to address the instability is to passivate PQDs using different organic (polymers, oligomers, and dendrimers) or inorganic (ZnS, PbS) materials. In this study, we performed steady-state spectroscopic investigations to measure the photoluminescence (PL), absorption (A), transmission (T), and reflectance (R) of perovskite quantum dots (CsPbBr3) and ethylene vinyl acetate/terpene phenol (1%) (EVA-TPR (1%), or EVA) copolymer/perovskite composites in thin films with a thickness of 352 ± 5 nm. EVA is highly transparent because of its large band gap; furthermore, it is inexpensive and easy to process. However, the compatibility between PQDs and EVA should be established; therefore, a series of analyses was performed to compute parameters, such as the band gap, the coefficients of absorbance and extinction, the index of refractivity, and the dielectric constant (real and imaginary parts), from the data obtained from the above investigation. Finally, the optical conductivities of the films were studied. All these analyses showed that the EVA/PQDs were more efficient and stable both physically and optically. Hence, EVA/PQDs could become copolymer/perovskite active materials suitable for optoelectronic devices, such as solar cells and perovskite/polymer light-emitting diodes (PPLEDs).

Large-scale preparation of CsPbBr3 perovskite quantum dot/EVA composite adhesive film by melting for crystal silicon solar cell

“…As the loading of masterbatch in the melting composite adhesive film decrease from 1:15 to 1:35, the intensity of the corresponding emission peaks increase and then decrease, and the champion one achieves at the ratio of 1:25. In fact, once the content of the masterbatch reaches a certain ratio, the polymer chain of EVA could not effectively prevent the agglomeration of PQDs [40], which will lead to large crystal size of the QDs and PL spectra redshift, and the transmittance will also decrease. Therefore, the best ratio of masterbatch and excipient in the melting composite adhesive film is 1:25, under which the melting fast radiation recombination [41].…”

Copolymer Mediated Engineering of Halide Perovskites and Associated Devices: Current State and Future

“…Recently, QDs were conjugated with ethylene vinyl acetate/terpene phenol (1%) (EVA‐TPR (1%), or EVA) to form copolymer/perovskite composite thin films. [ 52 ] The thin films were tested by steady‐state spectroscopic investigations. The reason for choosing EVA was due to its low cost and high band gap which provided transparency.…”