초록 |
Recently, the SnO2-based electron transport layer (ETL) has been widely used for high-efficiency planar lead-halide perovskite solar cells (PSCs). However, non-radiative decay of charge carrier at the ETL-Perovskite interface due to the poor film morphology has caused the performance reduction and efficiency deviation. Herein, a blend of water-soluble polymer PEIE and SnO2 nanoparticle is introduced as ETL to improve the film morphology. Polyelectrolyte PEIE (polyethyleneimine, ethoxylated) has been demonstrated as an interfacial material which is often used for decreasing energy barrier and suppress the trap-assisted recombination. PEIE promotes SnO2 nanoparticle to be uniformly dispersed in colloidal ink preventing aggregation. Therefore, pin-hole free and thinner films of ETL could be obtained which lead to enhancement in efficiency and reproducibility. Finally, the optimized PSCs exhibit a maximum PCE of 18.1% compared with the pristine device with PCE of 16.9%. |