Optimized Dual-Layer Architecture for Spectral Management and Charge Dynamics in PEDOT:PSS/Si Hybrid Solar Cells

Poly(3,4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) hybrid heterojunction solar systems on silicon (Si) substrates have attracted substantial interest in the scientific community due to their projected high efficiency, as well as a simpler and more cost-effective production process. However, one notable disadvantage of PEDOT:PSS/Si PV is its low open circuit voltage. To overcome this limitation, our study suggests a novel approach for depositing PEDOT:PSS thin films in two layers. We employ PH1000 (EG 7wt%) with a thickness of above 90 nm and PH1000 (DMSO 5wt%) with a thickness of ≥ 60 nm. This fabrication approach involves precisely controlling the deposition of PEDOT:PSS layers to alter interfacial properties, resulting in better charge carrier transport and extraction at the PEDOT:PSS/Si interface. The modified PEDOT:PSS interface resulted in a significant increase in open circuit voltage (Voc). This rise indicates better charge extraction and lower recombination losses. Specifically, the device with a 150 nm PEDOT:PSS thin film has a much higher open circuit voltage of 600.47 mV without any further changes. Furthermore, it has a fill factor of 0.60 and a high-power conversion efficiency of 5.31%. The findings from the enhanced dual-layer deposition technique highlight the need of specialized engineering approaches in increasing device performance. This study sheds light on the successful utilization of PEDOT:PSS hole transport layer(s) to increase Voc in PEDOT:PSS/Si heterojunction solar cells, emphasizing the need of precise interface engineering approaches in advancing HHSC technology.