Interfacial engineering via inserting functionalized water-soluble fullerene derivative interlayers for enhancing the performance of perovskite solar cells†
For n–i–p type perovskite solar cells (Pero-SCs), one of the limitations which hinder the improvement of device performance is the extremely low electrical conductivity of the TiO2 electron transport layer (ETL). Herein, two novel functionalized water-soluble fullerene derivatives C60O∼18(OH)∼10(NH2)∼8 (f-C60) and C70O∼18(OH)∼10(NH2)∼10 (f-C70) were prepared and utilized as buffer layers between ITO and a vacuum-deposited fullerene C60 ETL in Pero-SCs. After inserting f-C60 and f-C70 layers, the Pero-SCs showed an enhanced crystallinity of the perovskite film, more efficient charge transport, reduced recombination and a decreased charge-transport resistance. Therefore, a summit power conversion efficiency (PCE) of 16.97% was achieved for the device with the f-C60/C60 ETL, which was ∼24% higher than that of the control device (13.71%). The PCE of the Pero-SC based on the f-C70/C60 ETL also exhibited a 16% enhancement. This work demonstrated the great potential of f-C60 and f-C70 for application as ETLs in Pero-SCs.
- This article is part of the themed collection: 2018 Journal of Materials Chemistry A HOT Papers