Recently, Haoxin Wang published a research article entitled "Electron transport interface engineering with pyridine functionalized perylene diimide-based material for inverted perovskite solar cell" in Chemical Engineering Journal (Chem. Eng. J. 2022, 438, 135410, DOI: 10.1016/j.cej.2022.135410). Jiangsu University is the first completed unit of the paper, Haoxin Wang is the first author, Prof. Cheng Chen and Prof. Ming Cheng are the corresponding authors.

Rational interfacial regulation engineering of electron transport layers (ETLs) is desirable to construct highly efficient inverted planar perovskite solar cells (p-i-n PSCs). In this work, a pyridine-functionalized perylenediimide electron transport material (ETM) named SFX-Py-PDI2 was developed and employed at the perovskite/ETL. Benefiting from high electron mobility, suitable energy alignment, and defect passivation effects, PSCs with SFX-Py-PDI2 as ETM achieved better performance than the reference device with PC₆₁BM, which is particularly evident in the improvement of open circuit voltage (V_oc). In view of this, SFX-Py-PDI2 was introduced into perovskite films via anti-solvent treatment to passivate the surface interface and grain boundary defects in perovskite, and the combined use of PC₆₁BM as ETL successfully further improved the efficiency of p-i-n PSCs to 21.3 %. In addition, the SFX-Py-PDI2-based devices exhibited good long-term stability in the unpackaged condition, maintaining over 80% of the initial efficiency after aging at 65 °C and 50-60% RH for 1000 h.

The research work is financed by the National Natural Science Foundation of China, Jiangsu Province "Innovation and Innovation Talents", Jiangsu Province "Six Talent Peaks" and other projects.