Natural Chlorophyll Derivative Assisted Defect Passivation and Hole Extraction for MAPbI3 Perovskite Solar Cells with Efficiency Exceeding 20%

A chlorophyll derivative, sodium copper chlorophyllin (NaCu-Chl), is utilized to passivate the defects at the perovskite film surface via a solution post-treatment method. It is found that NaCu-Chl not only suppresses the defect-induced nonradiative recombination but also improves the film morphology. Moreover, NaCu-Chl treatment also facilitates efficient hole extraction from perovskite to Spiro-OMeTAD. As a result, NaCu-Chl-treated MAPbI(3) PSCs produce an optimal power conversion efficiency (PCE) of 20.27% with better ambient and thermal stability. This work offers an insight into the application of natural products and derivatives for fabrication of PSCs.

Automated summary

A solution post-treatment method using a chlorophyll derivative, sodium copper chlorophyllin (NaCu-Chl), is employed to passivate the defects on the surface of perovskite films. The treatment effectively suppresses nonradiative recombination and improves film morphology, resulting in perovskite solar cells with enhanced power conversion efficiency and stability. This study provides insights into the application of natural products and derivatives for the fabrication of perovskite solar cells.