Inkjet-Printed Organic Solar Cells and Perovskite Solar Cells: Progress,Challenges, and Prospect

In recent years,the power conversion efficiency of organic solar cells(OSCs)and perovskite(PVSCs)has increased to over 19%and25%,respectively.Meanwhile,the long-term stability of OSCs and PVSCs was also significantly improved with a better understanding of the degradation mechanism and the improvement of materials,morphology,and interface stability.As both the efficiency and lifetime of solar cells are approaching the commercialization limit,fabrication methods for large-area OSCs and PVSCs that can be directly transferred from lab to fab become essential to promote the industrialization of OSCs and PVSCs.Compared with the coating methods,inkjet printing is a mature industrial technology with the advantages of random digital patterning,excellent precision and fast printing speed,which is considered to have great potential in solar cell fabrication.Many efforts have been devoted to developing inkjet-printed OSCs and PVSCs,and much progress has been achieved in the last few years.In this review,we first introduced the working principle of inkjet printing,the rheology requirements of inks,and the behaviors of the droplets.We then summarized the recent research progresses of the inkjet-printed OSCs and PVSCs to facilitate knowledge transfer between the two technologies.In the end,we gave a perspective on inkjet-printed OSCs and PVSCs.

ZnO Surface Passivation with Glucose Enables Simultaneously Improving Efficiency and Stability of Inverted Polymer:Non-fullerene Solar Cells

The power conversion efficiency(PCE)of polymer solar cells(PSCs)has exceeded 19%due to the rapid progress of photoactive organic materials,including conjugated polymer donors and the matched non-fullerene acceptors(NFAs).Due to the high density of oxygen vacancies and the consequent photocatalytic reactivity of ZnO,structure inverted polymer solar cells with the ZnO electron transport layer(ETL)usually suffer poor device photostability.In this work,the eco-friendly glucose(Glu)is found to simultaneously improve the efficiency and stability of polymer:NFA solar cells.Under the optimal conditions,we achieved improved PCEs from 14.77%to 15.86%for the PM6:Y6 solar cells.Such a PCE improvement was attributed to the improvement in J_(SC) and FF,which is ascribed to the smoother and more hydrophobic surface of the ZnO/Glu surface,thereby enhancing the charge extraction efficiency and inhibiting charge recombination.Besides,UV-Vis absorption spectra analysis revealed that glucose modification could significantly inhibit the photodegradation of Y6,resulting in a significant improvement in the stability of the device with 92%of its initial PCE after aging for 1250 h.The application of natural interface materials in this work brings hope for the commercial application of organic solar cells and provides new ideas for developing new interface materials.