On the effect of poly(3-hexylthiophene) regioregularity on inkjet printed organic solar cells

Abstract

We investigate the impact of P3HT regioregularity on the performance of bulk heterojunction solar cells with inkjet printed P3HT:PCBM layers. Three polythiophenes with different regioregularities ranging from 93% up to 98% are inkjet printed from two different formulations at room temperature. It is found that the high RR-P3HT (98%) is not suitable for inkjet printing at room temperature. The fast formation of aggregates shortens the shelf life of the ink and thus, results in low reliability of the printing process, in the formation of inhomogeneous and very rough films with surface roughnesses up to 70 nm, and in a strongly reduced device performance. This phenomenon is not observed for solar cells processed via the doctor blading technique. Nevertheless, inkjet printing of 96% RR-P3HT:PCBM oDCB/mesitylene solutions at room temperature resulted in solar cells with 3.5% efficiency, while doctor blading of 98% RR-P3HT:PCBM oDCB/mesitylene solutions resulted in efficiencies as high as 4.4%.

Fully Inkjet‐Printed Organic Photodetectors with High Quantum Yield

“…We were able to print stripes fully covering the silver lines (necessary to avoid short circuits between electrodes), with an average thickness of about 120 nm and a coffee stain free profi le. Looking at the absorbance spectral shape and focusing on the region where P3HT dominates the absorption (450 nm-650 nm), we observe the presence of a well-developed shoulder at 610 nm, suggesting the presence of ordered regions DOI: 10.1002/adma.201303473 of P3HT, [ 36 ] likely due to the use of a large fraction of a relatively high boiling point solvent in the ink formulation (1,2-dichlorobenzene boils at 180.5 °C). [ 37 ] For the deposition of the top semi-transparent electrode we adopted a highly conductive inkjet formulation based on PEDOT:PSS (Clevios P Jet N).…”

Organic Solar Cell by Inkjet Printing—An Overview

“…For organic devices, the use of inkjet printing technology is exceptionally encouraging because of the compatibility with different substrates [11]. As appeared in the in Figure 3 [14], the ink has been removed from a head to the substrate without direct contact with the surface [23]. …”

Fabrication of Annealing-Free High Efficiency and Large Area Polymer Solar Cells by Roller Painting Process

“…To overcome these problems, various methods for fabrication of PSCs have been proposed including doctor blading [14,15], ink-jet printing [16], spray coating [17][18][19][20], screen printing [21] and brush painting [22]. Although these processes have an advantage for fabrication of large area films and exhibit comparable performance to the spin coating, the thickenss control and inhomogeneity of the film still remain unsolved.…”