Homogeneous and highly controlled deposition of low viscosity inks and application on fully printable perovskite solar cells

Abstract

The fully printed, hole-transporter-free carbon perovskite solar cell structure incorporating a triple mesoscopic layer has emerged as a possible frontrunner for early industrialisation. It is an attractive structure because it can be fabricated by the simple sequential screen printing and sintering of titania, zirconia, and carbon. The device is finalised by manual dropping of a perovskite precursor solution onto the carbon which subsequently infiltrates. This stage in device fabrication is inhomogeneous, ineffective for large areas, and prone to human error. Here we introduce an automated deposition and infiltration system using a robotic dispenser and mesh which delivers the perovskite precursor uniformly to the carbon surface over a large area. It has been successfully used to prepare perovskite solar cells with over 9% efficiency. Cells, prepared by this robotic mesh deposition, showed comparable performance to reference cells, made by standard drop deposition, confirming this approach to be effective and reliable. X-ray diffraction and Raman spectroscopy were used to confirm the uniformity of the deposition over a large area. ARTICLE HISTORY

All Printable Perovskite Solar Modules with 198 cm2 Active Area and Over 6% Efficiency

“…When working on large area substrates, it is important to avoid unnecessary thermal stress which can cause distortion of the substrate making it difficult to get a homogeneous printing of the thin (i.e., 800 nm) m‐TiO 2 across the large area. For this reason, the spraying of the compact TiO 2 blocking layer, both unpatterned and patterned, was carried out at 150 °C, rather than at 300 °C as per our standard fabrication method, before printing the mesoporous TiO 2 and sintering both layers at 550 °C.…”

Investigating the Superoxide Formation and Stability in Mesoporous Carbon Perovskite Solar Cells with an Aminovaleric Acid Additive

“…The samples were prepared by screen‐printing commercially available pastes as described earlier 28,29. The perovskite solutions were drop‐casted on the different architectures, left at room temperature for 10 min, and then annealed at 50 °C for 1 h.…”

“…The lack of an expensive organic HTL such as 2,2′,7,7′‐tetrakis[ N , N ‐di(4‐methoxyphenyl)amino]‐9,9′‐spirobifluorene and the absence of a metal back contact, usually thermally evaporated silver or gold, make these devices potentially low cost 27. It has also been demonstrated that it is possible to screen‐print the mesoporous layers over large areas making it suitable for mass production 25,28–30. In the first demonstration, Ku et al obtained a 6.6% PCE device stable over 840 h in the dark using MAPI perovskite.…”

Outstanding Indoor Performance of Perovskite Photovoltaic Cells – Effect of Device Architectures and Interlayers

“…The AVA‐MAPI precursors solution was prepared with 439.0, 151.4, and 6.7 mg of, respectively PbI 2 , MAI, and 5‐AVAI in 1 mL of γ‐Butyrolactone. The solution was then deposited with the so‐called Robotic Mesh method . In this Robotic Mesh method, a robotic dispenser moves a syringe to continuously deliver the precursor solution at 12 m s −1 to a mesh which is on the top of the device to homogeneously spread the liquid on the surface.…”