All-inkjet printed large area organic solar cells deposited from environmentally friendly solvents are demonstrated for the first time.

area of large area perovskite solar cells and modules by using sheet-to-sheet (S2S) techniques. [10][11][12][13][14] Blade coating is often employed as a scalable method for the manufacturing of PSC and has demonstrated PCE values of 19-20% on cell level [15,16] and PCE values of 15.3% and 14.6% for modules with aperture areas of 33.0 and 57.2 cm 2 , respectively. [16] Monolithic perovskite modules with an active area of 70 cm² and with a PCE of 10.74% were fabricated using scalable printing processes. [12] S2S slot die coated solar cells on a glass substrate with the efficiency of 11.96% were demonstrated by Hwang et al. [11] and 5 × 5 cm 2 modules with PCE of 10.6% were demonstrated by Cai et al. [17] Slot-die coated perovskite-based photovoltaic (PV) modules of 168 cm 2 with a PCE of 10% [18,19] and later the modules of 144 cm 2 with a PCE of 14.5% were in a recent press release of Solliance. [20] In order to allow the manufacturing of flexible PSCs for future high-volume production, roll-to-roll (R2R) processing technologies need to be developed. [21,22] First attempts of R2R manufacturing have been demonstrated already by some research groups. [23][24][25][26][27] A mini slot die coater built on a 3D printing platform allowed the manufacturing of flexible perovskite solar cells with up to 11.0% PCE. [25] A blowing-assisted drop-casting on flexible R2R moving substrates results in perovskite solar cells with PCE of up to 11.16%. [26] However, future mass production of the perovskite solar cells requires the development of industry compatible large area deposition methods. The technology for R2R deposition of PSC requires optimization of several parameters simultaneously, namely: 1) proper solvent choice (viscosity, boiling point, toxicity, price, etc.); 2) fast crystallization kinetics (required by the high speed of the R2R deposition) preferably in ambient atmosphere; 3) layer uniformity over the large area; 4) PCE of the devices, etc. Hence, a dedicated optimization of the R2R drying and annealing conditions, which heavily contribute to the abovementioned issues, will be needed. The current study is the first successful example of large area R2R manufacturing of PSC in ambient condition using nontoxic solvents. The developed processes are compatible with industrial manufacturing on a plastic substrate. The stabilized efficiencies of the manufactured devices reached the record value of 13.5%. Using prototype industrial processes and equipment with optimized in-line R2R coating, drying, and annealing, the results of this study will help in bringing the PSC technology one step closer to future commercialization.The feasibility of upscaling the perovskite solar cells technologies to high volume production using roll-to-roll (R2R) slot die coating is demonstrated in this study. Perovskite solar cells are produced by R2R slot die coating on flexible substrates with a width of 30 cm and the web speed of 3-5 m min −1 . R2R deposition of the electron transport layer and perovskite is performed at ambient atmospher...

Composites of piezoelectric particles in a polymer matrix with enhanced properties in the poling direction were prepared by dielectrophoretic alignment of the particles. The effect of processing parameters such as the amplitude and frequency of the applied electric field and the viscosity of the matrix on the dielectric and piezoelectric properties of the cured composite were demonstrated for a composite with a PZT volume fraction of 0.2. The amount of structuring could be correlated to the dielectric and piezoelectric properties of the composite through the P 2 order parameter for the average particle chain orientation, which was derived from image analysis of the microstructure. The piezoelectric properties of the aligned composites can be described with a new model for composites containing particles arranged into chains. The model predictions are in good agreement with the experimental results.