The preparation method of double-blade coating to ‘write’ high efficiency perovskite solar cells

Perovskite solar cells are promising because of its high efficiency, low cost and solution processable property. In this paper, a double-blade slot-die coating method based on the mechanism of fountain pen was brought out to deliver the precursor to substrate conveniently. The controllable ‘writing’ process reduces precursor waste and improves film quality. After annealing, uniform and efficient perovskite films were achieved. Optimum condition of the doctor-blade film was explored. By adjusting precursor concentration, champion MAPbI3 device with 19.7% PCE was obtained. This work provides a new idea for preparing high quality perovskite film suitable for large-scale industrial production.