Effect of Antisolvent Contact Time in Micropipette-Controlled Spin-Coating of Perovskite Layers on Solar Cell Efficiency

This study investigates the effect of the contact time of chlorobenzene, when used as an antisolvent, on the formation of perovskite layers during spin-coating.The contact time of chlorobenzene is controlled by adjusting the drop rate and dispensing volume using an apparatus developed in our laboratory that combines a spin coater and micropipette.X-ray diffraction (XRD) results show no significant change in the crystal structure of perovskite when chlorobenzene is added in the contact time range of 0.3 to 2.0 s, during the spin-coating preparation using the antisolvent method.However, as the contact time with chlorobenzene increases, the grain size decreases, and the power conversion efficiency (PCE) also decreases accordingly.Reducing the drop rate, regardless of the amount of chlorobenzene used, allows sufficient time for the formation of larger crystals, thereby improving the PCE.These results highlight the importance of controlling the contact time with the antisolvent to optimize solar cell performance.