Fast Light-Cured TiO₂ Layers for Low-Cost Carbon-Based Perovskite Solar Cells

To push perovskite solar cells (PSCs) as efficient solution-based solar cells with remarkable photovoltaic properties into large-scale production, in addition to improving efficiency and stability, reducing the fabrication cost, and especially increasing the manufacturing speed, is crucial. In this research, we have replaced the conventional heating and sintering procedure of a bilayer (compact and mesoporous) TiO2 electron transport layer as a highly time- and energy-consuming process with a fast light-curing procedure for use in PSCs with a promising printable CuInS2/carbon hole collector. A halogen-tungsten lamp (H-lamp, 1 kW) and a mercury lamp (M-lamp, 400 W) are utilized as low-cost available sources. Results show that sintering occurs effectively in the case of light-curing using the H-lamp for 5 min as a replacement of conventional heating in the furnace at 500 °C. In the case of light-curing using the M-lamp for 20 min or heating in the furnace at 400 °C, sintering does not occur effectively and the mesoporous TiO2 layer acts as a scaffold for the perovskite layer. The effective sintering does not affect efficiency (that is 16.1 to 16.4% in the reverse scan for all the optimized samples); however, it affects hysteresis as a result of preventing charge accumulation at the interface.