Executive Summary : | Hybrid metal halide perovskites are currently more attractive materials among various emerging semiconductors due to their exceptional properties including tunable bandgap (1.4-2.4 eV), large absorption coefficient (104-105 cm-1), high carrier mobility (66 cm2V-1s-1), long carrier diffusion length (1μm), long carrier lifetime (273 ns) and low exciton binding energy (less than 50 meV). These properties make metal halide perovskites excellent candidates for optoelectronic applications, such as photovoltaic solar cells, light-emitting diodes, lasers, photodetectors, transistors, and energy storage devices. Particularly, perovskite solar cells (PSCs) have experienced rapid development within the emerging thin-film photovoltaics (PV). Surprisingly, the power conversion efficiency has been rapidly improved from an initial 3.8% to a most recently certified 25.2% within the last decade, however, most of the high efficiency was achieved at a very small active area of less than 0.1 cm2. To bring the perovskite solar cell (PSC) technology toward industrial applications, large-area (greater than 10 cm2) perovskite solar modules with multiple sub-cells need to be developed by fully scalable deposition approaches. Perovskite film deposition methods play a vital role for the fabrication of large-area devices. Various coating methods have been applied to deposit large-area individual or mixed perovskites, including blade, D-bar, slot-die, spray and inkjet coating, as well as screen printing, stamping, spin coating, dip coating and vacuum deposition. However, large-scale deployment PSCs will also require the ability to produce large-area, uniformly high-quality perovskite films. Perovskite film deposition methods play a vital role in the fabrication of large-area devices. Unfortunately, the device area increased to mini-module scale, the efficiency record dropped dramatically. For example, when the active area of the device is increasing from 0.1cm2 to 25 cm2 the efficiency of 25% of perovskite solar cells dropped to 12-15% under the same condition. The inherent causes are mainly ascribed to inadequate quality control of large-area perovskite thin films. To bring the perovskite solar cell (PSC) technology toward industrial applications, large-area (higher than10 cm2) perovskite solar modules with multiple sub-cells need to be developed by fully scalable deposition approaches. In the current stage of PSCs research and development, to overcome this major obstacle is in urgent need before this new technology could realize scale-up industrialization. |