Semitransparent Perovskite Solar Cells with an Evaporated Ultra‐Thin Perovskite Absorber

Abstract

Metal halide perovskites are of great interest for application in semitransparent solar cells due to their tunable bandgap and high performance. However, fabricating high‐efficiency perovskite semitransparent devices with high average visible transmittance (AVT) is challenging because of their high absorption coefficient. Here, a co‐evaporation process is adopted to fabricate ultra‐thin CsPbI3 perovskite films. The smooth surface and orientated crystal growth of the evaporated perovskite films make it possible to achieve 10 nm thin films with compact and continuous morphology without pinholes. When integrated into a p‐i‐n device structure of glass/ITO/PTAA/perovskite/PCBM/BCP/Al/Ag with an optimized transparent electrode, these ultra‐thin layers result in an impressive open‐circuit voltage (VOC) of 1.08 V and a fill factor (FF) of 80%. Consequently, a power conversion efficiency (PCE) of 3.6% with an AVT above 50% is demonstrated, which is the first report for a perovskite device of a 10 nm active layer thickness with high VOC, FF and AVT. These findings demonstrate that deposition by thermal evaporation makes it possible to form compact ultra‐thin perovskite films, which are of great interest for future smart windows, light‐emitting diodes, and tandem device applications.

Doping with KBr to Achieve High-Performance CsPbBr3 Semitransparent Perovskite Solar Cells

“…The challenge of PSCs in BIPV lies in concurrently achieving high power conversion efficiency (PCE) and reasonable AVT. 4,5 A common strategy to address this challenge involves the utilization of ultrathin films, 6,7 micropatterned films, 8,9 and wide bandgap films. 10,11 Among these, wide-bandgap semitransparent perovskite, particularly CsPbBr 3 , exhibits nearly 85% transmittance in the visible light range from 530 to 780 nm (Figure S1) and remarkable moisture and heat resistance.…”

“…In recent years, perovskite solar cells (PSCs) have emerged as key applications for building-integrated photovoltaics (BIPV). − According to prevalent standards and regulations governing facade glass curtain walls, an average visible light transmittance (AVT) exceeding 40% is required. The challenge of PSCs in BIPV lies in concurrently achieving high power conversion efficiency (PCE) and reasonable AVT. , A common strategy to address this challenge involves the utilization of ultrathin films, , micropatterned films, , and wide bandgap films. , Among these, wide-bandgap semitransparent perovskite, particularly CsPbBr 3 , exhibits nearly 85% transmittance in the visible light range from 530 to 780 nm (Figure S1) and remarkable moisture and heat resistance. − Consequently, CsPbBr 3 devices can achieve an AVT surpassing 40%, while maintaining a higher PCE.…”

Facile Preparation of Large-Area, Ultrathin, Flexible Semi-Transparent Perovskite Solar Cells via Spin-Coating

“…Another alternative is mesh-assisted deposition which leads to a similar microstructure with partial coverage of the perovskite film on the substrate which is achieved by controlled growth in a grid structure. − The major disadvantage of these two methods, putting aside the additional processing step, is that electron- and hole-transporting materials (ETM and HTM respectively) are in direct contact. Quite recently preparation of conformal perovskite 10 nm layer using vacuum evaporation has been reported . Despite promising results, the entire fabrication process is much more complex, though, and therefore more challenging for scaling up.…”

“…Quite recently preparation of conformal perovskite 10 nm layer using vacuum evaporation has been reported. 20 Despite promising results, the entire fabrication process is much more complex, though, and therefore more challenging for scaling up. Hence, the preparation of sub-100 nm perovskite films with a conformal profile in the wet process is still a challenge.…”

Research Progress of Semi-Transparent Perovskite and Four-Terminal Perovskite/Silicon Tandem Solar Cells

“…Reproduced with permission: Copyright 2011, Royal Society of Chemistry. (h) Schematic illustration of perovskite film deposition via thermal evaporation method[33]. Reproduced with permission: Copyright 2023, John Wiley and Sons.…”