Wafer-scale single-crystal perovskite patterned thin films based on geometrically-confined lateral crystal growth

Abstract

We report a facile roll-printing method, geometrically confined lateral crystal growth, for the fabrication of large-scale, single-crystal CH3NH3PbI3 perovskite thin films. Geometrically confined lateral crystal growth is based on transfer of a perovskite ink solution via a patterned rolling mould to a heated substrate, where the solution crystallizes instantly with the immediate evaporation of the solvent. The striking feature of this method is that the instant crystallization of the feeding solution under geometrical confinement leads to the unidirectional lateral growth of single-crystal perovskites. Here, we fabricated single-crystal perovskites in the form of a patterned thin film (3 × 3 inch) with a high carrier mobility of 45.64 cm2 V−1 s−1. We also used these single-crystal perovskite thin films to construct solar cells with a lateral configuration. Their active-area power conversion efficiency shows a highest value of 4.83%, which exceeds the literature efficiency values of lateral perovskite solar cells.

Recent Progress in Single‐Crystalline Perovskite Research Including Crystal Preparation, Property Evaluation, and Applications

“…Recently, the Sung group developed a geometrically confined lateral crystal growth method to prepare wafer‐scale single‐crystalline perovskite film. By using a more efficient electron collection electrode, PCBM/Ag and Au electrode, a lateral solar cell based on single‐crystalline perovskite achieved a PCE up to 4.83% 111. Since there are gaps between the single‐crystalline perovskite strips reported in this work, improving the coverage of single‐crystalline perovskite film is helpful for device performance.…”

“…Using the same strategy, the Wan and Kuang groups obtained extremely thin perovskite wafers approximately 10 µm 62, 86, 110. Alternatively, to a rigid template, a soft template has also been used to modulate the crystal growth 111. Tuning the wettability of the precursor, a liquid knife method has been proposed to prepare high‐quality perovskite crystal arrays on the substrate 43.…”

Single Crystals: The Next Big Wave of Perovskite Optoelectronics

“…[54][55][56][57] Being in this rergime, a onestep printing method to fabricate CH3NH3PbI3 single-crystal perovskite thin films on a wafer-scale substrate has been reported recently. 58 The enhanced carrier mobility observed in the SCPs thin film was thought to be the driving force in enhancing the performance of optoelectronic devices. 58 The propensity…”

“…58 The enhanced carrier mobility observed in the SCPs thin film was thought to be the driving force in enhancing the performance of optoelectronic devices. 58 The propensity…”

“…58,173,[180][181][182][183][184][185] The severe instabilities and the long-term stability issues arising due to the structural defects, especially dislocations and grain boundaries, impede the viable commercialization of the aforementioned devices. 58 Therefore, research is focused on employing single-crystalline films of these materials. Due to the larger grains and lower grain boundary density, perovskite monocrystalline thin films resemble SCPs in terms of their optoelectronic properties.…”