The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10. 1002/aenm.201700414. used mesoporous TiO 2 ESLs, but the complex synthesis procedure and requirement of sintering at temperatures above 450 °C make the process undesirable for large-scale roll-to-roll manufacturing. [3] Therefore, significant efforts have been made on developing efficient low-temperature planar PVSCs. [23][24][25][26][27] For PVSCs with a regular configuration, the more popular low-temperature processed ESL materials are transition metal oxides such as TiO 2 , [26,28] ZnO, [29,30] SnO 2 , [31,32] and Zn 2 SnO 4 . [23,24] Due to its relatively simple synthesis process, chemical stability, [33][34][35] and high electron mobility, [33,36,37] SnO 2 ESL has shown great promise in making efficient planar PVSCs. For example, Ke et al. first fabricated PVSCs with PCE over 16% using a low-temperature solution processed SnO 2 ESL. [31] Since then, many other groups have also reported efficient PVSCs using low-temperature processed ESLs. [23,33,37] Recently, Gratzel and co-workers reported planar PVSCs with efficiencies approaching 21% using SnO 2 ESLs synthesized by low-temperature chemical bath deposition. [32] Low-temperature SnO 2 ESLs have been deposited by various methods including spin-coating, [31] dual-fuel combustion, [38] chemical-bath deposition, [32] and atomic-layer deposition (ALD). [34,39] ALD produces the most compact thin films compared to the other methods mentioned. However, PVSCs using ALD SnO 2 ESLs often show current-density-voltage (J-V) Adv. Energy

No abstract

No abstract

No abstract

Although epitaxial growth is the fundamental method to realize lattice matched heterojunctions in electronics manufacturing, large-scale epitaxial single crystal layers based on solution-processing have rarely been reported. Here, cascade organic−inorganic hybrid perovskite single crystals with purity quotient over 99.9% consisting of chlorine, bromine, and iodine are fabricated by solution-processed epitaxial growth, in which the mismatch rate between adjacent layers is less than 1%. The area of solution-processed epitaxial growth is proved up to 4 cm 2 , and the speed reaches nearly 100 nm s −1 . The resulting high-quality interface effectively improves bonding between adjacent layers, and the average mobility is calculated to be over 200 cm 2 V −1 s −1 in samples with different structures. Based on a specific structure with n-type, p-type, and intrinsic layers, a 7.55 mm-thickness X-ray photodiode with sensitivity 1.58 μC mGy −1 cm −2 is fabricated. This work provides a different method for fabricating solution-processed based electronic devices and makes stable perovskite-based devices more accessible.