Chemical vapor deposition growth and photodetector performance of lead-free all-inorganic crystalline Cs3Sb2X9 (X = I, Br) perovskite thin filmsElectronic supplementary information (ESI) available: Schematic diagrams showing the synthesis of Cs3Sb2X9 perovskite thin films by a two-step CVD method. Unit cells and 2D layered structures of Cs3Sb2I9 and Cs3Sb2Br9 perovskite thin films. XRD spectra of as grown and annealed films. 3D view AFM images of Cs3Sb2I9 and Cs3Sb2Br9 perovskite thin films. Compositional analysis of Cs3Sb2I9 and Cs3Sb2Br9 perovskite thin films using XRF spectra. Ellipsometric experimental and simulated spectra of Ψ and Δ for Cs3Sb2I9 and Cs3Sb2Br9 perovskite thin films. Schematic representation of the surface photovoltage (SPV) in a p-type semiconductor. Schematic diagram and optical image of the Cs3Sb2X9 perovskite film photodetector. Photoresponse curves with different illumination power densities and bias voltages. Wavelength dependent photoresponse. Compositional stability after 45 days of storage under ambient conditions. Reproducible on/off response of Cs3Sb2I9 and Cs3Sb2Br9 film photodetectors after 45 days of storage under ambient conditions, and XRF data with different molar ratios. See DOI: https://doi.org/10.1039/d2tc05289j

Chemical vapor deposition growth and photodetector performance of lead-free all-inorganic crystalline Cs3Sb2X9 (X = I, Br) perovskite thin filmsElectronic supplementary information (ESI) available: Schematic diagrams showing the synthesis of Cs3Sb2X9 perovskite thin films by a two-step CVD method. Unit cells and 2D layered structures of Cs3Sb2I9 and Cs3Sb2Br9 perovskite thin films. XRD spectra of as grown and annealed films. 3D view AFM images of Cs3Sb2I9 and Cs3Sb2Br9 perovskite thin films. Compositional analysis of Cs3Sb2I9 and Cs3Sb2Br9 perovskite thin films using XRF spectra. Ellipsometric experimental and simulated spectra of Ψ and Δ for Cs3Sb2I9 and Cs3Sb2Br9 perovskite thin films. Schematic representation of the surface photovoltage (SPV) in a p-type semiconductor. Schematic diagram and optical image of the Cs3Sb2X9 perovskite film photodetector. Photoresponse curves with different illumination power densities and bias voltages. Wavelength dependent photoresponse. Compositional stability after 45 days of storage under ambient conditions. Reproducible on/off response of Cs3Sb2I9 and Cs3Sb2Br9 film photodetectors after 45 days of storage under ambient conditions, and XRF data with different molar ratios. See DOI: https://doi.org/10.1039/d2tc05289j