Apreo lovac

Morphologies of the perovskite films were imaged with a scanning electron microscope (SEM, FEI Apreo LoVac). The crystal structure was characterized by Bruker D8 Advance X‐ray diffractometer (XRD) with Cu Kα radiation at 40 kV and 40 mA. PL lifetime was measured by the time‐correlated single photon counting method with an Edinburgh Instruments FLS980 fluorescence spectrometer. The excitation source used was a picosecond pulsed diode laser at 532 nm.
The current density‒voltage (J‒V) curves of PSCs were recorded using a Keithley 2400 source measurement unit and a Newport solar simulator (ORIEL‐SOI3A) with an AM1.5G spectrum. All of flexible photovoltaic devices were measured in the flatten state. The light intensity was adjusted to 100 mW cm⁻² using standard Si cell (91150V). Both forward and reverse scans were measured with the scanning speed of 0.15 V s⁻¹. The EQE spectra were measured in DC mode on a spectrum corresponding system (Enlitech QE‐R), calibrated by Si reference solar cell.
The EL spectrum and ERE of the perovskite LED were recorded simultaneously by a commercialized system (XPQY‐EQE‐350‐1100, Guangzhou Xi Pu Optoelectronics Technology Co., Ltd.) that is equipped with an integrated sphere (GPS‐4P‐SL, Labsphere) and a photodetector array (S7031‐1006, Hamamatsu Photonics).

The film morphologies were characterized by SEM (FEI Apreo LoVac). The optical properties were measured by UV–vis spectrophotometer (Agilent Tech, Cary 5000). XRD and GIXRD: XRD measurements were performed by a Bruker D8 Advance X‐ray diffractometer with Cu Kα as the radiation source. GIXRD pattern was performed with incidence angle of 0.5° and five consecutive measurements were collected and averaged into single spectra. TEM and HRTEM: Samples for TEM were prepared by ablating the device using a focused ion beam microscope. Pt layers were deposited on top of the device for protection. TEM and HRTEM images were taken on a JEOL JEM 3200FS TEM at 300 kV. AFM and KPFM: The AFM and KPFM measurements were performed on a Bruker Dimension Icon with Nanoscope V controller. All the KPFM images were collected in lift mode by using SCM–PIT probes with a spring constant of 2.8 N m⁻¹ and a resonant frequency of 78.3 kHz. During all KPFM measurements, the optimal lift height is 30 nm. UPS and XPS: UPS and XPS characterizations were obtained with a Thermo Fisher Scientific K‐Alpha⁺, using the HeI (21.22 eV) emission line and Al Kα radiation (1486.6 eV). X‐ray photoelectron depth profiling spectra were recorded by using Ar⁺ sputtering gun operated at 3 keV, rastering a 2.0 × 2.0 mm² area with 5 s postetch delays.