No abstract

Herein, we examine the impact of cations on the structural, morphological, optical properties and degradation of lead perovskite APbI3 (where A = MA, FA, Cs). Its structure, surface morphology and optical properties have been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Visible spectrometer. The structure of perovskite thin films was found to be in the direction of (110) plane. It is seen from the XRD results that this kind of cation assumes a significant part in stabilising and improving the performance of APbI3 based solar cells. Here, the cesium lead iodide thin films show a smooth and homogenous surface and enormous grain size without pinhole perovskite film. An optical investigation uncovered that the band gap is in a range from 1.4 to 1.8 eV for the different cations. Additionally, in ~60% humidity under dark conditions for two weeks, the structural and optical properties of CsPbI3 films remained good. Furthermore, the efficiency of FTO/TIO2/CSPbI3/Spiro-Ometad/Au solar cells was calculated to be 21.48%.

Antisolvent quenching has shown to significantly enhance several perovskite films used in solar cells; however, no studies have been conducted on its impact on MASnI3. Here, we investigated the role that different antisolvents, i.e., diethyl ether, toluene, and chlorobenzene, have on the growth of MASnI3 films. The crystallinity, morphology, topography, and optical properties of the obtained thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) measurements, and UV–visible spectroscopy. The impact of the different antisolvent treatments was evaluated based on the surface homogeneity as well as the structure of the MASnI3 thin films. In addition, thermal annealing was optimized to control the crystallization process. The applied antisolvent was modified to better manage the supersaturation process. The obtained results support the use of chlorobenzene and toluene to reduce pinholes and increase the grain size. Toluene was found to further improve the morphology and stability of thin films, as it showed less degradation after four weeks under dark with 60% humidity. Furthermore, we performed a simulation using SCAPS-1D software to observe the effect of these antisolvents on the performance of MASnI3-based solar cells. We also produced the device FTO/TiO2/MASnI3/Spiro-OMeTAD/Au, obtaining a remarkable photoconversion efficiency (PCE) improvement of 5.11% when using the MASnI3 device treated with chlorobenzene. A PCE improvement of 9.44% was obtained for the MASnI3 device treated with toluene, which also showed better stability. Our results support antisolvent quenching as a reproducible method to improve perovskite devices under ambient conditions.

Hybrid organic–inorganic halides are considered as outstanding materials when used as the absorber layer in perovskite solar cells (PSCs) because of its efficiency, relieve of fabrication and low‐cost materials. However, the content of lead (Pb) in the material may origin a dramatic after effect on human's health caused by its toxicity. Here, we investigate replacing the lead in MAPbI3 with tin (Sn) to show its influence on the growth of the film nucleation and stability of the solar device based on MASnI3. By analysing the manufactured perovskite films by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), UV–visible absorption, photoluminescence (PL) and atomic force microscopy (AFM), the properties of the thin films when lead is replaced by tin are reported. The simulation run for the case of MAPbI3 is reported, where Voc = 0.856 V, Jsc = 25.65 mA cm−2, FF = 86.09%, and ETA = 18.91%, and for MASnI3, Voc = 0.887 V, Jsc = 14.02 mA cm−2, FF = 83.72%, and ETA = 10.42%. In perovskite‐based devices using MASnI3 as absorber, it was found to be more stable despite of its lower efficiency, which could be improved by enhancing the bandgap alignment of MaSnI3. The results of this paper also allow the development of a new, reliable production system for PSCs.

This work reported the successive incorporation of tetrabutylammonium (TBA) into Methylammonium lead Iodide (MAPbI3) perovskite. The thin films were characterized by X-Ray diffraction (XRD), Scanning electron microscopy (SEM), Transmittance electron microscopy (TEM), Atomic force microscopy (AFM), and UV-Visible spectroscopy. It was shown that introducing TBA increases the crystallinity, grain size, surface morphology without pin-hole, and roughness of the MAPbI3 thin films. Moreover, the MA(1-X)TBAX PbI3 thin film shows better stability in a relative humidity of ∼60% after 15 days than the pure MAPbI3 thin film. The obtained results are hoped to be helpful for stability and improvement of the performance of the MAPbI3 thin films by doping TBA cations under ambient conditions.