Search

Perovskite solar cells (PSC) have shown a rapid increase in efficiency than other photovoltaic technology. Despite its success in terms of efficiency, this technology is inundated with numerous challenges hindering the progress towards commercial viability. The crucial one is the anomalous hysteresis observed in the photocurrent density‐voltage (J−V) response in PSC. The hysteresis phenomenon in the solar cell presents a challenge for determining the accurate power conversion efficiency of the device. A detailed investigation of the fundamental origin of hysteresis behavior in the device and its associated mechanisms is highly crucial. Though numerous theories have been proposed to explain the causes of hysteresis, its origin includes slow transient capacitive current, trapping, and de‐trapping process, ion migrations, and ferroelectric polarization. The remaining issues and future research required toward the understanding of hysteresis in PSC device is also discussed. [ABSTRACT FROM AUTHOR]

Mixed metal halide perovskites are gaining paramount interest due to efficient band gap tenability and improved optical properties compared to their single metal halide perovskites. It is thus valuable to investigate compositional changes in lead halide perovskites to explore energy changes. Herein, we report the synthesis of a lead to lead free hybrid perovskite solid solution (CH3NH3Pb1−xCuxBr3) as nanoparticles and films. The increasing concentration of Cu2+ ions in the site of the Pb2+ ion in the perovskite shifted the diffraction peaks to a larger angle. Uniform spherically shaped nanoparticles were synthesized by a wet chemical method, the higher Cu2+ concentration leads to agglomeration, producing sheet like morphologies. However, the deposition of thin films of CH3NH3Pb1−xCuxBr3 perovskite solid solution shows that well defined morphologies begin to appear with increasing concentrations of Cu2+ in the perovskite structure. The as-prepared bulk lead free CH3NH3CuBr3 perovskite shows a band gap of 1.65 eV. A blue shift in photoluminescence (PL) was observed with copper enriched hybrid perovskites. [ABSTRACT FROM AUTHOR]

This contribution reports the deposition of new zinc based lead free all inorganic 3D CsZnCl2I perovskite thin films using aerosol assisted chemical vapour deposition (AACVD) at 100 °C. Room tempertaure optical measurements performed on the as-deposited thin films showed two absorption peaks. Upon 325 nm excitation, the CsZnCl2I perovskite thin film showed broad band white light emission having two peaks, which cover the entire visible range of the spectrum. This is the first example of white light emission from 3D all-inorganic lead free mixed halide CsZnCl2I perovskites. [ABSTRACT FROM AUTHOR]

Abstract: Inorganic halide perovskite (CsPbX3) nanostructures have gained considerable interest in recent years owing to their enhanced stability and optoelectronic applications. Recent developments in the synthesis of nanostructures are reviewed. The impact of the precursor and ligand nature, temperature and growth time on the morphology and shape tuning of CsPbX3 nanostructures is described in relation to their optical properties. The presynthetic and postsynthetic anion exchange strategies to retain pre‐existing crystal phase and shape are discussed in this minireview. [ABSTRACT FROM AUTHOR]

We report the preparation of a lead free inorganic perovskite by a facile wet-chemical method using HCl as a solvent at room temperature. The cesium perovskite CsCuCl3 material was characterized by powdered X-ray diffraction (p-XRD), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray (EDX) spectroscopy. Ultraviolet/Visible (UV-Vis) and steady state photoluminescence (PL) spectroscopy were also carried out on the material. CsCuCl3 showed promising optical properties with a band gap of 2.6 eV. The material was tested as a fluorescent sensor for the detection of metal ions and as a selective fluorescent chemodosimeter for Pb2+ ions. The substitution of Cu2+ ions by Pb2+ in CsCuCl3 proves the success of the chemodosimetry approach for the detection of Pb2+ ions. [ABSTRACT FROM AUTHOR]

Hybrid perovskite have shown a potential as structurally and chemically tunable materials with interesting optical properties. Herein, We describe the synthesis and characterization of two new perovskites, hydroxyl ammonium lead iodo chloride, OHNH3PbI2Cl (1) and hydroxyl ammonium lead chloride, OHNH3PbCl3 (2) by wet-chemical route. The as-prepared (1) and (2) have shown promising optical properties with suitable band gaps 3.7eV and 3.9eV respectvely. Time resolved Photoluminescence (PL) results showed that hybride pervoskite (2) had a long lived PL whereas (1) exhibited a short PL life-time. Thermo-gravimetrical analysis (TGA) in nitrogen gas environment revealed that (1) and (2) are stable and do not show any sign of decomposition up to ~200oC. Photocatalytical performance of as-prepared materials (1) and (2) under sunlight were mointerted using textile dye direct yellow. The compound (1) degraded dye in 20min while (2) in 55min with superior recyclablity. [ABSTRACT FROM AUTHOR]

We report a facile approach to prepare nanostructures of all-inorganic perovskite CsPbBr 2 I by the wet chemical and aerosol assisted chemical vapour deposition (AACVD) methods using oleylamine (OLA) as a shape modifier. This study explores the role of OLA during the formation of nanosquares via both methods. [ABSTRACT FROM AUTHOR]

We report the facile synthesis of cesium copper bromide (CsCuBr 3 ) in HBr solvent at room temperature. The perovskite material was successfully used as a sensor to detect the water contamination in dimethylformamide (DMF). [ABSTRACT FROM AUTHOR]