[en] Lewis acid nature of SnCl/sub 4/ and n-Bu/sub 2/ SnCl/sub 2/ has been studied using 3-methyl-1-indanone. The equilibrium constant has been calculated for both the tin moieties. It has been found that Lewis acid character of SnCl/sub 4/ is fourteen times greater than that of n-Bu/sub 2/SnCl/sub 2/. (author)

[en] Over a short period of approximately 10 years, metal-halide-perovskite-based photovoltaics have demonstrated unprecedented improvements in solar cell performance beyond the various major photovoltaic semiconductor materials such as organic, cadmium telluride, and copper indium gallium selenide. With this, the current focus lies on the commercialization of perovskite solar cell technology and the issues encountered while ensuring and balancing high efficiency, stability, and eco-friendliness in the photovoltaic community. This article reviews prominent developments in perovskite-based photovoltaic power generation based on the ABI${}_3$ structure, describing the current state and understanding of state-of-the-art solar cell drives. Accordingly, methods to improve the efficiency and long-term operational stability, lead toxicity, nonlead perovskites, bandgap optimization, and tandem solar cells are discussed. Prospects and views on future research considering the feasibility of perovskite technology commercialization are provided. (© 2023 The Authors. Advanced Energy and Sustainability Research published by Wiley‐VCH GmbH)

[en] Despite their advantageous attributes, such as a narrow bandgap and reduced toxicity, tin-lead halide perovskites (TLHPs) have received limited attention due to their lower power conversion efficiency (PCE) relative to lead-only variants. In this study, a transformative approach is introduced that leverages perovskite quantum dots (PQDs) to optimize TLHP solar cells. While conventional oleyl-capped PQDs enhance the open circuit voltage (V${}_{OC}$), the long-chain ligands hinder charge transport. To overcome this limitation, a post-treatment with isopropyl alcohol effectively dissociates these ligands and PQD crystals, resulting in reduced defect density, improved charge transfer, and elevated quasi-Fermi level splitting in the TLHP device. Consequently, the PCE of the device is notably increased from 19.0% to 23.74% and elevated the V${}_{OC}$ from 0.78 to 0.87 V, without compromising the photocurrent or fill factor. The findings highlight PQD modification as a compelling avenue for TLHP solar cell enhancement, particularly in boosting V${}_{OC}$. (© 2024 Wiley‐VCH GmbH)

[en] Short communication

[en] Although tin halide perovskite has shown excellent photoelectric performance, its efficiency of solar cell is low compared with that of lead halide. In order to enhance the efficiency of tin halide perovskite solar cell, a deep understanding of the role of the defects in the perovskite absorption layer and at the electron transport layer (ETL)/absorber or absorber/hole transport layer (HTL) interface is very necessary. In this work, the planar heterojunction-based CH₃NH₃SnI₃ perovskite solar cells were simulated with the SCAPS-1D program. Simulation results revealed a great dependence of device efficiency on defect density and interface quality of the perovskite absorber. The defect density at the front interface is critical for high efficiency, and the polarity of the interface charge has a different impact on the device efficiency. Strikingly, an efficiency over 29% was obtained under the moderate simulation conditions. (paper)

[en] Thin film solar cell materials such as 3D metal halide perovskites are cheaper alternatives to silicon. Presently, the conversion efficiency of 3D lead halide perovskites is 25.5% (2021), which represents an increase of more than 550% since their discovery in 2009 (3.8%). Despite this remarkable progress, concerns about the toxicity of lead have sparked the quest for possible substitutes, in particular, 3D tin halide perovskites. This review covers the general properties of tin halide perovskites, synthesis and stability. It also identifies possible gaps and application beyond solar cells. (author)

[en] It has been a widely-known and intractable issue due to very rapid degradation of tin (Sn) based organic-inorganic hybrid perovskites (OIHPs). To incorporate organic chain polymers into the OIHPs based photo-active polycrystalline films seems to be a unique strategy to passivate naturally formed defects at grain boundaries and surfaces, to prevent surface oxidation, and consequently, to optimize photovoltaic performance, as well as to tackle with device instability. In this work, a Lewis-type organic insulating polymer, polymethylmethacrylate (PMMA), was utilized as an effective additive in formamidinium tin tri-iodide (FASnI₃) precursor solutions, and the corresponding solid films were made by a one-step processing method. By tuning different concentrations of PMMA, the solar cells have exhibited remarkable improvements of and FF by comparing with a control device without PMMA. The role of PMMA is functional for surface morphology optimization, trap density reduction and current density–voltage (J–V) hysteresis elimination. As a result, it is helpful to effectively impede degradation speeds of FASnI₃ based solar cells. (paper)

[en] This paper reports on grain boundary (GB) roles in lead-free tin halide perovskite thin films. Nano scale spatial mapping of charge separation efficiency in methylammonium tin halide (MASn(I_1−xBr_x)₃, MA = CH₃NH₃) thin films were constructed by Kelvin probe force microscopy and conductive atomic force microscopy (C-AFM). We observed downward band bending at GBs under dark conditions and higher surface photovoltage along the GBs, confirmed by C-AFM which showed high local current flows along the GBs. The band bending degree and local current intensity were affected by the Br/I ratio. Photo-generated carriers were more effectively separated and collected at GBs with increased Br content, and hysteresis was observed in Br-rich Sn-halide perovskite. (paper)

[en] Moessbauer parameters of tin compounds isolated in low temperature matrices were related to electronic properties at the tin nuclei which had been obtained by molecular orbital calculations. Stannane and its derivatives as well as tin halide compounds in low temperature matrices show good correlation between observed isomer shifts δ and calculated electron density ρ(0), and also between observed quadrupole splittings Δ E_Q and calculated electric field gradients EFG. Using correlation for the observed Moessbauer parameters and calculated electronic properties of known compounds, assignment of novel photoproduct species were confirmed and their structures determined on the basis of molecular orbital calculations. (orig.)

[en] Highlights: • We employed CsSnX₃ for Pb²⁺ via cation replacement for the first time. • Lead-free perovskite has the linear range and high selectivity. • The CsSnBr₃ QDs was successfully applied to detect Pb²⁺ in organic products. -- Abstract: Lead ion is one of the most toxic metallic pollutants, lacking of photoluminescence probe in organic products. In this work, the lead free perovskite CsSnX₃ (X = Cl, Cl/Br, or Br) quantum dots (QDs) were employed as a novel fluorescent probe for the detection of lead ion in the oily products, with high sensitivity and high selectivity. The highly enhanced photoluminescence, the red shift and the reduction of the full wavelength at half maximum (FWHM) of emission spectra of CsSnX₃ QDs were observed after adding Pb²⁺ ions, originating from the substitution of Sn²⁺ by Pb²⁺ ions in situ. A wide dynamic range from 1 × 10⁻⁸ M to 1 × 10⁻² M and a low limit of detection (3.5 × 10⁻⁹ M) were obtained. Finally, the CsSnBr₃ QDs was successfully employed to probe Pb²⁺ ions in mask, hair dye, nail polish and oil paint. Our probe provides a promising device to detect Pb²⁺ ions in organic solution system.