Materials for perovskite solar cell (PSC) are being developed as possible contenders for the upcoming photovoltaics generation. However, despite their high efficiency, perovskite materials containing lead are not suitable for commercialization due to their toxic nature. As a result, tin (Sn)-based perovskites have emerged as a promising alternative. Tin-based perovskites possess similar ionic sizes to lead and exhibit exceptional light absorption properties. Nevertheless, these materials are hindered by the oxidation from Sn2+ to Sn4+, which results in poor stability and suboptimal conversion efficiency. This review provides a comprehensive exploration of the oxidation mechanism of Sn2+ and presents an in-depth discussion of recent advancements in various strategies aimed at preventing this oxidation in FASnI3 PSCs.

The efficiency of perovskite solar cells (PSCs) has sparked interest in both academic and industrial circles. The existence of charge traps within the perovskite film, as well as charge recombination occurring at grain boundaries and defects in PSCs, significantly limits the power conversion efficiency (PCE). In this study, we investigate the introduction of a novel organic passivating layer on the perovskite surface, with the goal of enhancing the performance and stability of perovskite solar cells. Through experimentation, we assessed the incorporation of this organic passivating layer on the perovskite film using various solvents and discovered that toluene is the most effective solvent for both the preparation and utilization of this passivating layer in PSCs.

One of the emerging technologies in photovoltaic research is organic–inorganic metal halide perovskite solar cells (PSCs). PSCs have a maximum power conversion efficiency (PCE) of >25%, which is comparable to traditional silicon solar cells. Even though perovskite solar cells have demonstrated excellent performance in recent years, commercialization remains a long way off. The presence of unstable hole transporting layers (HTLs) is one of the primary reasons for this. As a result, further development of PSCs toward scalable production remains heavily reliant on the development of innovative low-cost, high-efficiency materials that can be used as HTLs. We discussed the recent advances in various types of organic and inorganic HTLs in this review. The effect of these hole-transporting materials (HTMs) on cell performance and stability in particular has been summarised in order to provide some guidance for the future development of PSCs.

Degradation of perovskite solar cells is shown to be partly reversible in the dark, which significantly affects the lifetime of the cell under operational conditions. In this contribution, complex interplay between reversible and irreversible degradation is discussed on the basis of indoor illumination-recovery experiments and outdoor exposure to natural diurnal cycle. We demonstrate that both photo-degradation and subsequent recovery processes are strongly affected by the electrical bias condition during the aging. Light-induced ion migration and metastable traps formation with different dominance under different biases and at different degradation stages might explain observed features.

The operational stability of perovskite solar cells (PSCs) remains a limiting factor in their commercial implementation. We studied the long-term outdoor stability of ITO/SnO2/Cs0.05((CH3NH3)0.15(CH-(NH2)2)0.85)0.95PbI2.55Br0.45/spiro-OMeTAD/Au cells, as well as the dynamics of their degradation, under simulated sunlight indoors and their recovery in the dark. The extent of overall degradation was found to depend on processes occurring both under illumination and in the dark, i.e., during the daytime and nighttime, with the dynamics varying with cell aging. Full recovery of efficiency in the dark was observed for cells at early degradation stages. Further cell degradation resulted in recovery times much longer than one night, appearing as irreversible degradation under real operational conditions. At later degradation stages, very different dynamics were observed: short-circuit current density and fill factor exhibited a pronounced drop upon light turn-off but strong improvement under subsequent illumination. The interplay of reversible and irreversible degradation processes with different recovery dynamics was demonstrated to result in changes in the cell’s diurnal PCE dependence during its operational lifespan under real sunlight conditions.

We report on utilizing free-standing hybrid perylenediimide/carbon nanotube (PDI/CNT) films fabricated in air as back contacts for fully inorganic perovskite solar cells (glass/FTO/dense TiO2/mesoporous TiO2/CsPbBr3/back electrode). The back contact electrode connection is performed by film transfer rather than by vacuum deposition or by wet processing, allowing the formation of highly homogeneous contacts under ambient conditions. The use of this novel electrode in solar cells based on CsPbBr3 resulted in efficiency of 5.8% without a hole transporting layer; it is significantly improved in comparison to the reference cells with standard gold electrodes. Overall device fabrication can be performed on air, using inexpensive processing methods. The hybrid film electrodes dramatically improve the cell photo-stability under ambient conditions and under real-life operating conditions outdoors. The champion unencapsulated device demonstrated less than 30% efficiency loss over 6 weeks of outdoor aging in Negev desert conditions. The CNT/PDI electrodes offer the combination of fabrication simplicity, unique contacting approach, high efficiency and good operational stability for perovskite photovoltaics.

Degradation rates in perovskite solar cells (PSCs) were previously shown to be bias dependent; however, little is known about the mechanisms and driving factors that account for such degradation. Herein, stability studies under concentrated sunlight are demonstrated as a powerful experimental methodology to investigate bias-dependent PSC degradation mechanisms. Stress testing of encapsulated PSCs' stability shows that light intensity is more significant than the illumination dose for PSC degradation under short-circuit (SC) conditions, whereas the dose is the determining factor under open-circuit (OC) stressing. This indicates that different degradation mechanisms are dominant under different bias conditions. It is postulated that degradation at SC biasing is dominated by ion migration, facilitated by photogenerated defects. Degradation at OC biasing can be explained by photogenerated radicals acting as nonradiative recombination centers (charge traps), which are created via reactions with accumulated charge carriers. Trap formation upon OC biasing is in accordance with degradation of photoluminescence and OC voltage (V-OC) observed under this stress. A combination of multiple mechanisms, all with reduced driving forces compared with OC /SC biasing, explains degradation at maximum power point biasing. Understanding the bias effect on PSC stability can elucidate the underlying degradation mechanisms and lead to routes to reduce them.

Understanding degradation mechanisms in halide perovskite solar cells is the key aspect to achieve a breakthrough in photovoltaics.

The development of hybrid organic-inorganic halide perovskite solar cells (PSCs) that combine high performance and operational stability is vital for implementing this technology. Recently, reversible improvement and degradation of PSC efficiency have been reported under illumination-darkness cycling. Quantifying the performance and stability of cells exhibiting significant diurnal performance variations is challenging. We report the outdoor stability measurements of two types of devices showing either reversible photo-degradation or reversible efficiency improvement under sunlight. Instead of the initial (or stabilized) efficiency and T-80 as the figures of merit for the performance and stability of such devices, we propose using the value of the energy output generated during the first day of exposure and the time needed to reach its 20% drop, respectively. The latter accounts for both the long-term irreversible degradation and the reversible diurnal efficiency variation and does not depend on the type of process prevailing in a given perovskite cell.

Here, the role of two different solvents viz. chloroform (CHCl3) and chlorobenzene (CB) for the formation and dissolution of honeycomb‐structured conductive polymer poly[2,5‐bis [3‐N,N‐diethylamino)−1‐oxapropyl]‐1,4‐phenylenevinylene] (P1) thin films was demonstrated. Surface morphology of the films was investigated using atomic force microscopy (AFM) and it was confirmed that CB was a suitable solvent to obtain a better honeycomb structure over the CHCl3. Also, the film dissolution studies were carried out by immersing the honeycomb structured polymer films in their respective solvents for the specified interval of time, which show that the rate of film dissolution was prominent in CB than CHCl3. Based on the solvent selection, honeycomb structured blend as well as heterojunction (HJ) films were prepared from P1 and EG‐C60 (1:1 wt/wt). Here, morphological studies clearly confirmed that the EG‐C60 molecules were uniformly present only at the nodes and frames of the honeycomb structured blend film (which avoids the formation of exciton pair recombination of polymer), whereas in case of heterojunction film EG‐C60 molecules were unevenly distributed, this discovery could find use in fully exploiting the potential of various material systems, and open up new opportunities to improve the efficiency of OSCs. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1207–1214, 2016

Trihydrazone-functionalized cyanopyridine liquid crystals are introduced into the photoactive layer as processing additives to acquire an improved interpenetrating network and charge carrier mobility.

Molecular electronics has been growing rapidly to a point where the ambition is to miniaturize conventional electronic devices down to the single-molecule scale. We construct a molecular scale electronic device based on a donor-acceptor antenna (DAA) system composed of an electron donating quantum dots (QDs) and electron accepting C 60 coupled via an aminoalkanethiol bridge. The DAA system was fabricated by a self-assembly procedure, and the charge transfer (CT) rate and charge discharge (CD) efficiency are demonstrated. The CT rate that we obtained for our DAA system is 776 × 10 6 s -1 , which is ten times greater than the reported value. Photoluminescence excitation data, PL lifetime, and intensity trajectory data show that strong CT occurs from the QD to the C 60 PTA, and this thin DAA film (<;100 nm) device can hold photogenerated charges for almost 3 h before complete dissipation when not connected to an external circuit, which can have a positive impact on the application of these DAA-based device in molecular electronics. We anticipate that our findings will catalyze the development of new lightweight solar battery.

Polyaniline -Polyisoprene composites were prepared by chemical method. The Polyaniline particles were of nanometer size. The characterization of the PANI-Polyisoprene composite were done by UV-visible spectrometer, Dynamic light scattering and Keithly source meter. The size of the polyaniline particles was found to be 23.29 nm. The electrical properties of the sandwich structure using ITO-Polyisoprene-PANI-Al indicated that the composite can find application in microelectronics.