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Wide bandgap perovskites have recently gained attention owing to their physical properties, versatility, and potential in various optoelectronic devices including LEDs, detectors, and building‐integrated photovoltaics (BIPV). However, BIPV materials must meet conflicting requirements, necessitating high performance, high transparency in the visible spectrum and color neutrality. This study investigates the controlled addition of chlorine in FAPb(Br1‐xClx)3 perovskites to achieve band gaps exceeding 2.4 eV. Increasing chlorine content from xCl = 0.00 to xCl = 0.25 widens the band gap from 2.37 to 2.52 eV, effectively improving the visible light transparency. Advanced characterization techniques including X‐ray diffraction, synchrotron radiation photoelectron spectroscopy, photoluminescence imaging, and fast transient absorption spectroscopy, complemented by density functional theory, reveal insights into absorption properties, electronic structure, and ultrafast recombination dynamics as a function of the thin film chemical composition. Furthermore, this study evaluates energetic disorder, carrier recombination rates, and non‐radiative losses for different compositions by extracting quantitative parameters such as Urbach energy and quasi‐Fermi level splitting, offering novel insights and guidelines for the design and optimization of emerging photovoltaic (PV) materials. Optimal PV performance metrics are achieved with a wide bandgap bromine perovskite containing 14% chlorine, striking a balance between morphology, transparency, and voltage losses. [ABSTRACT FROM AUTHOR]

Efficient semi‐transparent solar cells can extend the adoption of photovoltaics beyond standard utility‐scale, commercial, or residential applications. Halide perovskites are particularly suitable in this respect owing to their tunable bandgap. The main drawbacks in the development of transparent perovskite solar cells are the high open‐circuit voltage (Voc) deficit and the difficulties in depositing high‐quality thin films over large area substrates, given the low solubility of bromide and chloride precursors. In this work, passivation strategies are developed for the high bandgap Br perovskite able to reduce charge recombination and consequently improve the Voc. The study demonstrates 1 cm2 perovskite solar cells with Voc up to 1.73 V (1.83 eV Quasi Fermi Level Splitting) and a PCE of 8.1%. The average visible transmittance (AVT) exceeds 70% by means of a bifacial light management and a record light utilization efficiency (LUE) of 5.72 is achieved. Moreover, the potential use of the technology is evaluated toward Internet of Things (IoT) application owing to a bifaciality factor of 87% along with 17% PCE under indoor lighting. Finally, the up‐scaling is demonstrated by fabricating 20 cm2 active area modules with PCE of 7.3% and Voc per cell up to 1.65 V. [ABSTRACT FROM AUTHOR]

We reported the comparative studies of the optimization of solution-processable tungsten trioxide (WO3) as a hole transporting layer (HTL) in inverted organic photovoltaics (OPVs) using spin coating, slot-die coating, and spray coating technologies for scaling-up applications. To facilitate the technology's transition into commercial manufacturing, it is necessary to explore the role of scalable technologies for low-cost and efficient device fabrication. We investigated the role of diluting WO3 with isopropanol as an HTL in inverted OPVs to solve the issue of poor wettability of the hydrophobic surface of the PBDB-T: ITIC bulk heterojunction layer. The optimal dilution ratios of WO3 with isopropanol were 1:4, 1:4 and 1:8 with spin coating, slot-die coating and spray coating techniques, respectively. We evaluated the device performance by conducting a current density–voltage (J-V) analysis, incident photon-to-current conversion efficiency (IPCE) measurements, and ultraviolet–visible (UV-Vis) absorbance spectra for various WO3 concentrations. The J-V characteristics revealed that slot-die coating resulted in the highest performance, followed by the spray coating technology. We further investigated the impact of the annealing temperature on device performance for both slot-die- and spray-coated diluted WO3. The highest device performance was achieved at an annealing temperature of 120 °C for both coating technologies. This research offers valuable insights into the scalable fabrication of inverted OPV devices, paving the way for cost-effective and efficient large-scale production. [ABSTRACT FROM AUTHOR]

The article offers information on the advancements in perovskite solar cells (PSCs), emphasizing their efficiency improvements over the past decade. Topics include the exploration of various strategies to enhance the quality of the perovskite layer, such as using excess precursors, additives, or passivating agents.

Thin films based on scandium oxide (Sc2O3) were deposited on silicon substrates to investigate the thickness effect on the reduction of work function. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), energy dispersive X-ray reflectivity (EDXR), atomic force microscopy (AFM), and ultraviolet photoelectron spectroscopy (UPS) measurements were performed on the films deposited by electron-beam evaporation with different nominal thicknesses (in the range of 2–50 nm) and in multi-layered mixed structures with barium fluoride (BaF2) films. The obtained results indicate that non-continuous films are required to minimize the work function (down to 2.7 eV at room temperature), thanks to the formation of surface dipole effects between crystalline islands and substrates, even if the stoichiometry is far from the ideal one (Sc/O = 0.38). Finally, the presence of BaF2 in multi-layered films is not beneficial for a further reduction in the work function. [ABSTRACT FROM AUTHOR]

High-dimensionality Ruddlesden-Popper (RP) perovskites, with general formula R2An-1BnX3nþ1 and high n values (n =5), are regarded as viable materials for photovoltaics because they feature higher stability if compared to the 3D perovskite, i.e., ABX3, still maintaining good charge absorption and transport properties. When integrated into the actual solar cells, however, scattered, sometimes contradictory results are reported among different deposition procedures and different cations, especially for higher n resulting in not uniformmorphology and mixed composition. Herein, high-dimensionality RP perovskites with n = 1, 4, 10, 20, and 40 values are systematically investigated considering the interplay between the formation of 2D domains, their distribution along the active layer, the active layer thickness, and the solar cells' performance. Given the complexity of the investigated system, combined advanced structural/morphological analyses are performed to explain solar cells' performance, finding that the 2D phase segregates at the interface with the top electrode, acting as a barrier for charge extraction, overall decreasing the shortcircuit current (Jsc). Reducing the relative amount of bulky alkylammonium cation with respect to the methylammonium, the 2D perovskite overlayer is intentionally decreased leading to a recovery of the Jsc values, corroborating the hypothesis. [ABSTRACT FROM AUTHOR]

Perovskite photovoltaics (PVs) is an emerging PV technology that attracts interest thanks to an unprecedented combination of properties, including the ease of the bandgap tunability. The feasibility to deploy wide bandgap absorbers (>2.2 eV) leading to high average visible transmittance (AVT) is particularly intriguing for building-integrated PVs, in particular for smart windows, façades, and agrivoltaics. However, research on this topic is still at the initial stage, especially concerning the development of scalable deposition techniques. Uniform coverage and morphology control of bromide perovskite film are the main issues to tackle. Herein, a systematic study on the development of FAPbBr3-based semitransparent perovskite solar cell (ST-PSC) is presented by replacing spin-coating as the main deposition technique used for the device fabrication. To tackle this topic, the blade coating technique is employed to obtain a manufacturing flow performed at low temperature in the air environment. The results for the bladecoated device show a power conversion efficiency of 5.8%, AVT of 52.3%, and bifacial factor of 86.5%. Moreover, scalable and uniform FAPbBr3 deposition on 300 cm2 substrates is presented for the first time. The combination of low temperature, scale-up capability, and air processing along with promising PV performances represent a feasible platform for the future exploitation of PSC in building integrated photovoltaic. [ABSTRACT FROM AUTHOR]

We report a study of angular magnetic properties of high-anisotropy [L1.sub.0] CoPt (111) films having a tilted magnetic easy axis configuration without an oblique-grain microstructure. In particular, we investigated the field dependence of remanent magnetization while rotating the magnetic field inside three intersecting planes. The out-of-plane tilting of the [L1.sub.0] c-axis (the easy axis of the tetragonal cell) was induced by using a Pt (111) underlayer deposited onto a single-crystal MgO substrate in a conventional frontal pulsed laser deposition (PLD). The observed behavior is consistent with the presence of four easy axes with mutually orthogonal in- plane projections, symmetrically tilted at 36[degrees] with respect to the film plane. Such a system can be used, like a common single- axis tilted medium, to record information in perpendicular mode, lowering the writing field to approximately 75% of the value along the easy direction, while still maintaining the high thermal stability typical of the [L1.sub.0] alloy. Moreover, the in-plane charge compensation arising from this easy axis arrangement when a perpendicular writing field is applied may favor a media noise reduction and better performance with respect to a single-axis tilted system. Index Terms--EDXD, [L1.sub.0] CoPt (111), PLD, tilted magnetic recording.

A systematic energy dispersive X-ray reflectometry study of different ruthenium phtalocyanine (RuPc)(sub 2) thin films was performed in order to investigate their reactivity with the oxidizing NO(sub x) gas. A preliminary ex situ analysis, consisting of the comparison between the morphological parameters of different films, before and after the exposure to the gas, was performed.

The experiment was done where the X-ray reflectometry technique in its energy dispersive variant (EDXR) is used to study the morphological characteristics of dimeric ruthenium phthalocyanine thin films. The study gives information on the gas diffusion process through the film and the mechanisms of interaction between the film and gas molecules.