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Abstract Controlling crystal growth alignment in low-dimensional perovskites (LDPs) for solar cells has been a persistent challenge, especially for low-n LDPs (n 1.7 eV) impeding charge flow. Here we overcome such transport limits by inducing vertical crystal growth through the addition of chlorine to the precursor solution. In contrast to 3D halide perovskites (APbX3), we find that Cl substitutes I in the equatorial position of the unit cell, inducing a vertical strain in the perovskite octahedra, and is critical for initiating vertical growth. Atomistic modelling demonstrates the thermodynamic stability and miscibility of Cl/I structures indicating the preferential arrangement for Cl-incorporation at I-sites. Vertical alignment persists at the solar cell level, giving rise to a record 9.4% power conversion efficiency with a 1.4 V open circuit voltage, the highest reported for a 2 eV wide band gap device. This study demonstrates an atomic-level understanding of crystal tunability in low-n LDPs and unlocks new device possibilities for smart solar facades and indoor energy generation.

Abstract Interface engineering is the core of device optimization, and this is particularly true for perovskite photovoltaics (PVs). The steady improvement in their performance has been largely driven by careful manipulation of interface chemistry to reduce unwanted recombination. Despite that, PVs devices still suffer from unavoidable open circuit voltage (VOC) losses. Here, we propose a different approach by creating a photo-ferroelectric perovskite interface. By engineering an ultrathin ferroelectric two-dimensional perovskite (2D) which sandwiches a perovskite bulk, we exploit the electric field generated by external polarization in the 2D layer to enhance charge separation and minimize interfacial recombination. As a result, we observe a net gain in the device VOC reaching 1.21 V, the highest value reported to date for highly efficient perovskite PVs, leading to a champion efficiency of 24%. Modeling depicts a coherent matching of the crystal and electronic structure at the interface, robust to defect states and molecular reorientation. The interface physics is finely tuned by the photoferroelectric field, representing a new tool for advanced perovskite device design.

Electro-optical spectroscopy is nowadays a routine approach for the analysis of light induced properties and dynamical processes in matter, whose understanding is particularly crucial for the intelligent design of novel synthetic materials and the engineering and optimization of high-impact optoelectronic devices. Currently, within this field, it is the common choice to rely on multiple commercial setups, often costly and complex, which can rarely combine multiple functions at the same time with the required sensitivity, resolution, and spectral tunability (in both excitation and detection). Here, we present an innovative, compact, and low-cost system based on “three in one” components for the simultaneous electro-optical material and device characterization. It relies on compact fiber-coupled Fourier transform spectroscopy, the core of the system, enabling a fast spectral analysis to acquire simultaneously wavelength and time resolved photoluminescence (PL) maps (as a function of the time and wavelength), PL quantum yield, and electroluminescence signal. Our system bypasses conventional ones, proposing a new solution for a compact, low-cost, and user-friendly tool, while maintaining high levels of resolution and sensitivity.

The paper introduces a modified version of the demographic balance equation commonly used in human demography in the study of populations of permanent crops. The proposed methodology is then applied to analyzing the evolution of the Italian vineyard.In short, the study measures different factors that have had an impact on the extension of the Italian vineyard and on its age structure such as the reduced investments in new plantations; the massive early explant and also the extended life of the vineyards since they are kept in production well beyond the conventional limit of their economic life. Results show that the reduction of the area cultivated with grapes in Italy is due to different reasons, some of which relate to the past while others mirror more recent behaviors of vine growers.The methodology also allows the prediction of tendencies in the future. Three scenarios are built, based on different hypothesis about new investments and explantation rates that account for the wine EU CMO 2013–2030. Projections show, that in the next decades, both the extension of cultivated area and plant age will be deeply influenced by choices that had been made even decades before. Comparing the results obtained under the different hypothesis, helps to assess the range of possible impacts of the new policy framework.In an increasingly global and competitive market, the analysis proposed provides original insights on some future waves in the wine industry both to policy makers and stakeholders. This awareness is especially needed in order to put in place strategies aimed at avoiding supply-demand mismatches in a sector where supply moves slowly while demand trends are fast and almost unpredictable. Keywords: Demographic trends, Future scenarios, Italian vineyards