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Extensive studies have been conducted regarding mother tongue (L1) interference and developing English writing skills. This study, however, aims to investigate the influence of the Spanish language on second language (L2) writing skills at several Ecuadorian senior high schools in Loja. To achieve this, 351 students and 42 teachers from second year senior high schools (public and private) were asked to participate in this study. The instruments for data collection were student and teacher questionnaires, as well as a written test in which students were asked to write a narrative passage. The information gathered from the instruments was then organized and tabulated to determine the various interference variables. Afterwards, the most representative samples from the narrative texts were analyzed based on their semantic, morphological and syntactical features. The results from this study indicate that English grammar and vocabulary were the linguistic areas that suffered the highest level of L1 language interference. The most common Spanish interference errors were misuse of verbs, omission of personal and object pronouns, misuse of prepositions, overuse of articles, and inappropriate/ unnatural word order. Finally, some suggestions are given to teachers in order to help students prevent further Spanish interference problems during writing/composition classes.

Large‐scale manufacturing of perovskite solar cells (PSCs) requires the deposition of homogeneous and defect‐free perovskite films on large‐area substrates. Up to now, the knowledge developed for industrial slot‐die processing has not been fully transferred to the perovskite photovoltaic community. Here, the deposition of uniform perovskite layers by slot‐die coating (SDC). Computer fluid dynamics (CFD) simulations, experimental validation, and calculation of industrial uniformity parameters are demonstrated, which enabled to establish processing conditions for SDC of perovskite ink. This approach allowed for obtaining stable cross‐web flow in the slot‐die head resulting in the formation of a stable coating bead yielding uniform perovskite films. The best processing parameters are used for the fabrication of slot‐die‐coated PSCs, which showed a more homogeneous spatial distribution of photovoltaic parameters compared to their spin‐coated counterparts. Better reproducibility observed in device performance is a step forward toward the commercialization of perovskite photovoltaic technology. For the first time, the industrial approach used for the optimization of slot‐die coating is applied for the processing of perovskite inks that have special conditions such as low viscosity and in situ crystallization on the substrate. [ABSTRACT FROM AUTHOR]

Perovskite solar technology stands on three different pillars: efficiency, stability, and processability. Focusing on processability, the field demands the achievement of optoelectronic grade active layers with high uniformity fabricated by industry‐compatible methods. Herein, the design and implementation of an air knife on a blade coating deposition system, which allows controlling the evaporation rate of the solvents improving the crystallization and uniformity of perovskite films in a p–i–n device are reported. The effect of doctor blade operational parameters is studied using image analysis combined with a machine learning method to identify the most relevant processing variables leading to a uniform perovskite layer with optimal thickness. After implementing the air knife system and finding the best processing conditions, a special perovskite solar minimodule enabling the evaluation of single inner subcells is fabricated. These perovskite subcells reach an average efficiency of 10.1% and remarkably all the subcells deviate less than 20% from this value over a large‐area substrate. These results demonstrate the promising potential of this fabrication method for low cost and high deposition rate photovoltaic devices, which is on the path to mass production. [ABSTRACT FROM AUTHOR]

In this work, we have synthesized and fabricated solar cells with the hybrid metal halide compounds with the general formula ABX3, where the A cation is methylammonium, the B cation is nickel, and the X anion is chlorine or a mixture of chlorine and iodine. We obtained experimental evidence that this material is a semiconductor with an orthorhombic crystalline structure which pertains to the space group Cmcm. The bandgap can be modulated from 1.4 eV to 1.0 eV by changing the chlorine anion to iodine. Therefore, we were able to obtain solar cells with efficiencies up to 0.16% with the CH3NH3NiCl2I composition. We have also studied by means of first-principles calculations, taking into account van der Waals dispersive forces, the ground state properties of these materials such as their crystal structure and formation and decomposition energies. We have found that these energies are lowered by the lighter mass anion, and the calculated decomposition energies show that only CH3NH3NiCl3 is stable with respect to the most probable decomposition pathway. The electronic band structure and band edge alignments have been calculated using quasiparticle effects through the GW0 approximation; these materials show an indirect bandgap with the valence band maxima at −6.93 and −5.49 eV with respect to vacuum and the conduction band minima at −5.62 and −4.60 eV with respect to vacuum for CH3NH3NiCl3 and CH3NH3NiI3, respectively. This work provides a pathway to explore new hybrid A + B 2 + X 3 − -type semiconductor materials. [ABSTRACT FROM AUTHOR]