Nutri-priming as an efficient means to improve the agronomic performance of molybdenum in common bean (Phaseolus vulgaris L.)

International audienceMicroelements play important roles in improving crop productivity and quality. Two traditional methods of providing micronutrients are soil and foliar application, yet the cost involved and phytotoxicity risks poses a major challenge in most global agricultural areas. Nutri-priming represents thus a very promising and viable alternative to ensure that the plants' requirements for micronutrients are met. This paper explores the Mo-priming effects on the germination, growth and yield components of common bean (Phaseolus vulgaris L.). In order to accomplishthis research objective, our study is divided in two phases. The first phase seeks to determine the effects of two durations (5 and 10 h) of Mo-priming on the germination parameters. Then, a greenhouse pot experiment was conducted with primed seeds showing better germination performance to assess the effects of Mopriming on certain parameters related to biological nitrogen fixation and crop yield. Five seed pretreatments were studied, namely, 0, 0.025, 0.05, 0.1 and 0.2% of ammonium heptamolybdate ((NH4)6Mo7O24.4H2O). Unprimed seeds treated with or without the recommended dose through a soil application were used as controls. Hydropriming is sufficient to improve seed germination performance. However, 0.1% Mo-priming for 10 h improved the net CO2 assimilation rate, chlorophyll content and biological nitrogen fixation. Six times more nitrogen was fixed (65.8 kg ha−1) in these plants than in the controls. Additionally, grain yield increased by 115% compared to the negative control. Thus, compared to soil intake, nutri-priming was a very efficient experimentalmethod

Characterization of nanostructured ZnO grown by linear sweep voltammetry

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Impact of iodide substitution on the physical properties and stability of cesium lead halide perovskite thin films CsPbBr3-xIx (0 <= x <= 1)

[EN] This study sheds light on the effect of iodide substitution on the structural and optical properties of solution processed mixed cesium lead perovskite thin films CsPbBr3-xIx (0 <= x <= 1) as well as their atmospheric and thermal stability. Pawley fit indicated that the mixed lead halide CsPbBr(3-x)l(x) perovskite crystallizes in the orthorhombic (Pnma) space group. X-ray diffraction analyses showed a shift to lower angles when the average fraction of iodide incorporated increased indicating the expansion of the lattice. Absorbance measurements show that the CsPbBr3-xIx films exhibit a very high absorbance in the visible and short infrared region. The band gap of CsPbBr(3-x)l(x) is tuned from 238 (CsPbBr3) to 2.17 eV (CsPbBr2I1) following the Vegard's law. CsPbBr3 films showed a bright photoluminescence with emission maximum at 530 nm CsPbBr(3-x)l(x) films demonstrate excellent stability after aging for two days in a humid environment (relative humidity of 60%) and under thermal annealing at relatively high temperature. (C) 2017 Elsevier B.V. All rights reserved.This work was supported by Ministerio de Economia y Competitividad (ENE2013-46624-C4-4-R) and Generalitat Valenciana (Prometeus 2014/044).Atourki, L.; Vega-Fleitas, E.; Mollar García, MA.; Marí, B.; Kirou, H.; Bouabid, K.; Ihlal, A. (2017). Impact of iodide substitution on the physical properties and stability of cesium lead halide perovskite thin films CsPbBr3-xIx (0 <= x <= 1). Journal of Alloys and Compounds. 702:404-409. https://doi.org/10.1016/j.jallcom.2017.01.205S40440970

Effects of Na2SO4 on the optical and structural properties of Cu2ZnSnS4 thin films synthesized using co-electrodeposition technique

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Effect of doping on the phase stability and photophysical properties of CsPbI2Br perovskite thin films

[EN] In this study, we demonstrate that the crystallization process of CsPbI2Br films can be modulated when small amounts of additives are added to the precursor solution, leading to the formation of the bright brownish a-phase perovskite films with high orientation along the [100] crystallographic direction. Doped CsPbI2Br films exhibit improved crystallinity, with high coverage, large grain size and pinhole-free surface morphology, suitable for making high performance optoelectronic devices. We also explored the role of Cl in the photophysical properties of CsPbI2Br perovskite films using the temperature dependent photoluminescence technique. We found that the Cl ions enhance the photoluminescence emission by reducing the density of trap states, and also decrease the exciton binding energy from (22.3) meV to (11.2) meV. We believe this work contributes to understanding the effect of doping on the crystallization process with an in-depth insight into the photophysical properties of the cesium-based perovskite materials.Atourki, L.; Marí, B.; Makha, M.; Bouabid, K.; Regragui, M.; Ihlal, A.; Abd-Lefdil, M.... (2021). Effect of doping on the phase stability and photophysical properties of CsPbI2Br perovskite thin films. RSC Advances. 11(3):1440-1449. https://doi.org/10.1039/d0ra08912e1440144911

Annealing Effect on One Step Electrodeposited CuSbSe2 Thin Films

The purpose of this work is to study the influence of the annealing temperature on the structural, morphological, compositional and optical properties of CuSbSe2 thin films electrodeposited in a single step. CuSbSe2 thin films were grown on fluorine-doped tin oxide (FTO)/glass substrates using the aqueous electrodeposition technique, then annealed in a tube furnace under nitrogen at temperatures spanning from 250 to 500 &deg;C. The resulting films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis, Raman spectroscopy and UV-Vis spectrophotometer. The annealing temperature plays a fundamental role on the films structural properties; in the range 250&ndash;350 &deg;C the formation of pure CuSbSe2 phase from electrodeposited binary selenides occurs. From 400 to 500 &deg;C, CuSbSe2 undergoes a preferential phase orientation change, as well as the increasing formation of copper-rich phases such as Cu3SbSe3 and Cu3SbSe4 due to the partial decomposition of CuSbSe2 and to the antimony losses

Role of the chemical substitution on the structural and luminescence properties of the mixed halide perovskite thin MAPbI3-xBrx (0:1) films

Mixed bromide iodide lead perovskites were prepared from methylamine, lead nitrate and the corre- sponding hydroX acid (X = I, Br), they were then deposited as thin films on ITO substrate by the spin coating process. X-ray diffraction analyses indicated the formation of a tetragonal phase I4/mcm up to x = 0.4 and a cubic perovskite with space group Pm3 m in the composition range of 0.6-1. Mixed lead perovskites showed a high absorbance in the UV vis range. The band gap energy of thin films were estimated from absorbance spectral measurements, it was found that the onset of the absorption edge for MAPbI3- x Brx (x < 1) thin films is ranging between 1.58 to 1.72 eV. Photoluminescence emission energies for mixed halide perovskites presented intermediate values from 781 nm (MAPbI3 ) to 545 nm (MAPbBr3 ).This work was supported by Ministerio de Economia y Competitividad (ENE2013-46624-C4-4-R) and Generalitat valenciana (Prometeus 2014/044).Atourki, L.; Vega-Fleitas, E.; Marí, B.; Mollar García, MA.; Hassan Ait Ahsaine; Bouabid, K.; Ihlal, A. (2016). Role of the chemical substitution on the structural and luminescence properties of the mixed halide perovskite thin MAPbI3-xBrx (0:1) films. Applied Surface Science. 371:112-117. https://doi.org/10.1016/j.apsusc.2016.02.207S11211737