Development of cultivars of sunflower (Helianthus annuus L.) with increased levels of saturated fatty acids could increase the utility of the oil for specific edible purposes. The primary objective of this research was to induce variability for these traits by using mutagenesis. Four sunflower mutants with altered seed fatty acid compositions have been isolated by screening single M2 and M3 seeds from plants obtained from mutagenized seeds utilizing ethyl methanesulfonate, sodium azide, and x‐rays. The mutant lines included CAS‐5, which has an oil with a fivefold increase (252 g kg−1) in palmitic acid (16:0) and the appearance of palmitoleic acid (16:1; 37 g kg−1); and CAS‐3, CAS‐4, and CAS‐8, which have from two to six times (99–260 g kg−1) the stearic acid (18:0) content normally observed in the oil of cultivated sunflower. The dramatic increase in levels of either 16:0 or 18:0 were at the expense of oleic (18:1) and linoleic (18:2) acids. The relative proportion of 18:1 to 18:2 varied with the mutants. All showed variation in fatty acid composition among the seeds of the original plant, which indicated that the fatty acid changes were controlled by the genotype of the embryo. The bimodal distribution in fatty acid composition of CAS‐3 and CAS‐5 seeds suggested that major recessive genes are involved in the control of these characters.

In recent years, organo-lead-halide perovskites have emerged as promising new materials for photovoltaics, reaching high efficiencies. The excellent photoelectronic properties and easy solution processing makes the lead perovskite an ideal light harvesting material in a solar cell. In spite of these great advantages, there are concerns about the lead contained in the material because of its well-known toxicity characteristics. Obtaining new metal halide perovskites without lead is still a challenge; until now, only a few experimental reports have been published and some other theoretical calculations replacing lead by most of the possible candidates of the periodic table. In this paper, we show for the first time synthesis of the calcium hybrid perovskites CH 3 NH 3 CaI 3 and CH 3 NH 3 CaI 3−x Cl x with complementary studies based on first-principles bandstructure calculation. Crystallographic analysis shows a pseudocubic structure, and optical measurements confirms that this type of perovskite absorbs light in the UV region, which is in good agreement with the calculation that showed a band gap larger than 3.5 eV.

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In order to get homogeneous and high-quality perovskite CH 3 NH 3 PbI 3 films, different growing methods have been developed, but most of them are unsuitable for scaling up. In this work, we studied in a systematic approach the influence of CH 3 NH 3 Cl (MACl) surface treatment in the acetonitrile (ACN) deposition route. This method does not require vacuum nor solvent quenching steps, which make it probably one of the easiest for transference from lab scale to large-area deposition techniques such as roll-to-roll printing. The properties of perovskite films grown by ACN method and the influence of the MACl on the performance of the perovskite solar cells (PSCs) are characterized in detail by different techniques. By atomic force microscopy (AFM) and Kelvin probe force microscopy (KPFM) we found significant differences in the morphology and the work function of the perovskite with and without MACl treatment. Moreover, the microstructure presents very different behavior: after being exposed to radiation, the MACl treated sample presented passivated grain boundaries and higher intensity in the photoluminescence (PL) emission. The higher PL for perovskite films with MACl treatment correlates with superior photovoltaic parameters of PSCs. All these features lead to highly homogeneous perovskite layers on large areas enabling the fabrication of 10 × 10 cm 2 solar minimodules processed in air at low temperature (<100 °C). For these minimodules, we reached a PCE up to 9.2% with an aperture area of 40 cm 2 . These results demonstrate the potential of perovskite surface treatments as an effective strategy for the production of smooth, pinhole free films on large-area substrates, the gateway for further scale-up and commercialization.

The structural, electronic and magnetic properties of Zn 0. 95 Results of these studies suggest that Fe and Co ions in the Fe+Co co-doped sample has a strong synergistic effect because they eliminated the presence of impurities and gave the strongest ferromagnetic signal. Possible role of charge transfer ferromagnetism involving mixed valence ions is considered as a potential mechanism in these nanoparticles. Presence of both Co 2+ and Fe 3+ might promote more efficient charge transfer in the co-doped Zn 0.90 Fe 0.05 Co 0.05 O, leading to the enhanced ferromagnetism observed in this sample. However, more evidence is necessary to confirm the role of charge transfer ferromagnetism. This is an author-produced, peer-reviewed version of this article. The final, definitive version of this document can be found online at The Journal of Applied Physics, published by American Institute of Physics (AIP).