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The final publication is available at Springer via http://dx.doi.org/10.1007/s10008-016-3237-0. ; Abstract CuGaSe2 and CuGaS2 polycrystalline thin film absorbers were prepared by one-step electrodeposition from an aqueous electrolyte containing CuCl2, GaCl3 and H2SeO3. The pH of the solution was adjusted to 2.3 by adding HCl and KOH. Annealing improved crystallinity of CuGaSe2 and further annealing in sulphur atmosphere was required to obtain CuGaS2 layers. The morphology, topography, chemical composition and crystal structure of the deposited thin films were analysed by scanning electron microscopy, atomic force microscopy, energy dispersive spectroscopy and X-ray diffraction, respectively. X-Ray diffraction showed that the asdeposited CuGaSe2 film exhibited poor crystallinity, but which improved dramatically when the layers were annealed in forming gas atmosphere for 40 min. Subsequent sulphurization of CuGaSe2 films was performed at 400 °C for 10 min in presence of molecular sulphur and under forming gas atmosphere. The effect of sulphurization was the conversion of CuGaSe2 into CuGaS2. The formation of CuGaS2 thin films was evidenced by the shift observed in the X-ray diffraction pattern and by the blue shift of the optical bandgap. The bandgap of CuGaSe2 was found to be 1.66 eV, while for CuGaS2 it raised up to 2.2 eV. A broad intermediate absorption band associated to Cr and centred at 1.63 eV was observed in Cr-doped CuGaS2 films. ; This work was supported by Ministerio de Economia y Competitividad (ENE2013-46624-C4-4-R) and Generalitat Valenciana (Prometeus 2014/044). One of the authors (S. Ullah) acknowledges the European Union (IDEAS-Call-3, Innovation and Design for Euro-Asian scholars) for its financial support. ; Ullah, S.; Mollar García, MA.; Marí, B. (2016). Electrodeposition of CuGaSe2 and CuGaS2 thin films for photovoltaic applications. Journal of Solid State Electrochemistry. 20(8):2251-2257. https://doi.org/10.1007/s10008-016-3237-0 ; S ; 2251 ; 2257 ; 20 ; 8 ; Calixto ME, Sebastian PJ, ...

[EN] An effective n-type doping of ZnO thin films electrochemically synthetized was achieved by varying the chloride ion concentration in the starting electrolyte. The ratio between chloride and zinc cations was varied between 0 and 2 while the zinc concentration in the solution was kept constant. When the concentration of chloride in the bath increases an effective n-type doping of ZnO films takes place. n-type doping is evidenced by the rise of donors concentration, obtained from Mott-Schottky measurements, as well as from the blueshift observed in the optical gap owing to the Burstein-Moss effect. ; This work was supported by Spanish Government through MCINN grant MAT2009-14625-C03-03 and European Commission through NanoCIS project FP7-PEOPLE-2010-IRSES (ref. 269279). ; Cembrero Coca, P.; Mollar García, MA.; Singh, K.; Marí Soucase, B. (2013). Effective electrochemical n-type doping of ZnO thin films for optoelectronic window applications. Journal of Solid State Electrochemistry. 2(7):Q108-Q112. https://doi.org/10.1149/2.023307jss ; S ; Q108 ; Q112 ; 2 ; 7 ; Guill�n-Santiago, A., de la L. Olvera, M., Maldonado, A., Asomoza, R., & Acosta, D. R. (2004). Electrical, structural and morphological properties of chemically sprayed F-doped ZnO films: effect of the ageing-time of the starting solution, solvent and substrate temperature. physica status solidi (a), 201(5), 952-959. doi:10.1002/pssa.200306727 ; Oba, F., Choi, M., Togo, A., & Tanaka, I. (2011). Point defects in ZnO: an approach from first principles. Science and Technology of Advanced Materials, 12(3), 034302. doi:10.1088/1468-6996/12/3/034302 ; Oh, B.-Y., Jeong, M.-C., Lee, W., & Myoung, J.-M. (2005). Properties of transparent conductive ZnO:Al films prepared by co-sputtering. Journal of Crystal Growth, 274(3-4), 453-457. doi:10.1016/j.jcrysgro.2004.10.026 ; Manouni, A. E., Manjón, F. J., Mollar, M., Marí, B., Gómez, R., López, M. C., & Ramos-Barrado, J. R. (2006). Effect of aluminium doping on zinc oxide thin films grown by spray ...

We report on hybrid films based on ZnO/organic dye prepared by electrodeposition using tetrasulfonated copper phthalocyanines (TS-CuPc) and Eosin-Y (EoY). Both the morphology and porosity of hybrid ZnO films are highly dependent on the type of dyes used in the synthesis. High photosensitivity was observed for ZnO/EoY films, while a very weak photoresponse was obtained for ZnO/TS-CuPc films. Despite a higher absorption coefficient of TSCuPc than EoY, in ZnO/EoY hybrid films, the excited photoelectrons between the EoY levels can be extracted through ZnO, and the porosity of ZnO/EoY can also be controlled. © 2011 Moya et al. ; This study was supported by the Spanish Government through MCINN grant MAT2009-14625-C03-03, the Generalitat Valenciana through programme PROMETEO/2009/063, and the Fundacao para a Ciencia e a Tecnologia (Portugal). Thanks are due to Susie Pannell for critically reading the manuscript and providing invaluable suggestions. ; Moya Forero, MM.; ANURA SAMANTILLEKE; Mollar García, MA.; Marí Soucase, B. (2011). Nanostructured hybrid ZnO thin films for energy conversion. Nanoscale Research Letters. 6:384-389. https://doi.org/10.1186/1556-276X-6-384 ; S ; 384 ; 389 ; 6 ; ZHENG, H., PAN, Y., & XIANG, X. (2007). Oxidation of acidic dye Eosin Y by the solar photo-Fenton processes. Journal of Hazardous Materials, 141(3), 457-464. doi:10.1016/j.jhazmat.2006.12.018 ; Qazi, S. J. S., Rennie, A. R., Cockcroft, J. K., & Vickers, M. (2009). Use of wide-angle X-ray diffraction to measure shape and size of dispersed colloidal particles. Journal of Colloid and Interface Science, 338(1), 105-110. doi:10.1016/j.jcis.2009.06.006

We report on the synthesis of thin films of ZnCo 2O 4 and ZnMn 2O 4 spinels, as well as pure Co 3O 4 and Mn 3O 4 spinels, by means of electrodeposition. Spinel thin films have been analyzed by energy dispersive spectroscopy, X-ray diffraction, and Raman spectroscopy. We show that under determined deposition conditions the initial wurtzite structure of Co- and Mn-doped ZnO develops into spinel structures when the Co and Mn concentration in the films is above the solubility limit of these ions in the typical ZnO-wurtzite structure. © 2012 Elsevier Ltd. All rights reserved. ; This work was supported by Spanish Government through MICINN grants MAT2009-14625-C03-03, MAT2010-21270-C04-04 and MALTA CSD2007-0045. Financial support by the European Commission through NanoCIS project (PIRSES-GA-2010-269279) is gratefully acknowledged. Finally, we also want to acknowledge the support of Vicerrectorado de Investigacion y Desarrollo de la Universitat Politecnica de Valencia through projects UPV2011-0914 PAID-05-11 and UPV2011-0966 PAID-06-11. ; Tortosa Jorques, MD.; Manjón Herrera, FJ.; Mollar García, MA.; Marí Soucase, B. (2012). ZnO-based spinels grown by electrodeposition. Journal of Physics and Chemistry of Solids. 73(9):1111-1115. https://doi.org/10.1016/j.jpcs.2012.04.002 ; S ; 1111 ; 1115 ; 73 ; 9

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Physical Chemistry C, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.jpcc.6b06049 ; We report a study of the structural, vibrational, and electronic properties of layered monoclinic arsenic telluride (α-As2Te3) at high pressures. Powder X-ray diffraction and Raman scattering measurements up to 17 GPa have been complemented with ab initio total-energy, lattice dynamics, and electronic band structure calculations. Our measurements, which include previously unreported Raman scattering measurements for crystalline α-As2Te3, show that this compound undergoes a reversible phase transition above 14 GPa at room temperature. The monoclinic crystalline structure of α-As2Te3 and its behavior under compression are analyzed by means of the compressibility tensor. Major structural and vibrational changes are observed in the range between 2 and 4 GPa and can be ascribed to the strengthening of interlayer bonds. No evidence of any isostructural phase transition has been observed in α-As2Te3. A comparison with other group 15 sesquichalcogenides allows understanding the structure of α-As2Te3 and its behavior under compression based on the activity of the cation lone electron pair in these compounds. Finally, our electronic band structure calculations show that α-As2Te3 is a semiconductor at 1 atm, which undergoes a trivial semiconducting−metal transition above 4 GPa. The absence of a pressure-induced electronic topological transition in α-As2Te3 is discussed. ; This work has been performed under financial support from Projects MAT2013-46649-C4-2-P, MAT2013-46649-C4-3-P, MAT2015-71070-REDC, FIS2013-48286-C2-1-P, and FIS2013-48286-C2-2-P of the Spanish Ministry of Economy and Competitiveness (MINECO), and the Department of Education, Universities and Research of the Basque Government and UPV/EHU ...

The structural properties of Thallium (III) oxide (Tl2O3) have been studied both experimentally and theoretically under compression at room temperature. X-ray powder diffraction measurements up to 37.7 GPa have been complemented with ab initio total-energy calculations. The equation of state of Tl2O3 has been determined and compared to related compounds. It has been found experimentally that Tl2O3 remains in its initial cubic bixbyite-type structure up to 22.0 GPa. At this pressure, the onset of amorphization is observed, being the sample fully amorphous at 25.2 GPa. The sample retains the amorphous state after pressure release. To understand the pressure-induced amorphization process, we have studied theoretically the possible high-pressure phases of Tl2O3. Although a phase transition is theoretically predicted at 5.8 GPa to the orthorhombic Rh2O3-II-type structure and at 24.2 GPa to the orthorhombic alpha-Gd2S3-type structure, neither of these phases were observed experimentally, probably due to the hindrance of the pressure-driven phase transitions at room temperature. The theoretical study of the elastic behavior of the cubic bixbyite-type structure at high-pressure shows that amorphization above 22 GPa at room temperature might be caused by the mechanical instability of the cubic bixbyite-type structure which is theoretically predicted above 23.5 GPa. (C) 2014 AIP Publishing LLC. ; This study was supported by the Spanish government MEC under Grant Nos. MAT2010-21270-C04-01/03/04, MAT2013-46649-C4-1/2/3-P, and CTQ2009-14596-C02-01, by the Comunidad de Madrid and European Social Fund (S2009/PPQ-1551 4161893), by MALTA Consolider Ingenio 2010 project (CSD2007-00045), and by Generalitat Valenciana (GVA-ACOMP-2013-1012 and GVA-ACOMP-2014-243). We acknowledge Diamond Light Source for time on beamline I15 under proposal EE6517 and I15 beamline scientist for technical support. A.M. and P.R.-H. acknowledge computing time provided by Red Espanola de Supercomputacion (RES) and MALTA-Cluster. B.G.-D. and J.A.S. ...