Nucleant layer effect on nanocolumnar ZnO films grown by electrodeposition

Different ZnO nanostructured films were electrochemically grown, using an aqueous solution based on ZnCl2, on three types of transparent conductive oxides grow on commercial ITO (In2O3:Sn)-covered glass substrates: (1) ZnO prepared by spin coating, (2) ZnO prepared by direct current magnetron sputtering, and (3) commercial ITO-covered glass substrates. Although thin, these primary oxide layers play an important role on the properties of the nanostructured films grown on top of them. Additionally, these primary oxide layers prevent direct hole combination when used in optoelectronic devices. Structural and optical characterizations were carried out by scanning electron microscopy, atomic force microscopy, and optical transmission spectroscopy. We show that the properties of the ZnO nanostructured films depend strongly on the type of primary oxide-covered substrate used. Previous studies on different electrodeposition methods for nucleation and growth are considered in the final discussion.Facultad de Ciencias Exacta

Nucleant layer effect on nanocolumnar ZnO films grown by electrodeposition

Different ZnO nanostructured films were electrochemically grown, using an aqueous solution based on ZnCl2, on three types of transparent conductive oxides grow on commercial ITO (In2O3:Sn)-covered glass substrates: (1) ZnO prepared by spin coating, (2) ZnO prepared by direct current magnetron sputtering, and (3) commercial ITO-covered glass substrates. Although thin, these primary oxide layers play an important role on the properties of the nanostructured films grown on top of them. Additionally, these primary oxide layers prevent direct hole combination when used in optoelectronic devices. Structural and optical characterizations were carried out by scanning electron microscopy, atomic force microscopy, and optical transmission spectroscopy. We show that the properties of the ZnO nanostructured films depend strongly on the type of primary oxide-covered substrate used. Previous studies on different electrodeposition methods for nucleation and growth are considered in the final discussion.Facultad de Ciencias Exacta

One body, many heads; the Cerberus of catalysis. A new multipurpose in-situ cell for XAS at ALBA

A new multi-purpose in-situ cell and its control system have been developed for synchrotron-based techniques as are X-Ray Absorption spectroscopy (XAS) and X-Ray Diffraction (XRD). The cell is made of a stainless steel body and three different exchangeable heads to tackle different scientific areas that include solid-gas catalysis, solidliquid catalysis and electrocatalysis. The different versions of the cell are herein described and their functionality is exemplified by some case studies.Guilera, G.; Rey Garcia, F.; Hernandez Fenollosa, J.; Cortés Vergaz, JJ. (2013). One body, many heads; the Cerberus of catalysis. A new multipurpose in-situ cell for XAS at ALBA. Journal of Physics: Conference Series. 430:12057-12061. doi:10.1088/1742-6596/430/1/012057S120571206143

A standard protocol to report discrete stage-structured demographic information

Stage-based demographic methods, such as matrix population models (MPMs), are powerful tools used to address a broad range of fundamental questions in ecology, evolutionary biology and conservation science. Accordingly, MPMs now exist for over 3000 species worldwide. These data are being digitised as an ongoing process and periodically released into two large open-access online repositories: the COMPADRE Plant Matrix Database and the COMADRE Animal Matrix Database. During the last decade, data archiving and curation of COMPADRE and COMADRE, and subsequent comparative research, have revealed pronounced variation in how MPMs are parameterized and reported. Here, we summarise current issues related to the parameterisation and reporting of MPMs that arise most frequently and outline how they affect MPM construction, analysis, and interpretation. To quantify variation in how MPMs are reported, we present results from a survey identifying key aspects of MPMs that are frequently unreported in manuscripts. We then screen COMPADRE and COMADRE to quantify how often key pieces of information are omitted from manuscripts using MPMs. Over 80% of surveyed researchers (n = 60) state a clear benefit to adopting more standardised methodologies for reporting MPMs. Furthermore, over 85% of the 300 MPMs assessed from COMPADRE and COMADRE omitted one or more elements that are key to their accurate interpretation. Based on these insights, we identify fundamental issues that can arise from MPM construction and communication and provide suggestions to improve clarity, reproducibility and future research utilising MPMs and their required metadata. To fortify reproducibility and empower researchers to take full advantage of their demographic data, we introduce a standardised protocol to present MPMs in publications. This standard is linked to www.compa dre-db.org, so that authors wishing to archive their MPMs can do so prior to submission of publications, following examples from other open-access repositories such as DRYAD, Figshare and Zenodo. Combining and standardising MPMs parameterized from populations around the globe and across the tree of life opens up powerful research opportunities in evolutionary biology, ecology and conservation research. However, this potential can only be fully realised by adopting standardised methods to ensure reproducibility

Nucleant layer effect on nanocolumnar ZnO films grown by electrodeposition

Different ZnO nanostructured films were electrochemically grown, using an aqueous solution based on ZnCl2, on three types of transparent conductive oxides grow on commercial ITO (In2O3:Sn)-covered glass substrates: (1) ZnO prepared by spin coating, (2) ZnO prepared by direct current magnetron sputtering, and (3) commercial ITO-covered glass substrates. Although thin, these primary oxide layers play an important role on the properties of the nanostructured films grown on top of them. Additionally, these primary oxide layers prevent direct hole combination when used in optoelectronic devices. Structural and optical characterizations were carried out by scanning electron microscopy, atomic force microscopy, and optical transmission spectroscopy. We show that the properties of the ZnO nanostructured films depend strongly on the type of primary oxide-covered substrate used. Previous studies on different electrodeposition methods for nucleation and growth are considered in the final discussion.We thank Prof. A. Segura of the Universitat de Valencia for the facilities with the sputtering equipment. This work was supported by the project PROMETEO/2009/074 from the Generalitat Valenciana.Reyes Tolosa, MD.; Damonte, LC.; Brine, H.; Bolink, HJ.; Hernández Fenollosa, MDLÁ. (2013). Nucleant layer effect on nanocolumnar ZnO films grown by electrodeposition. Nanoscale Research Letters. 8:135-144. https://doi.org/10.1186/1556-276X-8-135S1351448Franklin JB, Zou B, Petrov P, McComb DW, Ryanand MP, McLachlan MA,J: Optimised pulsed laser deposition of ZnO thin films on transparent conducting substrates. Mater Chem 2011, 21: 8178–8182. 10.1039/c1jm10658aJaroslav B, Andrej V, Marie N, Šuttab P, Miroslav M, František U: Cryogenic pulsed laser deposition of ZnO. Vacuum 2012, 86(6):684–688. 10.1016/j.vacuum.2011.07.033Jae Bin L, Hyeong Joon K, Soo Gil K, Cheol Seong H, Seong-Hyeon H, Young Hwa S, Neung Hun L: Deposition of ZnO thin films by magnetron sputtering for a film bulk acoustic resonator. Thin Solid Films 2003, 435: 179–185. 10.1016/S0040-6090(03)00347-XXionga DP, Tanga XG, Zhaoa WR, Liua QX, Wanga YH, Zhoub SL: Deposition of ZnO and MgZnO films by magnetron sputtering. Vacuum 2013, 89: 254–256.Reyes Tolosa MD, Orozco-Messana J, Lima ANC, Camaratta R, Pascual M, Hernandez-Fenollosa MA: Electrochemical deposition mechanism for ZnO nanorods: diffusion coefficient and growth models. J Electrochem Soc 2011, 158(11):E107-E110.Ming F, Ji Z: Mechanism of the electrodeposition of ZnO nanosheets below room temperature. J Electrochem Soc 2010, 157(8):D450-D453. 10.1149/1.3447738Pullini D, Pruna A, Zanin S, Busquets Mataix D: High-efficiency electrodeposition of large scale ZnO nanorod arrays for thin transparent electrodes. J Electrochem Soc 2012, 159: E45-E51. 10.1149/2.093202jesPruna A, Pullini D, Busquets Mataix D: Influence of deposition potential on structure of ZnO nanowires synthesized in track-etched membranes. J Electrochem Soc 2012, 159: E92-E98. 10.1149/2.003205jesMarotti RE, Giorgi P, Machado G, Dalchiele EA: Crystallite size dependence of band gap energy for electrodeposited ZnO grown at different temperatures. Solar Energy Materials and Solar Cells 2009, 90(15):2356–2361.Yeong Hwan K, Myung Sub K, Jae Su Y: Structural and optical properties of ZnO nanorods by electrochemical growth using multi-walled carbon nanotube-composed seed layers. Nanoscale Res Lett 2012, 7: 13. 10.1186/1556-276X-7-13Elias J, Tena-Zaera R, Lévy-Clément C: Electrodeposition of ZnO nanowires with controlled dimensions for photovoltaic applications: role of buffer layer. Thin Solid Films 2007, 515(24):8553–8557. 10.1016/j.tsf.2007.04.027Zhai Y, Zhai S, Chen G, Zhang K, Yue Q, Wang L, Liu J, Jia J: Effects of morphology of nanostructured ZnO on direct electrochemistry and biosensing properties of glucose oxidase. J Electroanal Chem 2011, 656: 198–205. 10.1016/j.jelechem.2010.11.020Reyes Tolosa MD, Orozco-Messana J, Damonte LC, Hernandez-Fenollosa MA: ZnO nanoestructured layers processing with morphology control by pulsed electrodeposition. J Electrochem Soc 2011, 158(7):D452-D455. 10.1149/1.3593004Gouxa A, Pauporté T, Chivot J, Lincot D: Temperature effects on ZnO electrodeposition. Electrochim Acta 2005, 50(11):2239–2248. 10.1016/j.electacta.2004.10.007Kwok WM, Djurisic , Aleksandra B, Leung , Yu H, Li D, Tam KH, Phillips DL, Chan WK: Influence of annealing on stimulated emission in ZnO nanorods. Appl Phys Lett 2006, 89(18):183112. 183112–3 183112–3 10.1063/1.2378560Donderis V, Hernández-Fenollosa MA, Damonte LC, Marí B, Cembrero J: Enhancement of surface morphology and optical properties of nanocolumnar ZnO films. Superlattices and Microstructures 2007, 42: 461–467. 10.1016/j.spmi.2007.04.068Ghayour H, Rezaie HR, Mirdamadi S, Nourbakhsh AA: The effect of seed layer thickness on alignment and morphology of ZnO nanorods. Vacuum 2011, 86: 101–105. 10.1016/j.vacuum.2011.04.025Michael B, Mohammad Bagher R, Sayyed-Hossein K, Wojtek W, Kourosh K-z: Aqueous synthesis of interconnected ZnO nanowires using spray pyrolysis deposited seed layers. Mater Lett 2010, 64: 291–294. 10.1016/j.matlet.2009.10.065Jang Bo S, Hyuk C, Sung-O K: Rapid hydrothermal synthesis of zinc oxide nanowires by annealing methods on seed layers. J Nanomater 2011, 2011: 6.Peiro AM, Punniamoorthy R, Kuveshni G, Boyle DS, Paul O’B, Donal DC, Bradley , Jenny N, Durrant JR: Hybrid polymer/metal oxide solar cells based on ZnO columnar structures. J Mater Chem 2006, 16(21):2088–2096. 10.1039/b602084dVallet-Regí M, Salinas AJ, Arcos D: From the bioactive glasses to the star gels. J Mater Sci Mater Med 2006, 17: 1011–1017.Peulon S, Lincot D: Mechanistic study of cathodic electrodeposition of zinc oxide and zinc hydroxychloride films from oxygenated aqueous zinc chloride solutions. J Electrochem Soc 1998, 145: 864. 10.1149/1.1838359Dalchiele EA, Giorgi P, Marotti RE, Martín F, Ramos-Barrado JR, Ayouci R, Leinen D: Electrodeposition of ZnO thin films on n-Si(100). Sol. Energy Mater. Sol. Cells 2001, 70: 245. 10.1016/S0927-0248(01)00065-4Courtney IA, Dahn JR: Electrochemical and in situ X‐ray diffraction studies of the reaction of lithium with tin oxide composites. J Electrochem Soc 1997, 144(6):2045–2052. 10.1149/1.183774

A standard protocol to report discrete stage‐structured demographic information

Stage-based demographic methods, such as matrix population models (MPMs), are powerful tools used to address a broad range of fundamental questions in ecology, evolutionary biology and conservation science. Accordingly, MPMs now exist for over 3000 species worldwide. These data are being digitised as an ongoing process and periodically released into two large open-access online repositories: the COMPADRE Plant Matrix Database and the COMADRE Animal Matrix Database. During the last decade, data archiving and curation of COMPADRE and COMADRE, and subsequent comparative research, have revealed pronounced variation in how MPMs are parameterized and reported. Here, we summarise current issues related to the parameterisation and reporting of MPMs that arise most frequently and outline how they affect MPM construction, analysis, and interpretation. To quantify variation in how MPMs are reported, we present results from a survey identifying key aspects of MPMs that are frequently unreported in manuscripts. We then screen COMPADRE and COMADRE to quantify how often key pieces of information are omitted from manuscripts using MPMs. Over 80% of surveyed researchers (n = 60) state a clear benefit to adopting more standardised methodologies for reporting MPMs. Furthermore, over 85% of the 300 MPMs assessed from COMPADRE and COMADRE omitted one or more elements that are key to their accurate interpretation. Based on these insights, we identify fundamental issues that can arise from MPM construction and communication and provide suggestions to improve clarity, reproducibility and future research utilising MPMs and their required metadata. To fortify reproducibility and empower researchers to take full advantage of their demographic data, we introduce a standardised protocol to present MPMs in publications. This standard is linked to www.compadre-db.org, so that authors wishing to archive their MPMs can do so prior to submission of publications, following examples from other open-access repositories such as DRYAD, Figshare and Zenodo. Combining and standardising MPMs parameterized from populations around the globe and across the tree of life opens up powerful research opportunities in evolutionary biology, ecology and conservation research. However, this potential can only be fully realised by adopting standardised methods to ensure reproducibility

A standard protocol to report discrete stage-structured demographic information

Stage-based demographic methods, such as matrix population models (MPMs), are powerful tools used to address a broad range of fundamental questions in ecology, evolutionary biology and conservation science. Accordingly, MPMs now exist for over 3000 species worldwide. These data are being digitised as an ongoing process and periodically released into two large open-access online repositories: the COMPADRE Plant Matrix Database and the COMADRE Animal Matrix Database. During the last decade, data archiving and curation of COMPADRE and COMADRE, and subsequent comparative research, have revealed pronounced variation in how MPMs are parameterized and reported. Here, we summarise current issues related to the parameterisation and reporting of MPMs that arise most frequently and outline how they affect MPM construction, analysis, and interpretation. To quantify variation in how MPMs are reported, we present results from a survey identifying key aspects of MPMs that are frequently unreported in manuscripts. We then screen COMPADRE and COMADRE to quantify how often key pieces of information are omitted from manuscripts using MPMs. Over 80% of surveyed researchers (n = 60) state a clear benefit to adopting more standardised methodologies for reporting MPMs. Furthermore, over 85% of the 300 MPMs assessed from COMPADRE and COMADRE omitted one or more elements that are key to their accurate interpretation. Based on these insights, we identify fundamental issues that can arise from MPM construction and communication and provide suggestions to improve clarity, reproducibility and future research utilising MPMs and their required metadata. To fortify reproducibility and empower researchers to take full advantage of their demographic data, we introduce a standardised protocol to present MPMs in publications. This standard is linked to www.compadre-db.org, so that authors wishing to archive their MPMs can do so prior to submission of publications, following examples from other open-access repositories such as DRYAD, Figshare and Zenodo. Combining and standardising MPMs parameterized from populations around the globe and across the tree of life opens up powerful research opportunities in evolutionary biology, ecology and conservation research. However, this potential can only be fully realised by adopting standardised methods to ensure reproducibility

ITO Top-Electrodes via Industrial-Scale PLD for Efficient Buffer-Layer-Free Semitransparent Perovskite Solar Cells

The deposition of transparent conductive oxides (TCO) usually employs harsh conditions that are frequently harmful to soft/organic underlayers. Herein, successful use of an industrial pulsed laser deposition (PLD) tool to directly deposit indium tin oxide (ITO) films on semitransparent vacuum-deposited perovskite solar cells without damage to the device stack is demonstrated. The morphological, electronic, and optical properties of the PLD deposited ITO films are optimized. A direct relation between the PLD chamber pressure and the solar cell performance is obtained. The semitransparent perovskite solar cells prepared exclusively by vacuum-assisted techniques had fill factors of 78% and exceeded 18% in power conversion efficiencies. This demonstrates that the direct deposition of TCO-based top electrodes without protective buffer layers is possible and leads to efficient devices

Effect of N isotopic mass on the photoluminescence and cathodoluminescence spectra of gallium nitride

GaN is a wurtzite-type semiconductor at ambient conditions whose natural composition consists of almost pure 14N (99.63% 14N and 0.37% 15N) and a mixture of 60.1% 69Ga, and 39.9% 71Ga. We report a low-temperature photoluminescence and cathodoluminescence study of GaN thin films made from natural Ga and N, and from natural Ga and isotopically pure 15N. The contribution of the nitrogen vibrations to the bandgap renormalization by electron-phonon interaction has been estimated from the nitrogen isotopic mass coefficient of the bound exciton energy. The temperature dependence of the bandgap of GaN can be explained with the measured isotopic mass coefficients of Ga and N. We have estimated the aluminum and indium contribution to the bandgap renormalization in AlN and InN from the temperature dependence of the AlN and InN bandgap up to 300 K, assuming that the N contribution is similar to that found in GaN. The similar bandgap isotopic mass coefficients of C, N, and O, of Al, Si and P, of Zn, Ga and Ge, and of Cd and In suggests that elements of the same row of the periodic table have similar bandgap isotopic mass coefficients