Publications

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Journal Article
Miguel, C., J. V. Pinto, M. Clarke, and M. J. Melo, "The alchemy of red mercury sulphide: The production of vermilion for medieval art", Dyes and Pigments, vol. 102, pp. 210-217, 2014. AbstractWebsite

Vermilion red, mercury sulphide (α-HgS), was one of the most important reds in art and its use as a pigment dates back to Antiquity. In medieval Europe, it could be mined as cinnabar, or produced as vermilion by heating mercury with sulphur. This work aims to study the production of synthetic vermilion as a medieval pigment and to confirm which was the source (mineral or artificial) of the reds used in Portuguese medieval illuminations. The production of synthetic vermilion was based on the process described in the Judaeo-Portuguese medieval treatise “The book on how to make colours”, using materials and technologies as close as possible to the medieval ones. The reaction mechanism was studied by following the heating process by X-ray diffraction, and it was possible to conclude that the transformation from black cubic β-HgS into red hexagonal α-HgS is a solid-state phase transition, occurring at 235 °C. This result is contrary to what published in technical art literature, in which this process is described as a sublimation. Moreover, Scanning Electron Microscopy evidenced a sinterization effect on the artificial vermilion, not found in medieval original samples nor in paints prepared with mineral cinnabar from Almadén (Spain). Red mercury sulphide, natural and synthetic, was then prepared as a parchment-glue paint and compared to proteinaceous red paints from 12th–13th century miniatures produced in important medieval monasteries, previously fully characterized by a multi-analytical approach (μ-Energy dispersive X-ray fluorescence, μ-Fourier Transform Infrared Spectroscopy, Raman microscopy). A comparative Electron probe microanalysis of the red paints point to a mineral provenance for medieval vermilion found in Portuguese illuminations.

Pinto, J. V., M. M. Cruz, R. C. da Silva, N. Franco, A. Casaca, E. Alves, and M. Godinho, "Anisotropic ferromagnetism induced in rutile single crystals by Co implantation", European Physical Journal B, vol. 55, issue 3, pp. 253-260, 2007. AbstractWebsite
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Casimiro, M. H., A. G. Silva, J. V. Pinto, A. M. Ramos, J. Vital, and L. M. Ferreira, "Catalytic poly(vinyl alcohol) functionalized membranes obtained by gamma irradiation", Radiation Physics and Chemistry, vol. 81, issue 9, pp. 1314-1318, 2012. Abstract
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Savoini, B., R. Gonzalez, J. V. Pinto, R. C. da Silva, and E. Alves, "Copper and cobalt nanocolloids in implanted MgO crystals", Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, vol. 257, pp. 563-567, 2007. AbstractWebsite
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Savoini, B., D. Caceres, R. Gonzalez, Y. Chen, J. V. Pinto, R. C. da Silva, and E. Alves, "Copper nanocolloids in MgO crystals implanted with Cu ions", Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, vol. 218, pp. 148-152, 2004. AbstractWebsite
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Nandy, S., G. Goncalves, J. V. Pinto, T. Busani, V. Figueiredo, L. Pereira, R. F. Paiva Martins, and E. Fortunato, "Current transport mechanism at metal-semiconductor nanoscale interfaces based on ultrahigh density arrays of p-type NiO nano-pillars", Nanoscale, vol. 5, issue 23, pp. 11699-11709, 2013. AbstractWebsite

The present work focuses on a qualitative analysis of localised I-V characteristics based on the nanostructure morphology of highly dense arrays of p-type NiO nano-pillars (NiO-NPs). Vertically aligned NiO-NPs have been grown on different substrates by using a glancing angle deposition (GLAD) technique. The preferred orientation of as grown NiO-NPs was controlled by the deposition pressure. The NiO-NPs displayed a polar surface with a microscopic dipole moment along the (111) plane (Tasker's type III). Consequently, the crystal plane dependent surface electron accumulation layer and the lattice disorder at the grain boundary interface showed a non-uniform current distribution throughout the sample surface, demonstrated by a conducting AFM technique (c-AFM). The variation in I-V for different points in a single current distribution grain (CD-grain) has been attributed to the variation of Schottky barrier height (SBH) at the metal-semiconductor (M-S) interface. Furthermore, we observed that the strain produced during the NiO-NPs growth can modulate the SBH. Inbound strain acts as an external field to influence the local electric field at the M-S interface causing a variation in SBH with the NPs orientation. This paper shows that vertical arrays of NiO-NPs are potential candidates for nanoscale devices because they have a great impact on the local current transport mechanism due to its nanostructure morphology.

Duarte, P., D. P. Ferreira, T. F. Lopes, J. V. Pinto, I. M. Fonseca, I. Ferreira Machado, and L. F. Vieira Ferreira, "DSM as a probe for the characterization of modified mesoporous silicas", Microporous and Mesoporous Materials, vol. 161, pp. 139-147, 2012. Abstract
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Tardio, M., R. Ramirez, R. Gonzalez, J. V. Pinto, R. C. da Silva, E. Alves, and Y. Chen, "Electrical conductivity of as-grown and oxidized MgO : Li crystals implanted with Li ions", Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, vol. 218, pp. 164-169, 2004. AbstractWebsite
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Pereira, S., A. Gonçalves, N. Correia, J. Pinto, L. Í. Pereira, R. Martins, and E. Fortunato, "Electrochromic behavior of NiO thin films deposited by e-beam evaporation at room temperature", Solar Energy Materials and Solar Cells, vol. 120, Part A, pp. 109-115, 2014. AbstractWebsite

In this work we report the role of thickness on electrochromic behavior of nickel oxide (NiO) films deposited by e-beam evaporation at room temperature on ITO-coated glass. The structure and morphology of films with thicknesses between 100 and 500 nm were analyzed and then correlated with electrochemical response and transmittance modulation when immersed in 0.5 M LiClO4–PC electrolyte. The NiO exhibits an anodic coloration, reaching for the thickest film a transmittance modulation of 66% between colored and bleached state, at 630 nm, with a color efficiency of 55 cm2 C−1. Very fast switch between states was obtained, where coloration and bleaching times are 3.6 s cm−2 and 1.4 s cm−2, respectively.

Raiola, F., P. Migliardi, G. Gyurky, M. Aliotta, A. Formicola, R. Bonetti, C. Broggini, L. Campajola, P. Corvisiero, H. Costantini, J. Cruz, A. D'Onofrio, Z. Fulop, G. Gervino, L. Gialanella, A. Guglielmetti, G. Imbriani, C. Gustavino, A. P. Jesus, M. Junker, R. W. Kavanagh, P. G. P. Moroni, A. Ordine, J. V. Pinto, P. Prati, V. Roca, J. P. Ribeiro, D. Rogalla, C. Rolfs, M. Romano, F. Schumann, D. Schurmann, E. Somorjai, F. Strieder, F. Terrasi, H. P. Trautvetter, and S. Zavatarelli, "Enhanced electron screening in d(d, p)t for deuterated Ta", European Physical Journal A, vol. 13, issue 3, pp. 377-382, 2002. AbstractWebsite
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Nayak, P. K., J. V. Pinto, G. Goncalves, R. Martins, and E. Fortunato, "Environmental, Optical, and Electrical Stability Study of Solution-Processed Zinc-Tin-Oxide Thin-Film Transistors", Journal of Display Technology, vol. 7, issue 12, pp. 640-643, 2011. Abstract
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Ribeiro, J. P., A. P. Jesus, B. Braizinha, J. Cruz, R. Mateus, and J. V. Pinto, "Experimental study of the F-19(p,alpha gamma)O-16 reaction", Nuclear Physics A, vol. 688, issue 1-2, pp. 468C-471C, 2001. AbstractWebsite
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Pinto, J. V., R. Branquinho, P. Barquinha, E. Alves, R. Martins, and E. Fortunato, "Extended-Gate ISFETs Based on Sputtered Amorphous Oxides", Journal of Display Technology, vol. 9, issue 9, pp. 729-734, 2013. AbstractWebsite
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Borges, R. P., J. V. Pinto, R. C. da Silva, A. P. Goncalves, M. M. Cruz, and M. Godinho, "Ferromagnetism in ZnO doped with Co by ion implantation", Journal of Magnetism and Magnetic Materials, vol. 316, issue 2, pp. E191-E194, 2007. AbstractWebsite
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Casella, C., H. Costantini, A. Lemut, B. Limata, R. Bonetti, C. Broggini, L. Campajola, P. Corvisiero, J. Cruz, A. D'Onofrio, A. Formicola, Z. Fulop, G. Gervino, L. Gialanella, A. Guglielmetti, C. Gustavino, G. Gyurky, G. Imbriani, A. P. Jesus, M. Junker, A. Ordine, J. V. Pinto, P. Prati, J. P. Ribeiro, V. Roca, D. Rogalla, C. Rolfs, M. Romano, C. Rossi-Alvarez, F. Scheumann, E. Somorjai, O. Straniero, F. Strieder, F. Terrasi, H. P. Tratuvetter, S. Zavatarelli, and L. Collaboration, "First measurement of the d(p, gamma)He-3 cross section down to the solar Gamow peak", Nuclear Physics A, vol. 706, issue 1-2, pp. 203-216, 2002. AbstractWebsite
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Veigas, B., R. Branquinho, J. V. Pinto, P. J. Wojcik, R. Martins, E. Fortunato, and P. V. Baptista, "Ion sensing (EIS) real-time quantitative monitorization of isothermal DNA amplification", Biosensors and Bioelectronics, 2014. Abstract
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Cruz, M. M., R. C. da Silva, J. V. Pinto, R. G. Gonzalez, E. Alves, and M. Godinho, "Magnetic behavior of Co and Ni implanted MgO", Journal of Magnetism and Magnetic Materials, vol. 272, pp. 840-842, 2004. AbstractWebsite
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Pinto, J. V., M. M. Cruz, R. C. da Silva, E. Alves, R. Gonzalez, and M. Godinho, "Magnetic nanoscale aggregates of cobalt and nickel in MgO single crystals", European Physical Journal B, vol. 45, issue 3, pp. 331-338, 2005. AbstractWebsite
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Pinto, J. V., M. M. Cruz, R. C. da Silva, E. Alves, and M. Godinho, "Magnetic properties of TiO2 rutile implanted with Ni and Co", Journal of Magnetism and Magnetic Materials, vol. 294, issue 2, pp. E73-E76, 2005. AbstractWebsite
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Casella, C., H. Costantini, A. Lemut, B. Limata, D. Bemmerer, R. Bonetti, C. Broggini, L. Campajola, P. Cocconi, P. Corvisiero, J. Cruz, A. D'Onofrio, A. Formicola, Z. Fulop, G. Gervino, L. Gialanella, A. Guglielmetti, C. Gustavino, G. Gyurky, A. Loiano, G. Imbriani, A. P. Jesus, M. Junker, P. Musico, A. Ordine, F. Parodi, M. Parolin, J. V. Pinto, P. Prati, J. P. Ribeiro, V. Roca, D. Rogalla, C. Rolfs, M. Romano, C. Rossi-Alvarez, A. Rottura, F. Schuemann, E. Somorjai, F. Strieder, F. Terrasi, H. P. Trautvetter, A. Vomiero, and S. Zavatarelli, "A new setup for the underground study of capture reactions", Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, vol. 489, issue 1-3, pp. 160-169, 2002. AbstractWebsite
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Alves, E., J. V. Pinto, R. C. da Silva, M. Peres, M. J. Soares, and T. Monteiro, "Optical behaviour of Er doped rutile by ion implantation", Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, vol. 250, pp. 363-367, 2006. AbstractWebsite
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Figueiredo, V., J. V. Pinto, J. Deuermeier, R. Barros, E. Alves, R. Martins, and E. Fortunato, "p-Type CuxO Thin-Film Transistors Produced by Thermal Oxidation", Journal of Display Technology, vol. 9, issue 9, pp. 6, 2013. AbstractWebsite
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Nunes, D., A. Pimentel, J. V. Pinto, T. R. Calmeiro, S. Nandy, P. Barquinha, L. Pereira, P. A. Carvalho, E. Fortunato, and R. Martins, "Photocatalytic behavior of TiO2 films synthesized by microwave irradiation", Catalysis Today, 2015. AbstractWebsite

Titanium dioxide was synthesized on glass substrates from titanium (IV)isopropoxide and hydrochloride acid aqueous solutions through microwave irradiation using as seed layer either fluorine-doped crystalline tin oxide (SnO2:F) or amorphous tin oxide (a-SnOx). Three routes have been followed with distinct outcome: (i) equimolar hydrochloride acid/water proportions (1HCl:1water) resulted in nanorod arrays for both seed layers; (ii) higher water proportion (1HCl:3water) originated denser films with growth yield dependent on the seed layer employed; while (iii) higher acid proportion (3HCl:1water) hindered the formation of TiO2. X-ray diffraction (XRD) showed that the materials crystallized with the rutile structure, possibly with minute fractions of brookite and/or anatase. XRD peak inversions observed for the materials synthesized on crystalline seeds pointed to preferred crystallographic orientation. Electron diffraction showed that the especially strong XRD peak inversions observed for TiO2 grown from the 1HCl:3water solution on SnO2:F originated from a [001] fiber texture. Transmittance spectrophotometry showed that the materials with finer structure exhibited significantly higher optical band gaps. Photocatalytic activity was assessed from methylene blue degradation, with the 1HCl:3water SnO2:F material showing remarkable degradability performance, attributed to a higher exposure of (001) facets, together with stability and reusability.

Branquinho, R., J. V. Pinto, T. Busani, P. Barquinha, L. Pereira, P. Viana Baptista, R. Martins, and E. Fortunato, "Plastic Compatible Sputtered Ta2O5 Sensitive Layer for Oxide Semiconductor TFT Sensors", Display Technology, Journal of, vol. 9, issue 9, pp. 723-728, 2013. Abstract

The effect of post-deposition annealing temperature on the pH sensitivity of room temperature RF sputtered Ta2O5 was investigated. Structural and morphological features of these films were analyzed before and after annealing at various temperatures. The deposited films are amorphous up to 600 °C and crystallize at 700 °C in an orthorhombic phase. Electrolyte-insulator-semiconductor (EIS) field effect based sensors with an amorphous Ta2O5 sensing layer showed pH sensitivity above 50 mV/pH. For sensors annealed above 200 °C pH sensitivity decreased with increasing temperature. Stabilized sensor response and maximum pH sensitivity was achieved after low temperature annealing at 200 °C, which is compatible with the use of polymeric substrates and application as sensitive layer in oxides TFT-based sensors.

Mateus, R., A. P. Jesus, B. Braizinha, J. Cruz, J. V. Pinto, and J. P. Ribeiro, "Proton-induced gamma-ray analysis of lithium in thick samples", Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, vol. 190, pp. 117-121, 2002. AbstractWebsite
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