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The valorization of spent oil bleaching earths (SOBE) is crucial for the protection of the environment and the reuse of resources. In this research, alkali-activated binders were manufactured at room temperature using SOBE as a precursor by varying the mass ratio between the activating solutions of sodium silicate (Na2SiO3) and 6 M sodium hydroxide (NaOH) (activating solution modulus) (Na2SiO3/NaOH ratio = 1/1; 1/2; 1/3; 1/4) to investigate the influence on the technological properties of the materials. This process intends to evaluate the potential of SOBE, heat-treated at 550 °C (1 h), as a precursor of the reaction (source of aluminosilicates). Samples produced with higher amounts of sodium silicate developed a denser structure, with lower porosity and a higher amount of geopolymer gel. Maximum flexural (8.35 MPa) and compressive (28.4 MPa) strengths of samples cured at room temperature for 28 days were obtained with a Na2SiO3/NaOH mass ratio of 1/1. The study demonstrates that SOBE waste can be used as a precursor in the manufacture of geopolymer binders that show a good compromise between physical, mechanical and thermally insulating characteristics.
P. Delgado-Plana; A. Rodríguez-Expósito; S. Bueno-Rodríguez; L. Pérez-Villarejo; D. Tobaldi; J. Labrincha; D. Eliche-Quesada. Effect of Activating Solution Modulus on the Synthesis of Sustainable Geopolymer Binders Using Spent Oil Bleaching Earths as Precursor. Sustainability 2021, 13, 7501 .
AMA StyleP. Delgado-Plana, A. Rodríguez-Expósito, S. Bueno-Rodríguez, L. Pérez-Villarejo, D. Tobaldi, J. Labrincha, D. Eliche-Quesada. Effect of Activating Solution Modulus on the Synthesis of Sustainable Geopolymer Binders Using Spent Oil Bleaching Earths as Precursor. Sustainability. 2021; 13 (13):7501.
Chicago/Turabian StyleP. Delgado-Plana; A. Rodríguez-Expósito; S. Bueno-Rodríguez; L. Pérez-Villarejo; D. Tobaldi; J. Labrincha; D. Eliche-Quesada. 2021. "Effect of Activating Solution Modulus on the Synthesis of Sustainable Geopolymer Binders Using Spent Oil Bleaching Earths as Precursor." Sustainability 13, no. 13: 7501.
Hierarchically porous hydroxyapatite derived from cork powder shows excellent performance in biomedicine (low cytotoxicity) and environmental remediation (high Pb2+ removal).
Francesca Scalera; Alessandra Quarta; David M. Tobaldi; Robert C. Pullar; Clara Piccirillo. Cork-derived hierarchically porous hydroxyapatite with different stoichiometries for biomedical and environmental applications. Materials Chemistry Frontiers 2021, 5, 5071 -5081.
AMA StyleFrancesca Scalera, Alessandra Quarta, David M. Tobaldi, Robert C. Pullar, Clara Piccirillo. Cork-derived hierarchically porous hydroxyapatite with different stoichiometries for biomedical and environmental applications. Materials Chemistry Frontiers. 2021; 5 (13):5071-5081.
Chicago/Turabian StyleFrancesca Scalera; Alessandra Quarta; David M. Tobaldi; Robert C. Pullar; Clara Piccirillo. 2021. "Cork-derived hierarchically porous hydroxyapatite with different stoichiometries for biomedical and environmental applications." Materials Chemistry Frontiers 5, no. 13: 5071-5081.
This article reports a novel photocatalytic lime render for indoor and outdoor air quality improvement that is composed of a lime binder and doped TiO2 (KRONOClean 7000®) nanoparticles. These nanoparticles were distributed throughout the bulk of the finishing render, instead of as a thin coating, thus ensuring the durability of the photocatalytic properties upon superficial damage. The physical properties of these renders were not affected by the addition of nanoparticles except in the case of surface area, which increased significantly. In terms of their photocatalytic activity, these novel lime renders were shown to degrade up to 12% NOx under UV light and up to 11% formaldehyde under visible light.
José Ibáñez Gómez; Andrea Giampiccolo; David Tobaldi; Sabine Mair; Carla da Silva; Maria Barrasa; Daniel Maskell; Martin Ansell; Rajnish Kurchania; Florian Mayer; Joao Labrincha; Yolanda de Miguel; Richard Ball. Photocatalytic Lime Render for Indoor and Outdoor Air Quality Improvement. Catalysts 2021, 11, 296 .
AMA StyleJosé Ibáñez Gómez, Andrea Giampiccolo, David Tobaldi, Sabine Mair, Carla da Silva, Maria Barrasa, Daniel Maskell, Martin Ansell, Rajnish Kurchania, Florian Mayer, Joao Labrincha, Yolanda de Miguel, Richard Ball. Photocatalytic Lime Render for Indoor and Outdoor Air Quality Improvement. Catalysts. 2021; 11 (3):296.
Chicago/Turabian StyleJosé Ibáñez Gómez; Andrea Giampiccolo; David Tobaldi; Sabine Mair; Carla da Silva; Maria Barrasa; Daniel Maskell; Martin Ansell; Rajnish Kurchania; Florian Mayer; Joao Labrincha; Yolanda de Miguel; Richard Ball. 2021. "Photocatalytic Lime Render for Indoor and Outdoor Air Quality Improvement." Catalysts 11, no. 3: 296.
In the present study, two photocatalytic graphene oxide (GO) and carbon nanotubes (CNT) modified TiO2 materials thermally treated at 300 °C (T300_GO and T300_CNT, respectively) were tested and revealed their conversion efficiency of nitrogen oxides (NOx) under simulated solar light, showing slightly better results when compared with the commercial Degussa P25 material at the initial concentration of NOx of 200 ppb. A chemical kinetic model based on the Langmuir–Hinshelwood (L-H) mechanism was employed to simulate micropollutant abatement. Modeling of the fluid dynamics and photocatalytic oxidation (PCO) kinetics was accomplished with computational fluid dynamics (CFD) approach for modeling single-phase liquid fluid flow (air/NOx mixture) with an isothermal heterogeneous surface reaction. A tuning methodology based on an extensive CFD simulation procedure was applied to adjust the kinetic model parameters toward a better correspondence between simulated and experimentally obtained data. The kinetic simulations of heterogeneous photo-oxidation of NOx carried out with the optimized parameters demonstrated a high degree of matching with the experimentally obtained NOx conversion. T300_CNT is the most active photolytic material with a degradation rate of 62.1%, followed by P25-61.4% and T300_GO-60.4%, when irradiated, for 30 min, with emission spectra similar to solar light.
Tatiana Zhiltsova.; Nelson Martins; Mariana R. F. Silva; Carla F. Da Silva; Mirtha A. O. Lourenço; David M. Tobaldi; Daniel Covita; Maria Paula Seabra; Paula Ferreira. Experimental and Computational Analysis of NOx Photocatalytic Abatement Using Carbon-Modified TiO2 Materials. Catalysts 2020, 10, 1366 .
AMA StyleTatiana Zhiltsova., Nelson Martins, Mariana R. F. Silva, Carla F. Da Silva, Mirtha A. O. Lourenço, David M. Tobaldi, Daniel Covita, Maria Paula Seabra, Paula Ferreira. Experimental and Computational Analysis of NOx Photocatalytic Abatement Using Carbon-Modified TiO2 Materials. Catalysts. 2020; 10 (12):1366.
Chicago/Turabian StyleTatiana Zhiltsova.; Nelson Martins; Mariana R. F. Silva; Carla F. Da Silva; Mirtha A. O. Lourenço; David M. Tobaldi; Daniel Covita; Maria Paula Seabra; Paula Ferreira. 2020. "Experimental and Computational Analysis of NOx Photocatalytic Abatement Using Carbon-Modified TiO2 Materials." Catalysts 10, no. 12: 1366.
Nanostructured thin films are widely investigated for application in multifunctional devices thanks to their peculiar optoelectronic properties. In this work anatase TiO2 nanoparticles (average diameter 10 nm) synthesised by a green aqueous sol-gel route are exploited to fabricate optically active electrodes for pseudocapacitive-electrochromic devices. In our approach, highly transparent and homogeneous thin films having a good electronic coupling between nanoparticles are prepared. These electrodes present a spongy-like nanostructure in which the dimension of native nanoparticles is preserved, resulting in a huge surface area. Cyclic voltammetry studies reveal that there are significant contributions to the total stored charge from both intercalation capacitance and pseudocapacitance, with a remarkable 50% of the total charge deriving from this second effect. Fast and reversible colouration occurs, with an optical modulation of ∼60% in the range of 315-1660 nm, and a colouration efficiency of 25.1 cm2 C-1 at 550 nm. This combination of pseudocapacitance and electrochromism makes the sol-gel derived titania thin films promising candidates for multifunctional 'smart windows'.
Roberto Giannuzzi; Tania Prontera; David M Tobaldi; Marco Pugliese; Luisa De Marco; Sonia Carallo; Giuseppe Gigli; Robert C Pullar; Vincenzo Maiorano. Pseudocapacitive behaviour in sol-gel derived electrochromic titania nanostructures. Nanotechnology 2020, 32, 045703 .
AMA StyleRoberto Giannuzzi, Tania Prontera, David M Tobaldi, Marco Pugliese, Luisa De Marco, Sonia Carallo, Giuseppe Gigli, Robert C Pullar, Vincenzo Maiorano. Pseudocapacitive behaviour in sol-gel derived electrochromic titania nanostructures. Nanotechnology. 2020; 32 (4):045703.
Chicago/Turabian StyleRoberto Giannuzzi; Tania Prontera; David M Tobaldi; Marco Pugliese; Luisa De Marco; Sonia Carallo; Giuseppe Gigli; Robert C Pullar; Vincenzo Maiorano. 2020. "Pseudocapacitive behaviour in sol-gel derived electrochromic titania nanostructures." Nanotechnology 32, no. 4: 045703.
The stability and reproducibility of the electric properties in n-type doped ZnO represent known bottlenecks towards potential thermoelectric applications. The degradation is promoted by the vanishing of the electronic defects on oxidation and irreversible exsolution of the phase impurities. This work proposes a microstructural mechanism showing that these processes take place mainly in the pores and highlighting the necessity for high densification of ZnO-based thermoelectrics to ensure more stable operation. The electrical performance was monitored at various temperatures, followed by a detailed microstructural analysis. The evolution of the electrical conductivity and Seebeck coefficient confirm that the degradation is related to a gradual decrease in the charge carrier concentration rather than to the effects suppressing their mobility. The results suggest that the donor exsolution may promote an increase or decrease of the power factor, guided by the self-optimization of the charge carrier concentration.
Blanca I. Arias-Serrano; Sergey M. Mikhalev; Marta C. Ferro; David M. Tobaldi; Jorge R. Frade; Andrei V. Kovalevsky. On the high-temperature degradation mechanism of ZnO-based thermoelectrics. Journal of the European Ceramic Society 2020, 41, 1730 -1734.
AMA StyleBlanca I. Arias-Serrano, Sergey M. Mikhalev, Marta C. Ferro, David M. Tobaldi, Jorge R. Frade, Andrei V. Kovalevsky. On the high-temperature degradation mechanism of ZnO-based thermoelectrics. Journal of the European Ceramic Society. 2020; 41 (2):1730-1734.
Chicago/Turabian StyleBlanca I. Arias-Serrano; Sergey M. Mikhalev; Marta C. Ferro; David M. Tobaldi; Jorge R. Frade; Andrei V. Kovalevsky. 2020. "On the high-temperature degradation mechanism of ZnO-based thermoelectrics." Journal of the European Ceramic Society 41, no. 2: 1730-1734.
Outdoor and indoor air pollution has become a global concern in modern society. Although many policies and regulations on air quality have been promulgated worldwide over the past decades, airborne pollution still negatively affects health and therefore the life-style of human beings. One of the strategies to challenge this problem might be reducing the amount of airborne pollutant by mineralising them via photoinduced reactions. Photocatalytic oxidation of gaseous pollutants via titanium dioxide is one of the most promising solar photochemical reactions. In this research work, by means of a green sol-gel procedure, we have coupled titania to graphene (0.5 and 1.0 wt%) aiming to increase the solar photocatalytic activity of the produced hybrid materials. Transient paramagnetic species formed upon UV-A irradiation were detected by means of EPR spectroscopy. The photocatalytic reactions were assessed by monitoring the removal of nitrogen oxides and two different volatile organic compounds (benzene and isopropanol), which has never been assessed before. Our results highlight the exceptional characteristics of the TiO2/graphene hybrid material synthesised with 1.0 wt% graphene, and its excellent suitability for multi-purpose applications in the field of environmental remediation. Compared to unmodified titania, it shows a clear enhancement in the photocatalytic removal of those hazardous pollutants, having a photocatalytic degradation rate twice higher. In addition, the same material is highly stable and shows fully recyclability over repeated tests. Hybrid titania-graphene materials could thus be exploited to grant safer outdoor and indoor environments, having thus a beneficial impact on public health and on the quality of our lives.
D.M. Tobaldi; D. Dvoranová; Luc Lajaunie; N. Rozman; B. Figueiredo; M.P. Seabra; A. Sever Škapin; J.J. Calvino; V. Brezová; J.A. Labrincha. Graphene-TiO2 hybrids for photocatalytic aided removal of VOCs and nitrogen oxides from outdoor environment. Chemical Engineering Journal 2020, 405, 126651 -126651.
AMA StyleD.M. Tobaldi, D. Dvoranová, Luc Lajaunie, N. Rozman, B. Figueiredo, M.P. Seabra, A. Sever Škapin, J.J. Calvino, V. Brezová, J.A. Labrincha. Graphene-TiO2 hybrids for photocatalytic aided removal of VOCs and nitrogen oxides from outdoor environment. Chemical Engineering Journal. 2020; 405 ():126651-126651.
Chicago/Turabian StyleD.M. Tobaldi; D. Dvoranová; Luc Lajaunie; N. Rozman; B. Figueiredo; M.P. Seabra; A. Sever Škapin; J.J. Calvino; V. Brezová; J.A. Labrincha. 2020. "Graphene-TiO2 hybrids for photocatalytic aided removal of VOCs and nitrogen oxides from outdoor environment." Chemical Engineering Journal 405, no. : 126651-126651.
Construction is recognized as one of the most polluting and energy consuming industries worldwide, especially in developing countries. Therefore, Research and Development (R&D) of novel manufacturing technologies and green construction materials is becoming extremely compelling. This study aims at evaluating the reuse of various wastes, originated in the Kraft pulp-paper industry, as raw materials in the manufacture of novel geopolymeric (GP) mortars whose properties fundamentally depend on the target application (e.g., insulating panel, partition wall, structural element, furnishing, etc.). Five different wastes were reused as filler: Two typologies of Biomass Fly Ash, calcareous sludge, grits, and dregs. The produced samples were characterized and a multi criteria analysis, able to take into account not only the engineering properties, but also the environmental and economic aspects, has been implemented. The criteria weights were evaluated using the Delphi methodology. The fuzzy Topsis approach has been used to consider the intrinsic uncertainty related to unconventional materials, as the produced GP-mortars. The computational analysis showed that adding the considered industrial wastes as filler is strongly recommended to improve the performance of materials intended for structural applications in construction. The results revealed that the formulations containing 5 wt.% of calcareous sludge, grits, and dregs and the one containing 7.5 wt.% of calcareous sludge, grits, dregs, and Biomass Fly Ash-1 have emerged as the best alternatives. Furthermore, it resulted that the Biomass Fly Ash-2 negatively influences the structural performance and relative rank of the material. Finally, this case study clearly shows that the fuzzy Topsis multi-criteria analysis represents a valuable and easy tool to investigate construction materials (either traditional and unconventional) when an intrinsic uncertainty is related to the measurement of the quantitative and qualitative characteristics.
Manfredi Saeli; Rosa Micale; Maria Paula Seabra; João A. Labrincha; Giada La Scalia. Selection of Novel Geopolymeric Mortars for Sustainable Construction Applications Using Fuzzy Topsis Approach. Sustainability 2020, 12, 5987 .
AMA StyleManfredi Saeli, Rosa Micale, Maria Paula Seabra, João A. Labrincha, Giada La Scalia. Selection of Novel Geopolymeric Mortars for Sustainable Construction Applications Using Fuzzy Topsis Approach. Sustainability. 2020; 12 (15):5987.
Chicago/Turabian StyleManfredi Saeli; Rosa Micale; Maria Paula Seabra; João A. Labrincha; Giada La Scalia. 2020. "Selection of Novel Geopolymeric Mortars for Sustainable Construction Applications Using Fuzzy Topsis Approach." Sustainability 12, no. 15: 5987.
Nanostructured systems showing reversible color switching are envisaged to play a significant role in photo-switches, photo-optical sensors, smart windows, displays, optical storage memories. Most of the materials exhibiting reversible color switching are organic molecules. However, their UV-light activation, low thermal and chemical stability, as well as harmful synthesis methods, limit their extensive use. In this research, we have created an inorganic switchable photochromic material exploiting TiO2 ability of creating an exciton upon excitation, copper as the chromophore, and graphene's extraordinarily high electron mobility. Spatially-resolved electron energy-loss spectroscopy and aberration-corrected transmission electron microscopy imaging highlight the high sp2 content of the graphene flakes as well as the presence of few-layers nanocage graphene decorating the surface of the flakes. Our material showed itself to be able to work under visible-light, its photochromic property being three times faster than conventional titania based photochromic materials, reaching a stable change in coloration after only 30 min of visible-light irradiation (vs. > 120 min in conventional Cu–TiO2). With the addition of just 1 wt% graphene, the material exhibited a staggeringly stable photochromic switching over repeated cycles. These results relate to the best previously reported values for any form of TiO2-based photochromic material. This is therefore an excellent candidate for smart-windows, light-sensitive information and energy storage devices, and other chromic devices and applications.
D.M. Tobaldi; L. Lajaunie; D. Dvoranová; V. Brezová; B. Figueiredo; M.P. Seabra; J.J. Calvino; J.A. Labrincha. Cooperative and fully reversible color switching activation in hybrid graphene decorated nanocages and copper-TiO2 nanoparticles. Materials Today Energy 2020, 17, 100460 .
AMA StyleD.M. Tobaldi, L. Lajaunie, D. Dvoranová, V. Brezová, B. Figueiredo, M.P. Seabra, J.J. Calvino, J.A. Labrincha. Cooperative and fully reversible color switching activation in hybrid graphene decorated nanocages and copper-TiO2 nanoparticles. Materials Today Energy. 2020; 17 ():100460.
Chicago/Turabian StyleD.M. Tobaldi; L. Lajaunie; D. Dvoranová; V. Brezová; B. Figueiredo; M.P. Seabra; J.J. Calvino; J.A. Labrincha. 2020. "Cooperative and fully reversible color switching activation in hybrid graphene decorated nanocages and copper-TiO2 nanoparticles." Materials Today Energy 17, no. : 100460.
Outdoor and indoor air pollution is a global environmental concern in modern society. Although many policies and regulations on air quality have been promulgated worldwide over the past decades, airborne pollution still negatively affects health and therefore the life-style of human beings. One of the strategies to challenge this problem might be reducing the amount of airborne pollutant by mineralising them via photoinduced reactions. Photocatalytic oxidation of gaseous pollutants via titanium dioxide is one of the most investigated solar photochemical reactions. In this research work, by means of a green sol-gel procedure, we have coupled titania to graphene (0.5 and 1.0 wt%) aiming to increase the solar photocatalytic activity of the produced hybrid materials. The photocatalytic reactions were assessed by monitoring the removal of nitrogen oxides and two different volatile organic compounds (benzene and isopropanol). Photocatalytic mechanism was investigated by means of EPR spin trapping experiments.Our results highlight the exceptional characteristics of the TiO2/graphene hybrid material (1.0 wt% graphene), and its suitability for multi-purpose applications in the field of environmental remediation. Compared to unmodified titania, the hybrid material with 1.0 wt% graphene shows a clear enhancement in the photocatalytic removal of those hazardous pollutants – corresponding to more than twice the photocatalytic degradation rate. In addition, the same material is highly stable and shows fully recyclability over repeated tests. Hybrid titania-graphene materials could thus be exploited to grant a safer outdoor and indoor environments, having a beneficial impact on public health and thus on the quality of our lives.
David Maria Tobaldi; Dana Dvoranova; Luc Lajaunie; Nejc Rozman; Bruno Figueiredo; Maria Paula Seabra; Andrijana Sever Skapin; José Calvino; Vlasta Brezova; Joao Antonio Labrincha. Photocatalytic Aided Removal of Nitrogen Oxides and VOCs from Outdoor Environment: Graphene as a Highway for Electron Mobility in TiO2 Nanoparticles. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Dana Dvoranova, Luc Lajaunie, Nejc Rozman, Bruno Figueiredo, Maria Paula Seabra, Andrijana Sever Skapin, José Calvino, Vlasta Brezova, Joao Antonio Labrincha. Photocatalytic Aided Removal of Nitrogen Oxides and VOCs from Outdoor Environment: Graphene as a Highway for Electron Mobility in TiO2 Nanoparticles. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Dana Dvoranova; Luc Lajaunie; Nejc Rozman; Bruno Figueiredo; Maria Paula Seabra; Andrijana Sever Skapin; José Calvino; Vlasta Brezova; Joao Antonio Labrincha. 2020. "Photocatalytic Aided Removal of Nitrogen Oxides and VOCs from Outdoor Environment: Graphene as a Highway for Electron Mobility in TiO2 Nanoparticles." , no. : 1.
Outdoor and indoor air pollution is a global environmental concern in modern society. Although many policies and regulations on air quality have been promulgated worldwide over the past decades, airborne pollution still negatively affects health and therefore the life-style of human beings. One of the strategies to challenge this problem might be reducing the amount of airborne pollutant by mineralising them via photoinduced reactions. Photocatalytic oxidation of gaseous pollutants via titanium dioxide is one of the most investigated solar photochemical reactions. In this research work, by means of a green sol-gel procedure, we have coupled titania to graphene (0.5 and 1.0 wt%) aiming to increase the solar photocatalytic activity of the produced hybrid materials. The photocatalytic reactions were assessed by monitoring the removal of nitrogen oxides and two different volatile organic compounds (benzene and isopropanol). Photocatalytic mechanism was investigated by means of EPR spin trapping experiments.Our results highlight the exceptional characteristics of the TiO2/graphene hybrid material (1.0 wt% graphene), and its suitability for multi-purpose applications in the field of environmental remediation. Compared to unmodified titania, the hybrid material with 1.0 wt% graphene shows a clear enhancement in the photocatalytic removal of those hazardous pollutants – corresponding to more than twice the photocatalytic degradation rate. In addition, the same material is highly stable and shows fully recyclability over repeated tests. Hybrid titania-graphene materials could thus be exploited to grant a safer outdoor and indoor environments, having a beneficial impact on public health and thus on the quality of our lives.
David Maria Tobaldi; Dana Dvoranova; Luc Lajaunie; Nejc Rozman; Bruno Figueiredo; Maria Paula Seabra; Andrijana Sever Skapin; José Calvino; Vlasta Brezova; Joao Antonio Labrincha. Photocatalytic Aided Removal of Nitrogen Oxides and VOCs from Outdoor Environment: Graphene as a Highway for Electron Mobility in TiO2 Nanoparticles. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Dana Dvoranova, Luc Lajaunie, Nejc Rozman, Bruno Figueiredo, Maria Paula Seabra, Andrijana Sever Skapin, José Calvino, Vlasta Brezova, Joao Antonio Labrincha. Photocatalytic Aided Removal of Nitrogen Oxides and VOCs from Outdoor Environment: Graphene as a Highway for Electron Mobility in TiO2 Nanoparticles. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Dana Dvoranova; Luc Lajaunie; Nejc Rozman; Bruno Figueiredo; Maria Paula Seabra; Andrijana Sever Skapin; José Calvino; Vlasta Brezova; Joao Antonio Labrincha. 2020. "Photocatalytic Aided Removal of Nitrogen Oxides and VOCs from Outdoor Environment: Graphene as a Highway for Electron Mobility in TiO2 Nanoparticles." , no. : 1.
Glucose sensing is promoted by halogen lamp photo-activation in CuO–TiO2 heterojunctions.
David Maria Tobaldi; Claudia Espro; Salvatore Gianluca Leonardi; Luc Lajaunie; Maria Paula Seabra; José Juan Calvino; Silvia Marini; João António Labrincha; Giovanni Neri. Photo-electrochemical properties of CuO–TiO2 heterojunctions for glucose sensing. Journal of Materials Chemistry C 2020, 8, 9529 -9539.
AMA StyleDavid Maria Tobaldi, Claudia Espro, Salvatore Gianluca Leonardi, Luc Lajaunie, Maria Paula Seabra, José Juan Calvino, Silvia Marini, João António Labrincha, Giovanni Neri. Photo-electrochemical properties of CuO–TiO2 heterojunctions for glucose sensing. Journal of Materials Chemistry C. 2020; 8 (28):9529-9539.
Chicago/Turabian StyleDavid Maria Tobaldi; Claudia Espro; Salvatore Gianluca Leonardi; Luc Lajaunie; Maria Paula Seabra; José Juan Calvino; Silvia Marini; João António Labrincha; Giovanni Neri. 2020. "Photo-electrochemical properties of CuO–TiO2 heterojunctions for glucose sensing." Journal of Materials Chemistry C 8, no. 28: 9529-9539.
Indoor and outdoor air pollution remains a major health risk for human beings. Nitrogen oxides and volatile organic compounds are amongst the major pollutant found outdoor. Thus, actions to diminish such risks and to provide safer outdoor / indoor environment are required. In this research work, we have decorated the surface of TiO2 with noble-metal oxides (Ag and/or CuxO) to improve the photocatalytic performances (removal of nitrogen oxides and benzene) under simulated solar-light irradiation. By means of advanced X-ray methods it has been shown that noble metals did not enter the TiO2 crystal structure, although they retarded the anatase-to-rutile phase transition and crystal growth. Photocatalytic activity was assessed in the gas-solid phase, monitoring the degradation of NOx and benzene, using a lamp simulating the solar radiation. Results showed that TiO2 modified with an Ag:Cu molar ratio equal to 1:1 (with Ag+Cu = 0.5+0.5 mol% = 1 mol%), was that exhibiting best de-NOx and benzene removal performances.
David Maria Tobaldi; Luc Lajaunie; Maria Paula Seabra; Raul Arenal; Joao Antonio Labrincha. TiO2 Surface Hybridisation with Noble Metals (Ag and CuxO) for Solar De-NOx and VOC Removal. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Luc Lajaunie, Maria Paula Seabra, Raul Arenal, Joao Antonio Labrincha. TiO2 Surface Hybridisation with Noble Metals (Ag and CuxO) for Solar De-NOx and VOC Removal. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Luc Lajaunie; Maria Paula Seabra; Raul Arenal; Joao Antonio Labrincha. 2020. "TiO2 Surface Hybridisation with Noble Metals (Ag and CuxO) for Solar De-NOx and VOC Removal." , no. : 1.
Indoor and outdoor air pollution remains a major health risk for human beings. Nitrogen oxides and volatile organic compounds are amongst the major pollutant found outdoor. Thus, actions to diminish such risks and to provide safer outdoor / indoor environment are required. In this research work, we have decorated the surface of TiO2 with noble-metal oxides (Ag and/or CuxO) to improve the photocatalytic performances (removal of nitrogen oxides and benzene) under simulated solar-light irradiation. By means of advanced X-ray methods it has been shown that noble metals did not enter the TiO2 crystal structure, although they retarded the anatase-to-rutile phase transition and crystal growth. Photocatalytic activity was assessed in the gas-solid phase, monitoring the degradation of NOx and benzene, using a lamp simulating the solar radiation. Results showed that TiO2 modified with an Ag:Cu molar ratio equal to 1:1 (with Ag+Cu = 0.5+0.5 mol% = 1 mol%), was that exhibiting best de-NOx and benzene removal performances.
David Maria Tobaldi; Luc Lajaunie; Maria Paula Seabra; Raul Arenal; Joao Antonio Labrincha. TiO2 Surface Hybridisation with Noble Metals (Ag and CuxO) for Solar De-NOx and VOC Removal. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Luc Lajaunie, Maria Paula Seabra, Raul Arenal, Joao Antonio Labrincha. TiO2 Surface Hybridisation with Noble Metals (Ag and CuxO) for Solar De-NOx and VOC Removal. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Luc Lajaunie; Maria Paula Seabra; Raul Arenal; Joao Antonio Labrincha. 2020. "TiO2 Surface Hybridisation with Noble Metals (Ag and CuxO) for Solar De-NOx and VOC Removal." , no. : 1.
Electrochemical sensors for monitoring biochemical substances are attracting considerable attention. These devices are usually based on enzymes that are sensitive and very specific. Still, the activity of those enzymes is lost with changes in temperature or pH. Non-enzymatic electrochemical sensors – fabricated via the modification of the electrode surface with metal oxide nanoparticles – are a judicious answer. In this study, we investigated the photo-electrochemical properties of CuO–TiO2 heterojunctions for glucose sensing in alkaline media. A combination of high-resolution (scanning) transmission electron microscopy, spatially resolved electron energy-loss spectroscopy, energy-dispersive X-ray spectroscopy and X-ray powder diffraction, was used to study in detail the microstructures of the prepared specimens. These results highlighted the strong intertwining between the TiO2 nanoparticles and the Cu-based nanoparticles, which present a metallic core with a CuO rich surface. In addition, we showed that CuO, joint to TiO2, has smaller size compared to pure CuO, which entails larger surface area available for the glucose electro-oxidation, which consequently enhanced the electrochemical features. The influence of Cu loading over the sensing performance of TiO2 was examined in detail carrying out electrochemical sensing tests under dark, laboratory and halogen lamp irradiation. Results demonstrated that, under halogen lamp irradiation, modified CuO–TiO2 electrodes showed a higher specific response signal than that of pure CuO. Those increased photo-electrochemical properties in CuO–TiO2 heterojunctions are likely due to a synergistic effect between the microstructural characteristics and effective separation of photo-generated exciton created at the heterojunction interface. Results of this study offer applicable guidelines for designing photo-electrochemical screen-printed electrodes based on nano-sized CuO on titania for an efficient detection of glucose.
David Maria Tobaldi; Claudia Espro; Salvarore Gianluca Leonardi; Luc Lajaunie; Maria Paula Seabra; José Calvino; Silvia Marini; Joao Antonio Labrincha; Giovanni Neri. Photo-Electrochemical Properties of CuO–TiO2 Heterojunctions for Glucose Sensing. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Claudia Espro, Salvarore Gianluca Leonardi, Luc Lajaunie, Maria Paula Seabra, José Calvino, Silvia Marini, Joao Antonio Labrincha, Giovanni Neri. Photo-Electrochemical Properties of CuO–TiO2 Heterojunctions for Glucose Sensing. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Claudia Espro; Salvarore Gianluca Leonardi; Luc Lajaunie; Maria Paula Seabra; José Calvino; Silvia Marini; Joao Antonio Labrincha; Giovanni Neri. 2020. "Photo-Electrochemical Properties of CuO–TiO2 Heterojunctions for Glucose Sensing." , no. : 1.
Electrochemical sensors for monitoring biochemical substances are attracting considerable attention. These devices are usually based on enzymes that are sensitive and very specific. Still, the activity of those enzymes is lost with changes in temperature or pH. Non-enzymatic electrochemical sensors – fabricated via the modification of the electrode surface with metal oxide nanoparticles – are a judicious answer. In this study, we investigated the photo-electrochemical properties of CuO–TiO2 heterojunctions for glucose sensing in alkaline media. A combination of high-resolution (scanning) transmission electron microscopy, spatially resolved electron energy-loss spectroscopy, energy-dispersive X-ray spectroscopy and X-ray powder diffraction, was used to study in detail the microstructures of the prepared specimens. These results highlighted the strong intertwining between the TiO2 nanoparticles and the Cu-based nanoparticles, which present a metallic core with a CuO rich surface. In addition, we showed that CuO, joint to TiO2, has smaller size compared to pure CuO, which entails larger surface area available for the glucose electro-oxidation, which consequently enhanced the electrochemical features. The influence of Cu loading over the sensing performance of TiO2 was examined in detail carrying out electrochemical sensing tests under dark, laboratory and halogen lamp irradiation. Results demonstrated that, under halogen lamp irradiation, modified CuO–TiO2 electrodes showed a higher specific response signal than that of pure CuO. Those increased photo-electrochemical properties in CuO–TiO2 heterojunctions are likely due to a synergistic effect between the microstructural characteristics and effective separation of photo-generated exciton created at the heterojunction interface. Results of this study offer applicable guidelines for designing photo-electrochemical screen-printed electrodes based on nano-sized CuO on titania for an efficient detection of glucose.
David Maria Tobaldi; Claudia Espro; Salvarore Gianluca Leonardi; Luc Lajaunie; Maria Paula Seabra; José Calvino; Silvia Marini; Joao Antonio Labrincha; Giovanni Neri. Photo-Electrochemical Properties of CuO–TiO2 Heterojunctions for Glucose Sensing. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Claudia Espro, Salvarore Gianluca Leonardi, Luc Lajaunie, Maria Paula Seabra, José Calvino, Silvia Marini, Joao Antonio Labrincha, Giovanni Neri. Photo-Electrochemical Properties of CuO–TiO2 Heterojunctions for Glucose Sensing. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Claudia Espro; Salvarore Gianluca Leonardi; Luc Lajaunie; Maria Paula Seabra; José Calvino; Silvia Marini; Joao Antonio Labrincha; Giovanni Neri. 2020. "Photo-Electrochemical Properties of CuO–TiO2 Heterojunctions for Glucose Sensing." , no. : 1.
Hydrogen, as energy carrier, is a zero-emission fuel. Being green and clean, it is considered to play an important role in energy and environmental issues. Photocatalytic water splitting is a process used to generate hydrogen from the dissociation of water. Titanium dioxide is still the archetype material for photocatalytic water splitting. However, because of the fast recombination of the photo-generated exciton, the yield of the reaction is typically low. In this work, we have modified the surface of titanium dioxide with copper and copper/graphene to sensitise it to visible light, and to increase the spatial charge carrier separation, thus extending the quantum yield of H2 production from methanol/water mixtures. Results showed that, in the analysed system, exists an optimum amount of copper plus graphene (i.e. 0.5 mol% copper plus 0.5 wt% graphene) to grant a two-fold increase in the photocatalytic hydrogen generation compared to that of bare titania. That system proved itself to be complex and dynamic. This was attributed to the increased spatial charge carrier separation exploited by graphene (under 365 and 405 nm irradiation), and to the continuous reduction of Cu(II) to Cu(I) due to IFCT that has proven to be an excellent visible-light sensitiser in the copper/graphene-titania system.Hybrid titania-copper-graphene materials could therefore be exploited in the field of light-to-energy applications.
David Maria Tobaldi; Kamila Koci; Miroslava Edelmannova; Luc Lajaunie; Bruno Figueiredo; José Calvino; Maria Paula Seabra; Joao Antonio Labrincha. Copper-Graphene-TiO2 Hybrid Materials for Photocatalytically Assisted H2 Generation. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Kamila Koci, Miroslava Edelmannova, Luc Lajaunie, Bruno Figueiredo, José Calvino, Maria Paula Seabra, Joao Antonio Labrincha. Copper-Graphene-TiO2 Hybrid Materials for Photocatalytically Assisted H2 Generation. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Kamila Koci; Miroslava Edelmannova; Luc Lajaunie; Bruno Figueiredo; José Calvino; Maria Paula Seabra; Joao Antonio Labrincha. 2020. "Copper-Graphene-TiO2 Hybrid Materials for Photocatalytically Assisted H2 Generation." , no. : 1.
Hydrogen, as energy carrier, is a zero-emission fuel. Being green and clean, it is considered to play an important role in energy and environmental issues. Photocatalytic water splitting is a process used to generate hydrogen from the dissociation of water. Titanium dioxide is still the archetype material for photocatalytic water splitting. However, because of the fast recombination of the photo-generated exciton, the yield of the reaction is typically low. In this work, we have modified the surface of titanium dioxide with copper and copper/graphene to sensitise it to visible light, and to increase the spatial charge carrier separation, thus extending the quantum yield of H2 production from methanol/water mixtures. Results showed that, in the analysed system, exists an optimum amount of copper plus graphene (i.e. 0.5 mol% copper plus 0.5 wt% graphene) to grant a two-fold increase in the photocatalytic hydrogen generation compared to that of bare titania. That system proved itself to be complex and dynamic. This was attributed to the increased spatial charge carrier separation exploited by graphene (under 365 and 405 nm irradiation), and to the continuous reduction of Cu(II) to Cu(I) due to IFCT that has proven to be an excellent visible-light sensitiser in the copper/graphene-titania system.Hybrid titania-copper-graphene materials could therefore be exploited in the field of light-to-energy applications.
David Maria Tobaldi; Kamila Koci; Miroslava Edelmannova; Luc Lajaunie; Bruno Figueiredo; José Calvino; Maria Paula Seabra; Joao Antonio Labrincha. Copper-Graphene-TiO2 Hybrid Materials for Photocatalytically Assisted H2 Generation. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Kamila Koci, Miroslava Edelmannova, Luc Lajaunie, Bruno Figueiredo, José Calvino, Maria Paula Seabra, Joao Antonio Labrincha. Copper-Graphene-TiO2 Hybrid Materials for Photocatalytically Assisted H2 Generation. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Kamila Koci; Miroslava Edelmannova; Luc Lajaunie; Bruno Figueiredo; José Calvino; Maria Paula Seabra; Joao Antonio Labrincha. 2020. "Copper-Graphene-TiO2 Hybrid Materials for Photocatalytically Assisted H2 Generation." , no. : 1.
Calcareous sludge is an alkaline waste produced by the paper pulp industry that is commonly disposed of in land-fill. However, recent studies and the European regulations discourage such practice. This work investigates an alternative and innovative way to recycle and reuse this waste, as filler, in the production of green geopolymeric mortars intended for applications in construction. This is the first time that this calcareous sludge is used to produce novel waste-based materials, in both construction and geopolymer technology. The novel alkali-activated mortar also uses biomass fly ash – another slightly investigated waste stream – to substitute the metakaolin (70 wt% substitution) and the manufacture process is performed at ambient conditions. All of that reduces the overall process footprint. The implemented mix design is aimed at maximising the waste incorporation and improving the material properties, such as workability and mechanical performance. The main results demonstrate that 10 wt% of calcareous sludge can be efficaciously used as filler in the geopolymeric mortars, generating up to 30% improvement in the mechanical resistance. This alternative use of such wastes will contribute to increase the sustainability of the novel construction materials also granting environmental advantages and a financial surplus for the industry.
Manfredi Saeli; Luciano Senff; David Maria Tobaldi; João Carvalheiras; Maria Paula Seabra; Joao Labrincha. Unexplored alternative use of calcareous sludge from the paper-pulp industry in green geopolymer construction materials. Construction and Building Materials 2020, 246, 118457 .
AMA StyleManfredi Saeli, Luciano Senff, David Maria Tobaldi, João Carvalheiras, Maria Paula Seabra, Joao Labrincha. Unexplored alternative use of calcareous sludge from the paper-pulp industry in green geopolymer construction materials. Construction and Building Materials. 2020; 246 ():118457.
Chicago/Turabian StyleManfredi Saeli; Luciano Senff; David Maria Tobaldi; João Carvalheiras; Maria Paula Seabra; Joao Labrincha. 2020. "Unexplored alternative use of calcareous sludge from the paper-pulp industry in green geopolymer construction materials." Construction and Building Materials 246, no. : 118457.
Nanostructured systems showing reversible colour switching are envisaged to play a significant role in photo-switches, photo-optical sensors, smart windows, displays, optical storage memories. Most of the materials exhibiting reversible colour switching are organic compounds. However, their UV-light activation, low thermal and chemical stability, as well as harmful synthesis methods, are of limit for their extensive use. In this research, we have created an inorganic switchable photochromic material exploiting: (i) TiO2 ability of creating an exciton upon excitation, (ii) copper as the chromophore, and (iii) graphene’s extraordinarily high electron mobility. Our material showed itself to be able to work under visible-light, its photochromic property being three times faster than conventional titania based photochromic materials, reaching a stable change in colouration after only 30 mins of visible-light irradiation (versus > 120 min in conventional Cu-TiO2). With the addition of just 1 wt% graphene, the material exhibited a staggeringly stable photochromic switching over repeated cycles. These results relate to the best previously reported values for any form of TiO2-based photochromic material. This is therefore an excellent candidate for smart self-cleaning windows, and other chromic devices and applications.
David Maria Tobaldi; Luc Lajaunie; Dana Dvoranova; Bruno Figueiredo; Maria Paula Seabra; José Calvino; Vlasta Brezova; Joao Antonio Labrincha. Cooperative and Fully Reversible Photocatalytic Colour Switching Activation in Graphene-Copper-TiO2 Nanoparticles. 2020, 1 .
AMA StyleDavid Maria Tobaldi, Luc Lajaunie, Dana Dvoranova, Bruno Figueiredo, Maria Paula Seabra, José Calvino, Vlasta Brezova, Joao Antonio Labrincha. Cooperative and Fully Reversible Photocatalytic Colour Switching Activation in Graphene-Copper-TiO2 Nanoparticles. . 2020; ():1.
Chicago/Turabian StyleDavid Maria Tobaldi; Luc Lajaunie; Dana Dvoranova; Bruno Figueiredo; Maria Paula Seabra; José Calvino; Vlasta Brezova; Joao Antonio Labrincha. 2020. "Cooperative and Fully Reversible Photocatalytic Colour Switching Activation in Graphene-Copper-TiO2 Nanoparticles." , no. : 1.