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Artículos SCI



2023


Materiales Semiconductores para la Sostenibilidad

Surfactant-Dependent Bulk Scale Mechanochemical Synthesis of CsPbBr3 Nanocrystals for Plastic Scintillator-Based X-ray Imaging

Ghosh, J; O'Neill, J; Masteghin, MG; Braddock, I; Crean, C; Dorey, R; Salway, H; Anaya, M; Reiss, J; Wolfe, D; Sellin, P
ACS Applied Nano Materials,

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We report a facile, solvent-free surfactant-dependentmechanochemicalsynthesis of highly luminescent CsPbBr3 nanocrystals (NCs)and study their scintillation properties. A small amount of surfactantoleylamine (OAM) plays an important role in the two-step ball millingmethod to control the size and emission properties of the NCs. Thesolid-state synthesized perovskite NCs exhibit a high photoluminescencequantum yield (PLQY) of up to 88% with excellent stability. CsPbBr3 NCs capped with different amounts of surfactant were dispersedin toluene and mixed with polymethyl methacrylate (PMMA) polymer andcast into scintillator discs. With increasing concentration of OAMduring synthesis, the PL yield of CsPbBr3/PMMA nanocompositewas increased, which is attributed to reduced NC aggregation and PLquenching. We also varied the perovskite loading concentration inthe nanocomposite and studied the resulting emission properties. Themost intense PL emission was observed from the 2% perovskite-loadeddisc, while the 10% loaded disc exhibited the highest radioluminescence(RL) emission from 50 kV X-rays. The strong RL yield may be attributedto the deep penetration of X-rays into the composite, combined withthe large interaction cross-section of the X-rays with the high-Zatoms within the NCs. The nanocomposite disc shows an intense RL emissionpeak centered at 536 nm and a fast RL decay time of 29.4 ns. Further,we have demonstrated the X-ray imaging performance of a 10% CsPbBr3 NC-loaded nanocomposite disc.


Agosto, 2023 | DOI: 10.1021/acsanm.3c02531

Química de Superficies y Catálisis

H2-rich syngas production from biogas reforming: Overcoming coking and sintering using bimetallic Ni-based catalysts

Carrasco-Ruiz, S; Zhang, Q; Gándara-Loe, J; Pastor-Pérez, L; Odriozola, JA; Reina, TR; Bobadilla, LF
International Journal of Hydrogen Energy, 48 (2023) 72

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Dry reforming of methane is a very appealing catalytic route biogas (mainly composed by greenhouse gases: carbon dioxide and methane) conversion into added value syngas, which could be further upgraded to produce liquid fuels and added value chemicals. However, the major culprits of this reaction are coking and active phase sintering that result in catalysts deactivation. Herein we have developed a highly stable bimetallic Ni–Rh catalyst supported on mixed CeO2–Al2O3 oxide using low-noble metal loadings. The addition of small amounts of rhodium to nickel catalysts prevents coke formation and improves sintering resistance, achieving high conversions over extended reaction times hence resulting in promising catalysts for biogas upgrading.


Agosto, 2023 | DOI: 10.1016/j.ijhydene.2023.03.301

Química de Superficies y Catálisis

Effect of noble metal addition over active Ru/TiO2 catalyst for CO selective methanation from H2 rich- streams

Bobadilla, LF; Muñoz-Murillo, A; Gandara-Loe, J; Perez, A; Laguna, OH; Martinez, TLM; Penkova, A; Centeno, MA; Odriozola, JA
International Journal of Hydrogen Energy, 48 (2023) 25065-25074

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Selective CO methanation from H2-rich stream has been regarded as a promising route for deep removal of low CO concentration and catalytic hydrogen purification processes. This work is focused on the development of more efficient catalysts applied in practical conditions. For this purpose, we prepared a series of catalysts based on Ru supported over titania and promoted with small amounts of Rh and Pt. Characterization details revealed that Rh and Pt modify the electronic properties of Ru. The results of catalytic activity showed that Pt has a negative effect since it promotes the reverse water gas shift reaction decreasing the selectivity of methanation but Rh increases remarkably the activity and selectivity of CO methanation. The obtained results suggest that RuRh-based catalyst could become important for the treatment of industrial-volume streams.


Julio, 2023 | DOI: 10.1016/j.ijhydene.2022.07.072

Reactividad de Sólidos

R-curve evaluation of 3YTZP/graphene composites by indirect compliance method

Lopez-Pernia, C; Munoz-Ferreiro, C; Prada-Rodrigo, J; Moreno, P; Reveron, H; Chevalier, J; Morales-Rodriguez, A; Poyato, R; Gallardo-Lopez, A
Journal of the European Ceramic Society, 43 (2022) 3486-3497

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This work addresses the crack growth resistance of 3 mol% Yttria-doped Tetragonal Zirconia Polycrystalline (3YTZP) spark-plasma sintered (SPS) composites containing two types of graphene-based nanomaterials (GBN): exfoliated graphene nanoplatelets (e-GNP) and reduced graphene oxide (rGO). The crack growth resistance of the composites is assessed by means of their R-Curve behavior determined by three-point bending tests on single edge "V" notched beams (SEVNB), in two different orientations of the samples: with the crack path perpendicular or parallel to the pressure axis during the SPS sintering. The sharp edge notches were machined by ultrashort laser pulsed ablation (UPLA). The compliance and optical-based methods for evaluating the crack length are compared on the basis of the experimental R-Curve results in composites with 2.5 vol% rGO tested in the perpendicular orientation. Moreover, the activation of reinforcement mechanisms is evaluated by both the fracture surface inspection by Scanning Electron Microscopy and a compliance analysis. It is shown that the indirect compliance method is relevant and reliable for calculating the R-Curve of 3YTZP/GBN composites. The effect of the type and content of GBN on the crack growth resistance of the composites is also discussed.


Julio, 2023 | DOI: 10.1016/j.jeurceramsoc.2023.02.002

Nanotecnología en Superficies y Plasma

Dielectric multilayers for broadband optical rotation enhancement

Pellegrini, G; Mogni, E; Gil-Rostra, J; Yubero, F; Fossati, S; Dostálek, J; Vázquez, RM; Osellame, R; Celebrano, M; Finazzi, M; Biagioni, P
Nuovo Cimento C-Colloquia and Communications in Physics, 46 (2023) 111

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We design a simple dielectric multilayer capable of sustaining broadband superchiral surface waves. We show that the platform can produce large optical chirality enhancements in a wavelength range of hundreds of nanometers. We finally demonstrate that these properties result in the enhancement of the optical rotation signal well above two orders of magnitude, thus extending surface-enhanced chiral spectroscopies beyond the traditionally addressed circular dichroism signals.


Julio, 2023 | DOI: 10.1393/ncc/i2023-23111-1

 

 

 

 

 

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