Menú secundario

Artículos SCI



2019


Nanotecnología en Superficies y Plasma

Sodium ion storage performance of magnetron sputtered WO3 thin films

Garcia-Garcia, FJ; Mosa, J; Gonzalez-Elipe, AR; Aparicio, M
Electrochimica Acta, 321 (2019) 134669

Show abstract ▽

WO3 thin film electrodes were successfully prepared by magnetron sputtering (MS) deposition under an oblique angle configuration (OAD). Intercalation of Na ions in the tungsten oxide layers has been studied using electrochemical techniques. Sample characterization before and after sodium intercalation has been carried out by Raman, XPS and XRD measurements. ToF-SIMS analysis has been also performed in order to analyze the element depth profiles along the electrode thickness. Electron microscopy evaluation of the cross section confirms the porous structure of the coatings. Batteries integrating these WO3 electrodes have a discharge capacity of 120 mA h g(-1) at the initial cycles and show an adequate capacity retention upon 300 cycles. The WO3-OAD thin-films are proposed as promising electrodes for Na-ion batteries.


Octubre, 2019 | DOI: 10.1016/j.electacta.2019.134669

Materiales Ópticos Multifuncionales

Spatially Resolved Analysis of Defect Annihilation and Recovery Dynamics in Metal Halide Perovskite Single Crystals

Galisteo-Lopez, JF; Calvo, ME; Miguez, H
ACS Applied Energy Materials, 2 (2019) 6967-6972

Show abstract ▽

The spectacular advances in efficiency of optoelectronic devices based on lead-halide perovskites have been accompanied by detailed structural and optical studies regarding the instability presented by these materials, which constitute their main bottleneck for commercialization. Following a pump and probe scheme in a laser scanning confocal microscope, we resolve the photoinduced emission activation/deactivation dynamics in CH3NH3PbBr3 single crystals with millisecond and sub-micrometer resolution. This is complemented with a study of spectral variations and interpreted in the framework of light-induced ion migration and associated defect passivation. Our results point to the presence of photoinduced structural changes accompanying the migration of ions.


Octubre, 2019 | DOI: 10.1021/acsaem.9b01335

Materiales Coloidales - Materiales Ópticos Multifuncionales

Synthesis, functionalization and properties of uniform europium-doped sodium lanthanum tungstate and molybdate (NaLa(XO4)(2), X = Mo,W) probes for luminescent and X-ray computed tomography bioimaging

Laguna, M; Nunez, NO; Becerro, AI; Lozano, G; Moros, M; de la Fuente, JM; Corral, A; Balcerzyk, M; Ocana, M
Journal of Colloid and Interface Science, 554 (2019) 520-530

Show abstract ▽

A one-pot simple procedure for the synthesis of uniform, ellipsoidal Eu3+-doped sodium lanthanum tungstate and molybdate (NaLa(XO4)(2), X = W, Mo) nanophosphors, functionalized with carboxylate groups, is described. The method is based on a homogeneous precipitation process at 120 degrees C from appropriate Na+ Ln(3+) and tungstate or molybdate precursors dissolved in ethylene glycol/water mixtures containing poly acrylic acid. A comparative study of the luminescent properties of both luminescent materials as a function of the Eu3+ doping level has been performed to find the optimum nanophosphor, whose efficiency as X-ray computed tomography contrast agent is also evaluated and compared with that of a commercial probe. Finally, the cell viability and colloidal stability in physiological pH medium of the optimum samples have also been studied to assess their suitability for biomedical applications.


Octubre, 2019 | DOI: 10.1016/j.jcis.2019.07.031

Química de Superficies y Catálisis

The Success Story of Gold-Based Catalysts for Gas- and Liquid-Phase Reactions: A Brief Perspective and Beyond

Price, CAH; Pastor-Perez, L; Ivanova, S; Reina, TR; Liu, J
Frontiers in Chemistry, 7 (2019) 691

Show abstract ▽

Gold has long held the fascination of mankind. For millennia it has found use in art, cosmetic metallurgy and architecture; this element is seen as the ultimate statement of prosperity and beauty. This myriad of uses is made possible by the characteristic inertness of bulk gold; allowing it to appear long lasting and above the tarnishing experienced by other metals, in part providing its status as the most noble metal.


Octubre, 2019 | DOI: 10.3389/fchem.2019.00691

Química de Superficies y Catálisis

Montmorillonite-stabilized gold nanoparticles for nitrophenol reduction

Chenouf, M; Megias-Sayago, C; Ammari, F; Ivanova, S; Centeno, MA; Odriozola, JA
Comptes Rendus Chimie, 22 (2019) 621-627

Show abstract ▽

Two gold-based catalysts were obtained by Au chemical reduction of the HAuCl(4 )precursor. The resulting nanoparticles were stabilized and immobilized on montmorillonite (Mt) and montmorillonite-ceria (Mt/CeO2). All prepared catalysts were active in 4-nitrophenol to aminophenol reduction at room temperature. Synergy between montmorillonite and ceria is postulated in such a way that the montmorillonite phase hinders particle growth either by influencing the nucleation behavior of gold or by increasing the number of nucleation sites and raising the overall dispersion. The role of the ceria support, on the other hand, may be associated with the 4-NP adsorption at the ceria-gold interface, stabilizing the reaction intermediate and hence lowering the activation barrier for the reduction of 4-NP to 4-AP. 


Septiembre, 2019 | DOI: 10.1016/j.crci.2019.07.005

 

 

 

 

 

icms