Effects of In-Air Post Deposition Annealing Process on the Oxygen Vacancy Content in Sputtered GDC Thin Films Probed via Operando XAS and Raman Spectroscopy.

We investigate the ionic mobility in room-temperature RF-sputtered gadolinium doped ceria (GDC) thin films grown on industrial solid oxide fuel cell substrates as a function of the air-annealing at 800 and 1000 °C. The combination of X-ray diffraction, X-ray photoelectron spectroscopy, operando X-ray absorption spectroscopy, and Raman spectroscopy allows us to study the different Ce/ Ce ratios induced by the post growth annealing procedure, together with the Ce valence changes induced by different gas atmosphere exposure. Our results give evidence of different kinetics as a function of the annealing temperature, with the sample annealed at 800 °C showing marked changes of the Ce oxidation state when exposed to both reducing and oxidizing gas atmospheres at moderate temperature (300 °C), while the Ce valence is weakly affected for the 1000 °C annealed sample.

Effect of microplastics on urban wastewater disinfection and impact on effluent reuse: Sunlight/HO vs solar photo-Fenton at neutral pH.

The interference of three types of microplastics (MPs) on the inactivation of Escherichia coli (E. coli) by advanced oxidation processes (AOPs) (namely, sunlight/HO and solar photo-Fenton (SPF) with Ethylenediamine-N,N'-disuccinic acid (EDDS)), in real secondary treated urban wastewater was investigated for the first time. Inactivation by sunlight/HO treatment decreased as MPs concentration and HO dose were increased.

Emergence and Evolution of Crystallization in TiO Thin Films: A Structural and Morphological Study.

Among all transition metal oxides, titanium dioxide (TiO) is one of the most intensively investigated materials due to its large range of applications, both in the amorphous and crystalline forms. We have produced amorphous TiO thin films by means of room temperature ion-plasma assisted e-beam deposition, and we have heat-treated the samples to study the onset of crystallization. Herein, we have detailed the earliest stage and the evolution of crystallization, as a function of both the annealing temperature, in the range 250-1000 °C, and the TiO thickness, varying between 5 and 200 nm.

Fabrication of SrTiO₃ Layer on Pt Electrode for Label-Free Capacitive Biosensors.

Due to their interesting ferroelectric, conductive and dielectric properties, in recent years, perovskite-structured materials have begun to attract increasing interest in the biosensing field. In this study, a strontium titanate perovskite layer (SrTiO₃) has been synthesized on a platinum electrode and exploited for the development of an impedimetric label-free immunosensor for O157:H7 detection. The electrochemical characterization of the perovskite-modified electrode during the construction of the immunosensor, as well as after the interaction with different O157:H7 concentrations, showed a reproducible decrease of the total capacitance of the system that was used for the analytical characterization of the immunosensor.

Graphene field effect transistors with niobium contacts and asymmetric transfer characteristics.

We fabricate back-gated field effect transistors using niobium electrodes on mechanically exfoliated monolayer graphene and perform electrical characterization in the pressure range from atmospheric down to 10(-4) mbar. We study the effect of room temperature vacuum degassing and report asymmetric transfer characteristics with a resistance plateau in the n-branch. We show that weakly chemisorbed Nb acts as p-dopant on graphene and explain the transistor characteristics by Nb/graphene interaction with unpinned Fermi level at the interface.