The effect of the incorporation of silver nanoparticles (Ag-NPs) on the electrochemical behavior of symmetrical La0.1Sr0.9TiO3 (LST)/ La0.4Ce0.6O2 (LDC)/ La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM) cells is presented. Ag-NPs were infiltrated into LST anodes by using a wet chemical reduction technique. The cells with different concentrations of Ag-NPs were prepared by modifying the immersion time in a reducing solution. The Ag-NPs infiltrated were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The analysis of the fraction of AgNPs incorporated into the cells was performed by X-ray diffraction (XRD) and particle-induced X-ray emission (PIXE). The effect of the Ag-NPs on the electrochemical behavior of the obtained electrodes was studied by electrochemical impedance spectroscopy (EIS), varying the hydrogen partial pressure. The EIS spectra obtained were analyzed by the distribution of relaxation times (DRT). The results of this study indicated that the infiltration of Ag-NPs improved the electrochemical response of the LST anodes by reducing their ohmic losses due to the increase in electronic conductivity. In this regard, incorporating 16 wt % of silver nanoparticles led to a 70% decrease in the area-specific resistance (ASR) of the LST. Furthermore, it was observed that the Ag-NPs infiltrated acted as catalysts of the hydrogen oxidation reaction (HOR), decreasing the overpotential and affecting the mechanisms that limit the HOR.

The thin film approach for Solid Oxide Cell (SOC) electrolytes offers a pathway to reduce the high fabrication and operating temperatures of these devices. In this work, we present a detailed ex situ and in situ study of 8 mol% yttria-stabilized zirconia (8YSZ) nanostructured dense thin films with a thickness of 100 nm. These films were synthesised through the sol-gel method and deposited by dip-coating on fused glass. The microstructural and crystalline evolution in the 300-800 degrees C range was studied by synchrotron Grazing Incidence X-ray Diffraction (GIXRD). Crystallisation of the 8YSZ films was observed to start at 343 degrees C with 4-5 nm crystallites consisting only of the cubic phase. With increasing temperature, this phase is maintained and the crystallite size reaches 38 nm at 800 degrees C. Additionally, the evolution of the lattice parameter was studied, which allowed us to determine the variation of the thermal expansion coefficient (TEC) of the films during both heating and cooling. The TEC as a function of temperature has three linear regions during heating and two during cooling, with values between 9.6 x 10-7 K-1 and 3.7 x 10-5 K-1. These findings provide valuable insights into the structural response of the material under thermal cycling, relevant to the performance and stability of SOC devices. Coupled with the crystallographic characterisation, the electrical properties of the thin films were studied through conductivity measurements, obtaining conductivities about 1.5 to 5 times higher than the conductivity of 8YSZ bulk samples, with values of 0.06 S cm-1 at 700 degrees C. Thus, the conjunction of a reduced electrolyte thickness with the enhanced conductivity of nanostructured 8YSZ makes these films attractive for intermediate-temperature SOC applications.

La0.1Sr0.9TiO3 (LST) perovskite has been studied as anode material for Intermediate Temperature Solid Oxide Fuel Cell (IT-SOFC) applications. LST powders were synthesized by two chemical methods, one employed hexamethylenetetramine (HMTA) as a complexing agent while the other utilized ethylenediaminetetraacetic acid (EDTA). These approaches yielded different microstructures as evidenced by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and N2 adsorption/desorption isotherms studies. The effect of the microstructure on the electrochemical behavior of the obtained electrodes was studied by Electrochemical Impedance Spectroscopy (EIS) by varying the hydrogen partial pressure and the temperature. In addition, the evolution of specific area resistance with the hydrogen partial pressure allowed the identification of the reaction mechanism. The results of EIS were studied by electrical equivalent circuit (EEC) and distribution of relaxation times (DRT). The results suggest that the hydrogen oxidation reaction (HOR) limiting step for both samples is controlled by hydrogen dissociative-adsorption at the surface. The hydrogen adsorption is faster at the electrode formed by smaller nanoparticles, in which the activation energy decreases and the rate coefficient changes.

The electrode microstructure in solid oxide fuel cells plays a significant role in transport and reaction phenomena. It requires interconnected pores for gas diffusion and a percolating network for efficient charge transport. Yttria-stabilized zirconia is a commonly used material for electrode scaffolds since it can be structured at the meso/nanoscale for improved performance, besides its high ionic conductivity, stability, and cost-effectiveness balance. However, electrode degradation remains challenging when supplied with hydrocarbons and requires further optimization. This study focuses on developing mesoporous yttria-stabilized zirconia as a precursor for a highly porous scaffold, and its infiltration with copper and cerium solution to obtain the metal-oxide composite Cu–CeO2/YSZ. Two types of symmetrical cells were constructed and analyzed: thin anode cells and thick anode cells. Thin anode cells were useful for selecting the best temperature for heat treatment of the YSZ scaffold, considering its effect on the electrode/electrolyte interface, grain interconnection, and infiltrated phase distribution, as well as how these microstructural features influence electrochemical performance in a methane atmosphere. Cell processing was then optimized by switching to thick anode cells, reducing the electrode resistance by an order of magnitude. These results were compared with those of an electrode scaffold fabricated from commercial YSZ, concluding that the powder mesostructure was crucial in improving electrode microstructure, reducing polarization resistance, and enhancing temporal stability in a direct methane-fueled cell.

Ni-based state-of-the-art cermet electrodes for SOFC are prone to deactivation when using hydrocarbon-based fuels due to surface carbon deposition. CeO2-based oxides offer major advantages to improve long-term performance of electrodes, such as high oxygen transport properties, carbon deposition resistance and optimum chemical compatibility with intermediate temperature SOFC (IT-SOFC) high performance electrolytes. Ceria-containing electrodes are generally mixed with Ni or other metallic phases to improve electronic percolation. In this work, we present two Ni-free electrodes: Ce0.9Zr0.1O2-δ and Ce0.9Zr0.06Sc0.04O2-δ. These electrodes exhibit a large amount of electrochemical reaction sites due to the nanoscale particle size distribution of the electrode material (Dav=25 nm). We show that, by partially replacing Zr by Sc in the Ce0.9Zr0.1O2 lattice, the polarization resistance of the electrode is significantly improved. The Sc-containing system exhibited a superior performance especially when using CH4 as fuel, thus implying that the incorporation of additional oxygen vacancies in the lattice enhances the electrode activity for fuel oxidation and its resistance towards carbon formation. These results reveal that the Ce0.9Zr0.06Sc0.04O2-δ electrode stands both as a promising Ni-free anode for IT-SOFC/SOEC operation and as a highly active redox support for Ni-based cermets.

Exsolution is one of the most successful functionalization techniques to improve the catalytic activity of electrodes in solid oxide fuel and electrolyzer cells (SOFC/SOEC). The objective of this technique is to produce the highest possible number of metallic nanoparticles on the surface of a host-oxide, without significantly altering its structure. In this work, we compare three similar SOFC electrodes: STF (SrTi0.3Fe0.7O3), STFN (Sr0.93Ti0.3Fe0.63Ni0.07O3), and STFNC (Sr0.93Ti0.3Fe0.56Ni0.07Co0.07O3), revealing that there is a significant difference between Ni–Fe/Ni–Co–Fe nanoparticle formation in STFN/STFNC and pure Fe0 particle formation in STF, which is evidenced by the size and amount of produced nanoparticles, but also by their anchoring to the host-oxide. The terms exsolution and particle segregation will be used, respectively, to distinguish these phenomena. Next, we explore two different reduction methods and observe that the characteristics of exsolution do not only depend on temperature, atmosphere and reduction times, but also on the reduction path taken to reach such conditions.

In magnetic tunnel junctions based on iron oxide nanoparticles the disorder and the oxidation state of the surface spin as well as the nanoparticles functionalization play a crucial role in the magnetotransport properties. In this work, we report a systematic study of the effects of vacuum annealing on the structural, magnetic and transport properties of self-assembled ∼10 nm Fe3O4nanoparticles. The high temperature treatment (from 573 to 873 K) decomposes the organic coating into amorphous carbon, reducing the electrical resistivity of the assemblies by 4 orders of magnitude. At the same time, the 3.Fe2+/(Fe3++Fe2+) ratio is reduced from 1.11 to 0.13 when the annealing temperature of the sample increases from 573 to 873 K, indicating an important surface oxidation. Although the 2 nm physical gap remains unchanged with the thermal treatment, a monotonous decrease of tunnel barrier width was obtained from the electron transport measurements when the annealing temperature increases, indicating an increment in the number of defects and hot-spots in the gap between the nanoparticles. This is reflected in the reduction of the spin dependent tunneling, which reduces the interparticle magnetoresistance. This work shows new insights about influence of the nanoparticle interfacial composition, as well their the spatial arrangement, on the tunnel transport of self-assemblies, and evidence the importance of optimizing the nanostructure fabrication for increasing the tunneling current without degrading the spin polarized current.

Herein, we report the synthesis of graphene quantum dots (GQDs) functionalized with 1,5-diphenylcarbazone for the selective quantification of Fe, within wine beverages, via front-face fluorescence. GQDs are obtained via a clean and relatively size-controlled synthesis based on the electrochemical exfoliation from a graphene foam. The product of the synthesis was later functionalized to solely detect Fe within various other ions present within the sample. The detection mechanism relays on the quenching of the emission of the functionalized material by Fe3+, which follows the Stern-Volmer model, that proposes a linear relationship between the degree of quenching and the concentration of the analyte. Diverse parameters involved in the measurements, including the pH and optimal excitation wavelength, were optimized, giving place to limits of detection of 0.014 mg L-1 and 0.11 mg L-1 in waters and white wines, respectively. A soft UV-based digestion and an in-depth analysis of interferences were key factors to achieve such low limits of detection. Furthermore, front-face fluorescence measurements avoided usual matrix shielding effects, significantly improving the applicability of the method in these complex samples. Due to the scarce number of reports on the field, the sensitive and selective detection of Fe3+ within real (i.e.; wine) samples represents a major step forward in the area.

Carbon doping is studied in MgB2 pellets during one-step synthesis by solid-state reaction, employing both undoped and carbon-doped boron with and without the addition of nano-SiC. The phase formation during the synthesis as a function of time was followed using powder X-ray diffraction and Rietveld refinement. The superconducting properties were characterized with a magnetometer to investigate doping-induced changes. Mg(B1-xCx)2 is obtained with nano-precipitates and different compositions depending on the synthesis temperature. It is found that the addition of nano-SiC prevents the phase formation at low temperature (700°C). Nevertheless, the best superconducting properties are obtained for the sample treated at 900°C using simultaneously C and SiC, with a critical current density of 105 A cm-2 at 3 T and 20 K, named the 900-20-C-nanoSiC sample.

Herein, we report the synthesis of graphene quantum dots (GQDs) functionalized with 1,5-diphenylcarbazone for the selective quantification of Fe in wine, via front-face fluorescence.Crystalline GQDs are obtained via a clean and relatively size-controlled synthesis based on the electrochemical exfoliation from a graphene foam.The product of the synthesis was later functionalized to solely detect Fe 3+ amongst various other ions present within the sample.The detection is based on quenching the fluorescence emission from the functionalized nanomaterial in the presence of the analyte, which follows a linear relationship with the concentration of the analyte, consistent with the Stern-Volmer model.Diverse parameters involved in the measurements, including the pH and excitation wavelength, were optimized, giving place to limits of detection (LOD) of 0.014 mg L -1 and 0.11 mg L -1 in waters and white wines, respectively.A soft UV-based digestion and a profound analysis of interferences were key factors to achieve such LODs.Furthermore, front-face fluorescence measurements improved the applicability of the method by avoiding the commonly occurring matrix shielding effects.We believe that the sensitive, selective, and fast detection of Fe 3+ within real (i.e.; wine) samples represents a major step forward in the field.

Mixed ionic and electronic conductor (MIEC) oxides have been proposed as candidates to replace Ni/YSZ composites as anodes for Solid Oxide Fuel Cells (SOFC) due to their good stability under C-based fuels. Some MIECs have also demonstrated a good electro-catalytic activity both for oxygen reduction and hydrogen oxidation, making them suitable for symmetric configurations (S-SOFC). This approach presents remarkable advantages for reducing manufacturing and operational costs, as well as for extending the cell’s lifetime by reversing gas flows and thus partially reversing the negative effects of sulphur poisoning and carbon deposition that may happen during operation. Also, the catalytic activity of MIEC electrodes can be improved by functionalizing the oxide surface with active nanoparticles. In this work, we study the formation of Ni-Fe alloy nanoparticles by exsolution from a Sr0.93(Ti0.3Fe0.63Ni0.07)O3-δ (STFN) perovskite in reducing atmospheres, and also the process of reoxidation when the exsolved material is exposed to an oxidizing atmosphere. The initial Sr-deficient composition was chosen to alleviate the segregation of Sr [1], which typically can occur in these materials. Exsolution has previously been reported to improve the electrochemical performance of STFN anodes [2], but the mechanisms underlying the exsolution process and the solid/gas interface are still not well understood. The possibility of using S-SOFC materials that undergo exsolution also raises the question of whether the material is regenerated during reoxidation. While oxidation-induced redissolution of exsolved nanoparticles has been observed for Fe-Co exsolution on La0.8Sr1.2Fe0.9Co0.1O4−δ perovskites [3], for the Ni-Fe exsolution in Sr2(Fe1.4Ni0.1Mo0.5)O6− δ, nanoparticles remained at the surface even after reoxidation [4]. The first case is a very interesting result to achieve larger cell lifetimes, and the latter case is interesting as it opens an additional route to increase the cathode performance. In fact, in ref. [5] Ni exsolution in SrTi0.1Fe0.85Ni0.05O3− δ is deliberately employed as design strategy, fully exploiting the non-reversibility of the exsolution of nanoparticles. However, it is not clear whether Ni-Fe nanoparticles oxidize to form a (Ni,Fe)Ox phase or if Fe is reincorporated into the lattice leaving only NiO particles at the surface. It is also not clear how Sr segregation is affected by the exsolution/reoxidation treatments, or how the reoxidized STFN perovskite is modified compared to the pristine sample. To address these questions directly, ambient pressure X-ray photoelectron and near-edge X-ray absorption fine structure spectroscopy (AP-XPS and NEXAFS) is used to study the chemical structure of STFN in a complete redox cycle in-situ. Based on the measurements, we can provide insights into the chemical states of Fe and Ni and can differentiate the surface and bulk species for Sr and O in each stage of the cycle. We observe that Ni exsolves readily, but we also note that the amount of surface Fe0 increases with increasing H2 content in the reducing atmosphere; Fe0 also increases with the reduction time following an exponential trend until a plateau value is reached within ~1h. Further, we find a significant Sr segregation in reducing atmospheres, which we presume occurs to compensate for the B-site cation exsolution. The amount of Sr segregation remains constant in the nearest surface after reoxidation, but is partially reversed for larger penetration depths; there is also a rapid reversibility in the Fe oxidation state during reoxidation. These observations were complemented with transmission (TEM) and scanning electron microscopy (SEM) studies, with simultaneous energy dispersive spectroscopy (EDS) analysis. In conclusion, we propose a reoxidation-induced reconstruction which forms a Fe- and Sr-rich STF perovskite in the near-surface region, leaving the Ni segregated from the perovskite. Finally, we link the results to the electrochemical impedance spectroscopy (EIS) response of the STFN electrode, observing that this STFN-reoxidized sample shows a significant improvement in its cathode performance compared to the pristine STFN. [1] Fagg, D. P. et al, J. Eur. Ceram. Soc. 21, 1831–1835 (2001). [2] Zhu, T., Troiani, H. E., Mogni, L. V, Han, M. & Barnett, S. A. Joule 2, 478–496 (2018). [3] Zhou, J. et al. Chem. Mater. 28, 2981–2993 (2016). [4] Liu, T. et al. J. Mater. Chem. A 8, 582–591 (2020). [5] Yang, G., Zhou, W., Liu, M. & Shao, Z. ACS Appl. Mater. Interfaces 8, 35308-35314 (2016). Figure 1

Here we report the development of a bifunctional magnetic composite that induces magnetic hyperthermia and shows stable paramagnetic defects after the irradiation with X-ray source. The composite is formed by Zn0.16Fe2.84O4 nanoparticles of 18 (3) nm of diameter embedded in a micrometric carbonated hydroxyapatite matrix. As the magnetic nanoparticles are fixed in the matrix, their magnetic properties were adjusted by the size and composition in order to induce local heating by magnetic losses in presence of an AC magnetic field due to the Neel relaxation mechanism. This behavior was confirmed by measuring the Specific Power Absorption (SPA) of 0.1 wt% of magnetic nanoparticles dispersed in media with different viscosity as chloroform (eta = 0.56 cP) and butter oil (eta = 174 cP) obtaining similar to 111(15) W/g in both cases. Consistently, the magnetic hydroxyapatite composite presents a comparable SPA= 126(19) W/g value. On the other hand, the carbonated hydroxyapatite and the magnetic carbonated hydroxyapatite composite were subjected to X-ray radiation with an equivalent dose of 3 kGy and the generated paramagnetic defects were evaluated by electron paramagnetic resonance spectroscopy. It was observed that the CO2 radical is the main defect produced by the irradiation, and its concentration stabilized after a month. These results confirm the potential of this composite to act as a local nanoheater and as a sensor of ionizing radiation, showing interesting possibilities to be used in studies of nanomedicine where the combination of magnetic hyperthermia and radiotherapy is proposed for oncological treatments. (C) 2022 Elsevier B.V. All rights reserved.

In this work, the characterization of ZrO2 thin films synthesized by the sol-gel method, using two different routes, is presented. Thin films were deposited by dip-coating on glass and Zircaloy-4 (Zry-4) substrates, and heat treated at 500 degrees C under atmospheric air. Characterization was carried out using X-Ray Diffraction (XRD), Grazing Incidence X-Ray Diffraction (GIXRD), High Temperature X-Ray Diffraction (HT-XRD), Raman Spectroscopy (RS), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Electrical properties of films were studied by conductivity measurements. These films present a thickness of 90 and 200 nm on glass, depending on the synthesis route, and consist of nanocrystals with predominantly tetragonal phase. On coated Zry-4, a non-uniform but dense ZrO2 layer without cracks grows, in contrast with the un-coated Zry-4, where a thicker layer was formed with the presence of micro-fissures. A GIXRD study showed that both tetragonal and monoclinic phases are present in the oxide layer. Conductivity measurements indicated that these films have excellent insulating properties, with resistivity values that exceed 0.5 M Omega.cm below 300 degrees C. These exceptional properties and the retention of high symmetry phases make this method very attractive for growing good electrical insulator and anti-corrosion ZrO2 thin film coatings.

In this work it is shown a precise way to optimize the heat generation in high viscosity magnetic colloids, by adjusting the Néel relaxation time in core/shell bimagnetic nanoparticles, for magnetic fluid hyperthermia (MFH) applications. To pursue this goal, Fe3O4/Zn x Co1-x Fe2O4 core/shell nanoparticles were synthesized with 8.5 nm mean core diameter, encapsulated in a shell of ∼1.1 nm of thickness, where the Zn atomic ratio (Zn/(Zn + Co) at%) changes from 33 to 68 at%. The magnetic measurements are consistent with a rigid interface coupling between the core and shell phases, where the effective magnetic anisotropy systematically decreases when the Zn concentration increases, without a significant change of the saturation magnetization. Experiments of MFH of 0.1 wt% of these particles dispersed in water, in Dulbecco modified Eagles minimal essential medium, and a high viscosity butter oil, result in a large specific loss power (SLP), up to 150 W g-1, when the experiments are performed at 571 kHz and 200 Oe. The SLP was optimized adjusting the shell composition, showing a maximum for intermediate Zn concentration. This study shows a way to maximize the heat generation in viscous media like cytosol, for those biomedical applications that require smaller particle sizes.

This work presents a systematic study of the high temperature properties of BaCe0.4Zr0.4Pr0.2O3−δ perovskite in view of its potential application in proton conducting solid oxide fuel cells.

A study to determine the optimal content of Nb(V) ethoxide required to efficiently catalyze the H-2 sorption kinetics in the Mg/MgH2 system is reported. The materials were synthesized by hand mixing different amounts of additive (from 0.10 to 1 mol%) to pre-milled MgH2. Considering kinetics and capacity the best performance corresponds to a 0.25 mol % of Nb ethoxide concentration. With this material, a remarkable kinetic behavior with excellent reversibility is obtained: 5.3 wt% and 5.1 wt% of hydrogen are absorbed and desorbed respectively at 300 degrees C in 3 min. At 250 degrees C the material absorbs 5.2 wt% of hydrogen and releases 3.7 wt% in 10 min. Thermal desorption starts at 247 degrees C and peaks at 268 degrees C. The H-2 sorption properties of all the materials remain unchanged after 10 cycles of absorption and desorption at 300 degrees C, and the best material reversibly takes in and releases 5.3 wt% of H-2 during a 10 min combined cycle. The kinetic improvement of the hydrogen desorption and absorption properties is attributed to an enhancement of the kinetic processes that occur on the surface of the material, due to the excellent spreading of the liquid additive at nanometric level, as revealed by SEM/EDS and TEM/EELS. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

In this work, we studied the cation occupancy of bimagnetic CoO/Co1-xZnxFe2O4 core/shell nanoparticles by means of X-ray absorption and Mossbauer spectroscopies, which provide element-sensitive information at the atomic scale. Our results indicate that, although the spinel ferrite forms a multi-grain shell, the Zn cations occupy solely tetrahedral sites, while the Co cations are mostly in the octahedral site. On the other hand, the Fe cations are distributed in both tetrahedral and octahedral sites for all concentrations. Also the results provide evidence for a Zn-deficient spinel with an excess of Co cations in the shell, whose origin is further rationalized in terms of the two-step synthesis process. In overall, this work gives a description of the cation occupancy in the core/shell nanoparticles and can serve as a guide to the interpretation of the magnetic properties of complex bimagnetic systems for future technological applications. (C) 2021 Elsevier B.V. All rights reserved.

Here we report the development of a bifunctional magnetic nanocomposite that induces magnetic hyperthermia and shows stable paramagnetic defects after the irradiation with X-ray source. The composite is formed by Zn0.4Fe2.6O4 nanoparticles of 18 (3) nm of diameter embedded in a micrometric carbonated hydroxyapatite matrix. As the magnetic nanoparticles are fixed in the matrix, their magnetic properties were adjusted by the size and composition in order to induce local heating in presence of an AC magnetic field by the Néel mechanism. This behavior was confirmed by measuring the Specific Power Absorption (SPA) of 0.1 wt% of magnetic nanoparticles dispersed in media of different viscosity as chloroform (η=0.56 cP) and butter oil (η=174 cP) obtaining ~111(15) W/g in both cases. Consistently, the magnetic hydroxyapatite nanocomposite presents a comparable SPA=126(19) W/g value. On the other hand, the carbonated hydroxyapatite and the magnetic carbonated hydroxyapatite were subjected to X-ray radiation with an equivalent dose of 3 kGy and the generated paramagnetic defects were evaluated by electron paramagnetic resonance spectroscopy. It was observed that the CO2- radical is the main defect produced by the irradiation, and its concentration stabilized after a month. These results confirm the potential of this nanocomposite to act as a local nanoheater and sensor of ionizing radiation, showing interesting possibilities to be used in studies of nanomedicine where combining magnetic hyperthermia and radiotherapy is proposed for oncological treatments.

In this work, the synthesis and catalytic activity of bimetallic Ag–Au nanoparticles (NPs) supported in TiO2 mesoporous thin films (MTFs) are presented. The composite materials were obtained through a two‐step procedure, performed at room conditions. In the first step, Ag NPs were grown inside the MTFs by photoreduction. Then, a galvanic replacement reaction with Au was carried out, yielding the bimetallic NPs. The composites were characterized by UV/Vis spectroscopy, transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS) and X‐ray reflectometry (XRR), which show that the alloyed Ag–Au NPs are present inside the mesopores. Moreover, Ag and Au composition relationship can be controlled by adjusting the reaction times of the photoreduction and galvanic replacement reactions, respectively. Pores remain accessible after NPs synthesis, a feature that ensures their possible applications in any device that requires the contact between the NPs and the medium. Catalytic activity of the composites towards 4‐nitrophenol reduction by sodium borohydride was evaluated. Although all the bimetallic systems exhibit improved catalytic properties in comparison with the monometallic Ag composite, the sample with lower Au/Ag relationship is the most effective. For the first time, to the best of our knowledge, bimetallic Au–Ag NPs are encapsulated inside mesoporous TiO2 films, paving the way towards a wide variety of applications.

Oxides with proton conductivity have a great potential for applications in environmental energy technology. Despite the BaCe0.4Zr0.4Y0.2O3−δ (BCZY) perovskites being well-known proton conductors, i...