Articles publicats en revistes (Física Aplicada)

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PENGEOM -- A general-purpose geometry package for Monte Carlosimulation of radiation transport in complex material structures (NewVersion Announcement)
(Elsevier B.V., 2025-04-18) Almansa, Julio; Salvat Pujol, Francesc; Díaz-Londoño, Gloria; Carnicer González, Arturo; Lallena, Antonio M.; Salvat Gavaldà, Francesc
A new version of the code system pengeom, which provides a complete set of tools to handle different geometries in Monte Carlo simulations of radiation transport, is presented. The distribution package consists of a set of Fortran subroutines and a Java graphical user interface that allows building and debugging the geometry-definition file, and producing images of the geometry in two- and three dimensions. A detailed description of these tools is given in the original paper [Comput. Phys. Commun. 199 (2016) 102–113] and in the code manual included in the distribution package. The present new version differs from the previous one in that 1) it implements a more systematic handling of round-off errors, 2) the set of examples has been updated, and 3) it allows including a single voxelized box as a geometry module. With the last optional feature, a Monte Carlo code can readily be used for describing irradiation processes with complex material structures, such as medical treatments.
MXenes: Multifunctional 2D materials for hydrogen evolution, energy storage, and carbon capture applications
(Elsevier B.V., 2025-11-01) Serafin, Jarosław; Chaitoglou, Stefanos; Farid, Ghulam; Ma, Y.; Dziejarski, Bartosz; Sánchez Niubò, Albert; Vendrell, Xavier; Amade Rovira, Roger
Ti₃C₂Tₓ MXene was synthesized by selective etching of Ti₃AlC₂ MAX phase using HF. Structural and surface properties were assessed via XRD, Raman, SEM, HRTEM, BET, and XPS, confirming Al removal, interlayer expansion, and functionalization with single bondF, –OH, and = O groups. The resulting MXene exhibited a specific surface area of 26.7 m2/g and pore size of 16.2 nm. A single batch was deployed in three applications: as an HER electrocatalyst in 1 M H₂SO₄, achieving −511 mV onset potential, 190 mA cm−2 at −760 mV, and a Tafel slope of 184 mV dec−1; as a supercapacitor electrode in 3 M KOH, with areal capacitance of 411.1 mF cm−2 and 86.9 % diffusion-controlled contribution; as a CO₂ adsorbent, achieving uptakes of 0.80 and 0.66 mmol g−1 at 0 °C and 25 °C, respectively. Adsorption data fitted best to the Radke–Prausnitz isotherm, indicating mixed physisorption–chemisorption. A techno-economic analysis yielded a production cost of ~2.83 €/g. These results demonstrate the multifunctionality and scalability of Ti₃C₂Tₓ MXene as a good material for hydrogen generation, energy storage, and carbon capture.
Intercomparison of H SAF and IMERG heavy rainfall retrievals over a Mediterranean coastal region
(Elsevier B.V., 2026-01-01) Peinó, Eric; Petracca, M.; Polls, Francesc; Udina Sistach, Mireia; Bech i Borràs, Jaume
Satellite-based precipitation products play a crucial role in providing global, continuous, and reliable estimates of rainfall, essential for understanding and managing Earth’s water cycle. This study evaluates the accuracy of three H SAF satellite products (H61B, H64, and H68) and compares their performance with IMERG V06B (Early and Late Runs) products in detecting and estimating extreme precipitation events in the western Mediterranean region. The analysis is based on hourly and daily rainfall data collected from 186 rain gauges in Catalonia (NE Iberian Peninsula), using a point-to-pixel approach. The results show that satellite estimates tend to overestimate low precipitation accumulations (less than 2 mm and 10 mm in one hour and one day respectively), with this overestimation being more evident in the H68 product at the hourly scale and in IMERG Late at the daily scale. However, all products show a substantial decline in accuracy for higher precipitation amounts, particularly when they exceed 10 mm in one hour and 30 mm in one day (relative errors up to −60% and critical success index less than 33% in all cases). Despite its biases, IMERG Late product emerged as the most reliable for detecting substantial rainfall accumulations. Additionally, this analysis examined the relationship between the microphysical properties of the precipitating cloud top and estimated or observed surface precipitation. Accurate precipitation estimates from the satellite products were consistently associated with high values of Cloud Optical Thickness (COT) and Ice Water Path (IWP), while false alarms were often linked to low values of these variables. As expected, the results indicated a poorer performance in estimating precipitation associated with warm clouds. Additionally, these findings highlight the importance of integrating cloud optical and microphysical properties into retrieval algorithms to improve satellite precipitation estimates.
Western Mediterranean flash floods through the Lens of Alcanar (NE Iberian Peninsula): Meteorological drivers and trends
(Elsevier B.V., 2025-11-01) Llasat Botija, María del Carmen; Marcos Matamoros, Raül; Pascual Berghaenel, Ramón; Rigo, Tomeu; Insúa Costa, Damián; Crespo Otero, Alfredo
Flash floods in the Western Mediterranean pose a growing hazard due to the effects of climate change, rapid urbanization, and land-use changes. This study focuses on flash floods in the Montsià region of southern Catalonia (NE Iberian Peninsula), with particular emphasis on the municipality of Alcanar, because it illustrates the recent intensification of flash flood dynamics in the Western Mediterranean. The research is motivated by three recent severe flood events in Alcanar (2018, 2021, and 2023), each characterized by extraordinary rainfall totals and significant economic losses, unprecedented in the municipality's 30-year observational record. Methodologically, we integrate multiple data sources—including meteorological station observations, weather radar products, lightning detection networks, high-resolution mesoscale model outputs, and a flood database spanning 1980–2023, complemented by economic compensation records from 1996 to 2020. Through this approach we (i) assess the regional frequency of heavy rainfall and flood episodes, (ii) quantify the economic impacts in Alcanar, (iii) characterize the meteorological and thermodynamic conditions on the three most intense recent events (including moisture source tracking via a Lagrangian methodology), and (iv) analyze spatio-temporal trends in extreme rainfall indicators (percentiles, threshold exceedances, kurtosis, and skewness). Our findings suggest that, from a meteorological perspective, current flash flood behavior in the Western Mediterranean likely emerges from the interplay of localized orographic triggers, elevated sea surface temperatures, strong instability associated with low-level moisture, particular positioning of jet streaks, synoptic-scale cut-off lows, and remote moisture sources. The results also point to an increase in rainfall intensity, explained by the presence of high precipitable water content and shallow convection, which enhances precipitation efficiency. These insights highlight the critical need for robust flood early warning systems, strategic watershed management, and improved risk communication to mitigate escalating flash flood risks in the Montsià county and similar areas throughout the Western Mediterranean region.
Sea surface temperature updating impacts on WRF simulations during a heatwave period
(Elsevier B.V., 2025-05-15) Busquets de Jover, Eulàlia; Udina Sistach, Mireia; Bech i Borràs, Jaume; Mercader Carbó, Jordi
This study investigates the effects of sea surface temperature (SST) updating strategy in the Weather Research and Forecasting (WRF) model during a heatwave event over the Northwestern Mediterranean Sea in July 2019. The MM5 revised Surface Layer and Yonsei University Planetary Boundary Layer (PBL) schemes were used and wind field at 10 m, air potential temperature, surface fluxes, and planetary boundary layer height were examined. Generally, the greatest impacts over the sea were observed within 20 km of the shoreline. We found an underestimation of the modeled SST in non-updated SST simulations during the heatwave episode that was propagated into the atmosphere, leading to a cold bias of 2-m potential temperature up to 2.5 K onshore. In heatwave conditions the most common surface layer stability class was very unstable, and its frequency increased when the SST was updated, particularly near the coast, revealing that SST updating leads to greater dominance of thermal turbulent mixing of surface fluxes in the heatwave period studied. Sensible and latent heat fluxes across stability regimes were analyzed, and latent heat flux showed greater sensitivity to SST updating and the highest magnitudes. However, PBL height variations between SST-updated and non-updated simulations presented a greater sensitivity to sensible heat flux. On average, during the heatwave period, the planetary boundary layer height in simulations with updated SST increased by 75 m onshore, compared to a smaller increase of 26 m offshore, which highlights the greater sensitivity in the onshore region and their impact on vertical modeled profiles. These results emphasize the importance of an accurate representation of boundary layer conditions on numerical weather prediction models, as well as illustrating the nonlinear behavior on the surface layer and PBL scheme, particularly important under heatwaves.
Electromagnetic optics theory of light at the isotropic interface: illustrating the behavior of the electric field
(European Optical Society, 2025-04-08) Bosch i Puig, Salvador; Arteaga Barriel, Oriol
The electromagnetic behavior of light at the interface between isotropic materials is governed by the Fresnel formulas. These formulas primarily describe the electric field and are straightforward to interpret when dealing with transparent materials and incidence angles below the critical angle. However, when the incidence angle exceeds the critical angle or when the transmitted wave propagates through an absorbing medium, the mathematical description becomes more complex, and the physical behavior appears less intuitive. The aim of this work is to clarify these challenging scenarios at the undergraduate and graduate level by providing a practical mathematical formulation complemented by insightful graphical illustrations. We believe this work may also be a valuable resource for researchers and professionals. Therefore, for completeness, the mathematical treatment of inhomogeneous plane waves – often necessary for the second medium – is provided in Appendix.
Extraordinary 2021 snowstorm in Spain reveals critical threshold response to anthropogenic climate change
(2024-06-20) Insua-Costa, Damián; Lemus I Canovas, Marc; González-Alemán, Juan J.; Senande-Rivera, Martín; Llasat Botija, María del Carmen; Miguez-Macho, Gonzalo; Miralles, Diego G.
Attribution of extreme weather events to anthropogenic climate change (ACC) has become an increasingly important line of research in recent years. However, the potential influence of ACC on heavy snowstorms remains largely unexplored. Here we focus on studying the exceptional January 2021 snowfall event in Spain, known as Filomena. First, using observational data and flow analogs, we show that the characteristic synoptic pattern leading to the episode has not significantly changed in frequency over the past decades. Based on this, we assume a fixed dynamical pattern and focus on studying the influence of ACC on the thermodynamics of the event using an atmospheric model and a storyline attribution approach. Our simulations indicate that in northern highlands, ACC intensified snowfall by up to +40% compared with pre-industrial conditions, while in nearby southern lowlands ACC weakened snowfall by up to –80%. This characteristic shift from weakening to intensification is well defined by a critical threshold in temperature. Furthermore, we show that if Filomena were to occur at the end of the 21st century, this contrasting response to ACC would be enhanced. Altogether, our findings highlight the large but uneven impact of global warming on extreme snowstorm events.
Robust calibration method for polarization cameras integrated with chromatic retarders
(Optical Society of America, 2025-07-28) Li, Huihui; Bian, Subiao; Arteaga Barriel, Oriol
Polarization cameras provide a compact and efficient solution for real-time polarization imaging but suffer from chromatic calibration errors when used in combination with wavelength-dependent optical components such as linear retarders. In this work, we introduce an analytical calibration method specifically designed for polarization cameras integrating chromatic retarders, which can be used both in monochromatic and color sensors. This method algebraically accounts for spectral averaging and depolarization effects arising from wavelength-dependent retardance, enabling robust and accurate polarization calibration across different spectral channels. The approach is experimentally validated using a commercial color polarization camera (FLIR Blackfly S) with integrated RGB Bayer filters and micro-polarizers, along with broadband illumination sources. Experimental results demonstrate that the effective spectral parameters, such as the effective wavelength and spectral bandwidth obtained by our calibration method, are close to theoretical predictions.
A simple pathway for complete polarization vision
(Nature Publishing Group, 2025-03-14) Bian, Subiao; Arteaga Barriel, Oriol
This paper introduces a novel method for achieving complete polarization vision through a full-Stokes polarization camera. Our technique employs a homogeneous dispersive retarder placed before a polarization sensor to harness wavelength-dependent retardation, enabling the differentiation of polarization states across the sensor’s color channels. Assuming weak wavelength dependence of polarization for incoming light, this method facilitates the real-time, simultaneous measurement of the complete Stokes vector of incident light. This method provides a streamlined, versatile, and practical solution with broad potential applications in imaging, remote sensing, and augmented reality.
Supercapacitive performance of electrodes based on defective ZnO nanorods anchored on graphene nanowalls
(Elsevier B.V., 2024-04-09) Ma, Y.; Chaitoglou, Stefanos; Farid, Ghulam; Amade Rovira, Roger; Ospina, Rogelio; Muñoz Rosas, Ana Luz; Bertrán Serra, Enric
Vertical graphene nanowalls (GNWs) have emerged as a highly promising architectural structure, offering a vast surface area teeming with active sites and expediting ion diffusion. In our relentless pursuit of bolstering their specific capacitance, we unveil a groundbreaking supercapacitive augmentation, incorporating defect-engineered ZnO nanorods (ZNRs) branching out from the GNWs. The realization of this hierarchical structure is achieved through a meticulous multi-step process, featuring inductively coupled plasma-chemical vapor deposition, magnetron sputtering, and hydrothermal synthesis. The presence of oxygen vacancy (OV) defects within the ZNRs, induced by argon annealing, has been characterized using X-ray photoelectron spectroscopy (XPS). The emergence of OV defects below the conduction band of the ZNRs results in a narrowing of the bandgap within the hybrid structure, thereby enhancing its conductivity and increasing the reaction sites. The capacity of the ZNRs/GNWs hybrid electrodes were evaluated in an aqueous KOH electrolyte solution, operating within a voltage range of 0.5 V and at a current density of 0.1 mA cm−2. This assessment yielded an area capacitance of 21.45 mF cm−2, signifying a 1.5-fold increase in capacitance compared to GNWs grown on graphite sheets. The ZNRs/GNWs hybrid demonstrates remarkable electrochemical performance and exhibits substantial potential for energy storage applications. Our work is expected to offer valuable insights for the enhancement of electrochemical properties in various composite and hybrid materials.
Optimizing energy storage: Carbon implantation in NiO matrix unveils C–NiO's hybrid capacitive and battery-like behavior with enhanced electrochemical performance
(Elsevier B.V., 2024-03-19) Shafique, Muhammad Ahsan; Farid, Ghulam; Shaheen, Fozia; Zaheer, Zeeshan; Murtaza, Ghulam; Sharif, Sadia; Ahmad, Riaz
Doping is a common strategy employed to enhance material properties. Numerous researchers have introduced carbon into the nickel oxide (NiO) matrix through various methods to improve the electrochemical performance for energy storage applications. This study investigates the impact of carbon implantation into the NiO matrix using a particle accelerator. Cyclic voltammetry profiles of carbon-implanted NiO (C–NiO) reveal distinct oxidation–reduction peaks, and one side of the CV curves exhibits a rectangular shape, confirming the hybrid capacitive and battery-like behavior of C–NiO. The reduced separation between oxidation–reduction peaks and the increased specific capacitance at higher scan rates validate the capacitive nature of C–NiO. Enhanced electrochemical performance was further explored through GCD, EIS, and BET techniques. C–NiO demonstrates impressive capacitance retention of 93.8 % after 5000 cycles. The Nyquist plot indicates that the improved performance of C–NiO is attributed to its heightened electrode activity, resulting from lower charge-transfer resistance. BET analysis confirms that C-doping leads to a larger surface area. In the NiO matrix, two bands of adsorbed CO2 are observed, whereas these bands are absent in C–NiO, indicating clearer pathways for ion–electron exchange. Compared to undoped NiO (55 F/g at 50 mV/s), C–NiO exhibits a more than tenfold increase in specific capacitance (1079 F/g at 50 mV/s).
Mueller matrix imaging with a polarization camera: application to microscopy
(Optical Society of America, 2021-10-11) Gottlieb, Dale; Arteaga Barriel, Oriol
In this work, we describe the design and implementation of a Mueller matrix imaging polarimeter that uses a polarization camera as a detector. This camera simultaneously measures the first three Stokes components, allowing for the top three rows of the Mueller matrix to be determined after only N = 4 measurements using a single rotating compensator, which is sufficient to fully characterize nondepolarizing samples. This setup provides the polarimetric analysis with micrometric resolution in about 3 seconds and can also perform live birefringence imaging at the camera frame rate by fixing the compensator at a static 45° angle. To further improve the conditioning of the setup, we also give the first experimental demonstration of an optimal elliptical retarder design.
Tailoring polycarbonate surfaces for improved Ge film adhesion: The role of plasma treatments in 50:50 O2/Ar atmospheres
(Elsevier, 2024-06) Peralta, J.; Esteve Pujol, Joan; Lousa Rodríguez, Arturo
Polycarbonate (PC) substrates were exposed to plasma environments consisting of a 50:50 mixture of oxygen and argon, and were subsequently coated with germanium (Ge) films grown via sputtering. The hydrophilicity of the PC surfaces was tailored by ion bombardment with energy levels ranging from 50 to 300 eV, which led to a reduction in water contact angles from a native 80° to a superhydrophilic state. Analyses of chemical composition and structure of the PC were performed using X-ray Spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy in Attenuated Total Reflectance geometry (FTIR-ATR), and then correlated to the adhesion of the Ge thin films. Optimal adhesion of the Ge films was achieved by bombarding the PC with ions at energies between 100 and 200 eV, activating the polymer surface while avoiding photodegradation as confirmed by chemical analysis. We report an efficient method for achieving superhydrophilicity of PC within a short treatment time of 60 s that can be effectively integrated in diverse vacuum applications.
Exploring the Limits and Balancing Efficiency, Transparency, and Esthetics in Ultrathin a-Si:H Transparent Photovoltaic Devices
(Wiley-VCH, 2025-01-08) Álvarez Suárez, Gustavo; López García, Alex; Estarlich, Pau; Asensi López, José Miguel; Masmitjà, Gerard; Ortega, Pablo; Voz Sánchez, Cristóbal; Puigdollers i González, Joaquim; Pérez Rodríguez, Alejandro
Transparent photovoltaic (TPV) devices represent a promising advance in photovoltaic technologies, particularly in building-integrated photovoltaics (BIPV). Unlike conventional photovoltaics, which primarily prioritize efficiency, TPV must balance between efficiency, transparency, and aesthetics. These additional dimensions introduce unique challenges on device architecture. This article reports the development of wide-bandgap, inorganic-based TPV devices integrating ultrathin hydrogenated amorphous silicon (a-Si:H) as a transparent absorber, with carrier selective contacts and transparent electrodes. The article analyzes how absorber thickness influences the electrical, optical, and aesthetic performance of devices, evaluating key parameters in TPV such as light utilization efficiency (LUE), average photopic transmittance (APT), color rendering index (CRI), and electrical properties such as power conversion efficiency (PCE). The device structure is SLG/FTO/AZO/a-SiCx(n)/ a-Si:H/V2Ox/AZO. This approach results in PCE ranging from 1.7% with an APT of 60% to a PCE of 4.1% with an APT of 28%, yielding LUE values between 0.9% and 1.3%. Device characterization encompasses optical spectrophotometry, J–V measurements under standard test conditions, spectral response analysis, and variable illumination measurements (VIM). Additionally, color characterization is conducted using CIE 1931 color space maps to determine the chromaticity coordinates, CRI, and the variation of color as a function of absorber thickness.
Vertical graphene nanowalls supported hybrid W2C/WOxcomposite material as an efficient non-noble metal electrocatalystfor hydrogen evolution
(Elsevier, 2024-05-17) Rodriguez Miguel, Shahadev; Ma, Y.; Farid, Ghulam; Amade Rovira, Roger; Ospina, Rogelio; Andújar Bella, José Luis; Bertrán Serra, Enric; Chaitoglou, Stefanos
Research for the development of noble metal-free electrodes for hydrogen evolution has blossomed in recent years. Transition metal carbides compounds, such as W2C, have been considered as a promising alternative to replace Pt-family metals as electrocatalysts towards hydrogen evolution reaction (HER). Moreover, hybridization of TMCs with graphene nanostructures has emerged as a reliable strategy for the preparation of compounds with high surface to volume ratio and abundant active sites. The present study focuses in the preparation of tungsten carbide/oxide compounds deposited in a three-dimensional vertical graphene nanowalls (VGNW) substrate via chemical vapor deposition, magnetron sputtering and thermal annealing processes. Structural and chemical characterization reveals the partial carburization and oxidation of the W film sputtered on the VGNWs, due to C and O migration from VGNWs towards W during the high temperature annealing process. Electrochemical characterization shows the enhanced performance of the nanostructured hybrid W2C/WOx on VGNW compound towards HER, when compared with planar W2C/WOx films. The W2C/WOx nanoparticles on VGNWs require an overpotential of -252 mV for the generation of 10 mA cm-2. Chronoamperometry tests in high overpotentials reveal the compounds stability while sustaining high currents, in the order of hundreds of mA. Postchronoamperometry test XPS characterization unveils the formation of a W hydroxide layer which favours hydrogen evolution in acidic electrolytes. We aspire that the presented insights can be valuable for those working on the preparation of hybrid electrodes for electrochemical processes.
Tropical Atlantic variability in EC-EARTH: impact of the radiative forcing
(Springer Verlag, 2024-04-04) Volpi, Danila; García-Serrano, Javier, 1980-; Palmeiro, Froila M.; Gil Reyes, Laura; Haarsma, Reindert J.
Understanding the impact of radiative forcing on climate variability and change in the Tropical Atlantic is crucial for different socio-economic sectors, given their substantial impacts in both local and remote regions. To properly evaluate the effect of a changing climate on the variability, the use of standard transient historical and scenario simulations requires very large ensembles. A computationally cheaper alternative implemented in this study consists of performing two 250-year-long atmosphere-ocean coupled simulations with EC-EARTH 3.3 (CMIP6 version) with fixed radiative forcing at the years 2000 and 2050, representative of present and future climate conditions, respectively. The changes in the leading modes of Tropical Atlantic variability (TAV), including the Atlantic Niño/Niña and the Subtropical North Atlantic pattern, have been assessed in three target seasons: spring (MAM), summer (JJ) and early winter (ND). While the change in sea surface temperature (SST) climatology shows homogeneous warming, the difference between future and present SST variability exhibits a distinct behaviour consistent along the seasonal cycle, with a decrease in the equatorial region and an increase at subtropical latitudes. This study explores the processes associated with the suppressed/enhanced TAV, with a particular focus on the less-explored early winter season. In agreement with previous studies, the Atlantic Meridional Overturning Circulation (AMOC) shows a weakening in strength, but the results also show an increase in variability. The AMOC-related deepening of the equatorial thermocline and the flattening linked to weakened trade winds are consistent with the suppressed SST variability of the Atlantic Niño/Niña. On the other hand, the enhanced SST variability at subtropical latitudes is mainly associated with an increase in turbulent heat flux variability, with a minor contribution of the mixed layer depth variability. Variability in turbulent heat flux is influenced primarily by latent heat flux, connected to changes in precipitation variability.
Depth-sensitive instrument for Mueller matrix imaging measurements
(Elsevier B.V., 2025-11-24) Pardo, Iago; Kuntman, Ertan; Ossikovski, Razvigor; Pascual Miralles, Esther; Arteaga Barriel, Oriol
We present an optical imaging approach that combines Spatial Frequency Domain Imaging (SFDI) and MuellerMatrix Imaging (MMI) to enable depth-resolved characterization of polarization properties in turbid media. Bysimultaneously exploiting the spatial selectivity of SFDI and the sensitivity of Mueller polarimetry to microstructuralanisotropy, our method provides complementary contrast mechanisms that reflect both the layered structureand polarization-dependent behaviour of complex samples. Spatially modulated illumination at multiple frequenciesis used to control the sampling depth, while full Mueller matrix measurements are performed at eachfrequency to capture the evolution of polarization as a function of depth. Experimental results in phantoms andbiological tissue demonstrate the potential of this dual-mode technique to distinguish subsurface polarizationfeatures that would otherwise remain obscured in conventional imaging. This integrated approach opens new possibilitiesfor applications requiring non-invasive, depth-sensitive analysis of anisotropic or scattering structures,such as biomedical diagnostics or material characterization.
Revolutionizing energy storage: Silicon nanowires (SiNWs) crafted throughmetal-assisted chemical etching
(King Saud University, 2024-01-17) Farid, Ghulam; Amade Rovira, Roger; Ma, Y.; Chaitoglou, Stefanos; Ospina, Rogelio; Bertrán Serra, Enric
In the world of advanced energy conversion and storage, silicon nanostructures have garnered immense interestof scientists and innovators alike with their unique structural, electrical, optical and electrochemical properties,setting the stage for a brighter, more sustainable future. Amidst the array of top-down methods, one methodstands out as an approach-change: Metal-assisted chemical etching (MacEtch). It is highlighted for its cost-effectiveness, simplicity, versatility and scalability, making it a crucial point in the world of micro/nano Sistructure fabrication. Recent breakthroughs have propelled MacEtch into the limelight, making it the go-totechnique for crafting micro/nano structures with exceptional electrochemical attributes. These structures aretailor-made for energy storage applications, from lithium-ion batteries (LIBs) to supercapacitors. Join us in thiscaptivating feature article as we unveil the mechanism underlying the MacEtch’s silicon transformation. Explorethe latest and old strides achieved in the field of Silicon nanowires (SiNWs) generated through MacEtch,particularly in the context of their electrochemical properties for energy storage applications.
Exploring the role of national weather services in climate change knowledge and communication: an international survey
(Springer, 2024-10-11) Molina, Tomàs, 1963-; Abadal, Ernest
This study investigates the roles, perspectives, and communication strategies of National Meteorological Services (NMS) concerning climate monitoring, climate change projections, and the attribution of meteorological phenomena to climate variations. Using a survey distributed to 131 of the 193 National Meteorological Services affiliated with the World Meteorological Organization, we explore how these entities contribute to and communicate about the science of climate change. The survey targeted their involvement in observing and recording climate data, making climate projections, attributing specific weather events to climate change, and their methods of communicating these issues to the public and government officials. Responses were received from 44 countries, reflecting diverse levels of economic development and capabilities in handling, and disseminating complex climate information. The results show a strong engagement in traditional meteorological tasks, with a varied approach to the scientific study of climate change effects and public communication strategies. This study highlights the critical role of NMS in climate change research and underscores the challenges they face in effectively communicating complex climate information, which is crucial for public understanding and policymaking.
Laser-Induced Vertical Graphene Nanosheets for Electrocatalytic Hydrogen Evolution
(2024-09-25) Chaitoglou, Stefanos; Ma, Yang; Ospina, Rogelio; Farid, Ghulam; Serafin, Jarosław; Amade Rovira, Roger; Bertrán Serra, Enric
Efficient and affordable electrocatalysts are fundamental for the sustainable production of hydrogen from water electrolysis. Here, an approach for the rapid production of laserinduced vertical graphene nanosheets (LIVGNs) through the exfoliation of the graphite foil under laser irradiation is presented.The density of the formed LIVGNs is ∼3 per 100 μm2. On leveraging the inherent flexibility and conductivity of the graphite foil substrate, the resulting LIVGNs exhibit a 2.2-fold increase incapacitance, making them promising candidates for electrode applications. The laser-induced surface reconstruction introduces abundant sharp edges to the LIVGNs, enhancing their electrocatalyticpotential for hydrogen evolution. In electrocatalytic hydrogen evolution tests in acidic media, the LIVGNs demonstrate superior performance with a remarkable decrease in the required overpotential at 10 mA cm−2, from −555 mV for the pristine graphite foil to −348 mV for LIVGNs. This improvement is attributed to the active sites provided by the sharp edges, facilitating hydrogen species adsorption. Furthermore, the hydrophilic behavior of LIVGNs is enhanced through the anchoring of oxygencontaining groups, promoting the rapid release of the produced hydrogen bubbles. Importantly, the modified LIVGN electrode exhibits long-term stability across a wide range of current densities during chronoamperometry tests. This research introduces a transformative strategy for the efficient preparation of vertical graphene sheets on conductive graphite foils, showcasing their potential applications in electrocatalysis and energy storage.

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