Electrochemical alkaline water splitting for green hydrogen production is attractive, due to its large scalability and low-cost. However, the dependence on freshwater and the severe chloride corrosion in seawater significantly hinder practical seawater electrolysis. In particular, chloride ions can induce catalyst degradation and trigger competing chlorine evolution reactions, leading to poor durability and selectivity. Moreover, the slow kinetics of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at the cathode and anode result in substantial overpotentials and energy consumption. Although noble-metal catalysts demonstrate exceptional activity, their scarce availability and prohibitive cost limit large-scale implementation. Herein, we report a chloride-shielding electrocatalyst by precisely anchoring Pt single atoms (PtSA) onto NiFe-LDH and NiMo heterostructures through an electroreduction strategy. The engineered PtSA sites modulate the local electronic structure and create a protective catalytic interface that suppresses chloride attack while promoting rapid HER and OER kinetics. As a result, the catalyst exhibits outstanding activity in natural alkaline seawater, requiring only 158 and 372 mV overpotentials to achieve 100 mA cm-2 for HER and OER, respectively. When assembled into a two-electrode water electrolyzer, the system delivers 500 mA cm-2 at only 1.64 V, outperforming most reported seawater electrolysis catalysts. This work provides an effective strategy for designing chloride-resistant catalysts for efficient and durable seawater electrolysis. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
Flexible electronics and self-powered wearable systems require fabrication platforms that simultaneously enable high-performance energy storage and harvesting on conformable substrates at industrial scale, yet no single method has consolidated these capabilities with the reproducibility demanded by practical deployment. Screen-printing addresses this gap through precise ink deposition, minimal material waste, and compatibility with polymers, textiles, and paper across roll-to-roll production formats. This review critically synthesizes progress in screen-printed supercapacitors and nanogenerators, providing unified analysis of ink engineering, electrode materials, device architectures, and integration strategies that existing reviews treat independently. Electrode materials spanning carbon systems, MXenes, transition metal oxides, conducting polymers, and hybrid nanocomposites are appraised, with the literature reporting areal capacitances up to 4979 mF/cm2, energy densities reaching 62 µWh/cm2, and cycling retention exceeding 90% after 10,000 cycles. Mechanical stability under repeated bending and substrate adhesion over extended operation are evaluated alongside electrochemical performance. Screen-printed piezoelectric, triboelectric, and pyroelectric nanogenerators, directly interfaced with printed supercapacitors in self-powered configurations, deliver output voltages reaching 103 V. Batch reproducibility and process standardization are examined as prerequisites for transitioning screen-printing from laboratory prototyping to scalable manufacturing. Machine learning-guided optimization, hybrid printing approaches, and multifunctional ink design are identified as convergent pathways toward this goal.
HfS2 is a layered semiconductor for electronic and optoelectronic applications, but humidity-assisted native oxidation limits its ambient stability. Raman spectroscopy probes HfS2 degradation but is time-consuming and condition-sensitive. Here, we revisit a previously reported HfS2 aging dataset to develop a Raman-calibrated image-based framework for rapid, non-destructive screening of CVD-grown HfS2 films on c-plane sapphire. Photographs collected under a documented configuration yielded predefined color, histogram, texture, and spatial descriptors. A simple, interpretable regression using only CIE Lab b* with physical-range clipping achieved a within-library, query-excluded leave-one-day-out RMSE of 6.78 days for 21 queries from three optically evolving conditions: native HfS2 at 35% and 70% RH and PMMA-capped HfS2 at 70% RH. The b*-based model performed comparably to kNN (7.70 days) and significantly better than a no-information pool-mean baseline (9.84 days, p = 0.0030), indicating that more complex estimators provided no clear benefit in the present dataset. Under leave-one-pair-out evaluation of 20 image-Raman pairs, the combined image-derived estimate showed a trend-level relationship with measured normalized A1g intensity (R2 = 0.600), while ΔE gave the best individual result (R2 = 0.701). The framework identified its limits: severe degradation of native HfS2 at 70% RH was underestimated, whereas Al2O3-encapsulated HfS2 showed insufficient optical evolution for reliable chronological estimation. Accordingly, this material- and configuration-specific method is a proof-of-concept screening framework, not a universal dating model or a substitute for Raman spectroscopy. Within this scope, controlled photography provides interpretable pre-screening of broad aging states and prioritizes samples for Raman or chemical analysis.
Biochars produced from sawdust (SD) and manure pellets (MP) at pyrolysis temperatures of 300, 500, and 700 °C, with and without steam activation, were evaluated for their adsorption characteristics for methylene blue (MB) and methyl orange (MO). The physicochemical characteristics and surface functionalities of the biochars, previously studied as part of a larger project, provided insights into their dye adsorption behavior in this work. Increasing the pyrolysis temperature significantly increased the surface area of SD biochars, primarily due to devolatilization and pore development, with a further increase observed under steam activation. In contrast, MP biochars exhibited no significant changes in surface area, likely due to pore blockage by ash formed from mineral components. Scanning electron microscopy (SEM) confirmed enhanced porosity at higher temperatures, and X-ray diffraction (XRD) revealed amorphous structures in SD biochars and crystalline inorganic phases in MP. Fourier-transform infrared spectroscopy (FTIR) indicated a reduction in surface functional groups with increasing pyrolysis temperature, while steam activation at 500 °C may retain sufficient surface functionalities that contribute to dye adsorption. Biochars produced at 500 °C demonstrated the highest adsorption performance, reflecting a favorable balance between surface area and functional groups. Steam activation further increased dye adsorption by improving pore accessibility and introducing more active sites. Despite having lower surface areas, MP biochars exhibited competitive adsorption, likely due to their mineral-rich surfaces contributing to dye interactions. Adsorption followed the Langmuir isotherm model and pseudo-2nd-order kinetics, indicating monolayer chemisorption on homogeneous surfaces. These findings highlight the interplay between thermal processing and feedstock composition in governing adsorption behavior, providing design strategies for an efficient biochar-based dye adsorption system for environmental remediation.
In this study, the global mean characteristics and spatial distribution differences of the Lorenz energy cycle (LEC) were investigated using four atmospheric reanalysis datasets over 44 years from 1980 to 2023. The global mean values show that the energy terms exhibit relatively small differences among the datasets, with values ranging from − 7.4 to + 3.7
