Molybdenum disulfide (MoS ₂) has emerged as a promising electrocatalyst for the electrochemical reduction of CO ₂, primarily yielding carbon monoxide. However, product selectivity is known to be highly sensitive to structural features such as edge termination and defect density. In this work, we report the formation of higher hydrocarbons (C ₂+ products) enabled by the presence of inherent sulfur vacancies in MoS ₂ when combined with various ionic liquids as co-catalysts. While MoS ₂ has traditionally shown limited hydrocarbon output, our findings demonstrate for the first time that native defect sites, interacting synergistically with the electrolyte environment, can facilitate the production of significant amounts of C ₂+ species. These results provide new insights into defect-mediated catalytic pathways and highlight the importance of electrolyte design in tuning product distribution during CO ₂ electroreduction.

Nickel coatings are widely used for corrosion and wear resistance, often undergoing post-treatment to enhance performance. Depending on their final application, Ni-coated steel may be subjected to mechanical forming processes to produce cylindrical can shapes, commonly used as battery cases or food storage containers where corrosion resistance is critical. Before mechanical forming, a key thermomechanical process called temper rolling is applied to improve coating adhesion, reduce residual stress, and minimize surface defects. This study systematically investigates the corrosion mechanisms of Ni-electroplated steel after annealing and temper rolling, demonstrating that both processes enhance localized corrosion resistance by modifying microstructure, surface morphology, and surface oxide evolution. These treatments promote passivity by increasing NiO content relative to Ni(OH)₂, significantly improving charge transfer resistance. Additionally, iron diffusion from the steel substrate generates an electrical surface potential gradient within the coating, affecting nobility variations across different regions. Post-corrosion analysis of temper-rolled samples reveals that corrosion initiation occurs at submicron grains, where structural gaps facilitate substrate exposure, underscoring the role of processing routes in enhancing coating durability.

The dream corrosion inhibitor would work for every substrate–environment combination, and the protection would be sustained indefinitely with an irreversible barrier layer when exposed to aggressive and changing environmental conditions. However our prior electrochemical experiments on AA2024-T3 have shown that despite the initial inhibition, all of the tested molecules had reversible bonds that limit their inhibition performance and applicability in dynamic environments, with the exception of 3-amino-1,2,4-triazole-5-thiol, which still showed 42% inhibition efficiency after being exposed to 0.1M NaCl only for three days. To our knowledge, this is the first mechanistic study that explains the origin of such quasi-sustained inhibition by an organic molecule under dynamic and aggressive conditions relevant to aerospace alloys. Potentiodynamic polarization, atomic force microscopy and scanning Kelvin probe force microscopy (AFM/SKPFM), X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS) complemented by density functional theory (DFT) calculations were used to identify the molecular mechanism responsible for the quasi-stable adsorption provided by 3-amino-1,2,4-triazole-5-thiol. Our findings suggest that a sulphatization of the Al-(hydr)oxide is the key contributor to the quasi-sustained corrosion inhibition. Sustained molecule adsorption over intermetallics in trace amounts was also observed, but their presence was insufficient to inhibit corrosion.

Optimizing the deposition parameters in the fabrication of passivating contacts for crystalline silicon solar cells is critical for improving efficiency. This study explored the influence of varying RF power of Plasma-Enhanced Chemical Vapor Deposition (PECVD) on the quality of hydrogenated intrinsic amorphous silicon ( a-Si:H) films. The aim is to manufacture in-situ phosphorous-doped poly-Si/SiO_x/c-Si passivating contacts with a-Si:H as buffer layer between the tunnelling oxide and the n-type poly-Si. The microstructure factor of our intrinsic layers increases from 0.176 to 0.804, that is from higher to lower film density, as the RF power increases from 5 W to 55 W. Analysis using X-ray Photoelectron Spectroscopy and Optical Microscopy indicates that the Si content in SiO_x is correlated with the formation of pinholes. Our detailed analysis showed that varying the RF power when depositing a-Si:H contacting layer is crucial in altering both the Si⁴⁺ content in SiO_x and the pinhole density, due to the interplay between the plasma etching and the buffering effects during of the a-Si:H layer growth. Notably, the sample processed with 25 W exhibited the maximum pinhole density, the lowest Si⁴⁺ content in SiO_x and the deepest phosphorus in-diffusion, potentially yielding superior results in passivation quality and contact resistivity under optimized PECVD conditions.

The search for non-toxic alternatives to hexavalent chromium based corrosion inhibitors requires a comprehensive understanding of the factors critical to effective corrosion protection. Key considerations include the evolution of corrosion inhibition with inhibitor concentrations and exposure times, the inhibition efficacy in the presence and following absence of inhibitors, and the stability of inhibition upon polarisation. In our electrochemical comparison of promising organic molecules with sodium dichromate, we found that even top-performing candidates can lead to premature conclusions if such critical factors are overlooked. While organic molecules can match the inhibition performance of chromates under specific conditions, this can be misleading when considering concentration, time, and polarisation dependent behaviour. Initial high performance can also be deceptive in dynamic environments, as we observed that the inhibition provided by most organic molecules drastically decreases when the inhibitor is absent in the electrolyte. These observations call for broader comprehensive inhibitor robustness studies that take into account factors including time, concentration, stability, and polarisation effects in inhibitor efficacy analysis.

The development of advanced catalysts with innovative nanoarchitectures is critical for addressing energy and environmental challenges such as the electrochemical CO₂ reduction reaction (CO₂ RR). Herein, the synthesis of an innovative copper–sulfur planar structure, Cu–S–BDC, within a metal–organic framework (MOF) catalyst is presented, which demonstrates 100% selectivity toward formate as the sole carbon product. Structural analysis and surface characterizations reveal that Cu–S–BDC exhibits quasi-2D inorganic building units, with Cu bonded to two S-CH (Formula presented.) groups and one BDC linker, while carboxylate groups adopt a bridging coordination mode. This unique arrangement not only imparts remarkable structural stability but also enhances the electronic properties of the MOF, as evidenced by a narrow bandgap of 1.203 eV that facilitates efficient charge transfer and increased electrochemical current density in CO (Formula presented.) RR. Notably, it offers a Faradaic efficiency of 92% for formate at an overpotential as low as −0.4 V versus the reversible hydrogen electrode (RHE) in an aqueous electrolyte of 1 m KOH, as well as a current density of −25.8 mA cm² at −0.9 V versus RHE, averaged over 24 h of electrolysis. This study highlights a fresh perspective in the field of MOF electrocatalysts by demonstrating that engineering the metal coordination environment can significantly enhance the electronic properties and consequently improve the electrocatalytic performance of these materials.

Electrochemical CO₂ reduction (CO₂R) to chemicals and fuels has made tremendous progress since the introduction of gas diffusion electrodes (GDEs) to overcome mass-transfer limitations and enable industrial-scale current densities. The advancement in the field, however, has come with new challenges that are related to the stability and degradation of the GDE due to flooding issues, which currently hinder the scale-up. Here, we investigated the effect of six different binding materials (Nafion, polytetrafluoroethylene, Fumion, Pention, poly(vinyl alcohol), and polypyrrole) on the stability and performance of Ag-based GDEs for CO₂R to CO in alkaline media. All binders show a decrease in the Faraday efficiency (FE) of CO and increase in hydrogen evolution reaction over time. The most hydrophilic GDE based on polypyrrole can uphold a higher FE of CO for longer times, which is contrary to a common belief that low wettability is required for long-term stability. By using a range of tools (SEM-EDX, SEM-FIB, X-ray diffraction, and contact angle measurements) for the postelectrolysis characterization of the GDEs, we show that the performance loss is related to flooding, bi(carbonate) precipitation, and catalyst agglomeration. These results contribute to a better understanding of the stability issues in GDE-based CO₂ electrolyzers.

XPS analysis is routinely used in corrosion studies to analyse corrosion product and protective layers on a range of metals. In the case of transition metals and especially iron, the extraction of information about chemical species including identification and quantification requires complex fitting of the metal 2p spectrum. Unfortunately, there is extensive misunderstanding of what is required for fitting of these metal 2p photoelectron peaks. In the case of high spin Fe 2p compounds there is a complex structure based on multiplet and satellite peaks which is often ignored. In this review of the application of XPS in the study of corrosion and protection of ferrous metals; we quantify the extent of misinterpretation of XPS Fe 2p spectra within the literature. It is found that in over 70 % of papers there is an adamant misunderstanding of the requirements for fitting Fe 2p, which can be divided into three groups. First, in the most serious case, there seems to be a lack of understanding of spin orbit coupling which gives rise to the major Fe 2p_3/2 and Fe 2p_1/2 peaks with the latter being incorrectly assigned to a different chemical species. Second, satellite structures are often assigned to a different chemical species. Third, single peaks are used to fit chemical components whereas a complex multiplet structure should be employed. We establish the extent to which these errors are made by critical appraisal of over 220 papers published in selected years between 2015 and 2024.

Titanium dioxide (TiO₂) has been widely used as a photocatalyst in CO₂ reduction reaction (CO₂RR) due to its low cost, high stability, and strong absorption in the close-to-visible ultra-violet (UV) range. However, TiO₂ films suffer from poor selectivity in CO₂ reduction due to their unfavorable electronic properties. In this work, we address this challenge by fabricating ultra-thin (14 nm) defective TiO₂ films (TiO₂-DTF) to enhance the selectivity of CO₂RR towards formate. TiO₂ sol was prepared using a facile and reproducible sol-gel method and directly deposited onto the surface of the electrode, forming a uniform, ultra-thin TiO₂ layers with a high number of defects. The activity of the TiO₂-DTF catalyst was studied in both photochemical and photoelectrochemical CO₂RR, indicating that the applied potential increases both the yield and selectivity of CO₂RR to formate. The TiO₂-DTF photocathode exhibited remarkable formate production during CO₂ reduction, achieving exceptional Faradaic efficiencies of up to 45 %. To elucidate the mechanism of photoelectrochemical CO₂RR on TiO₂-DTF, an in-situ attenuated total reflection Fourier-transform infrared spectroscopy (in-situ ATR-FTIR) was used and experimental results were supported by density functional theory (DFT) calculations. This study demonstrates that ultra-thin highly defective TiO₂ film, prepared using the cost-effective and environmentally friendly sol-gel method, can be used as photoelectrocatalyst for CO₂ reduction.

2D materials, characterized by their extensive surface area and customizable chemical and electronic properties, offer compelling advantages as advanced materials. These unique attributes pave the way for the development of next-generation electronics and optoelectronics, photo- and electro-catalysis, energy storage and conversion devices, and sensors. The most prominent and commonly available 2D transition metal dichalcogenide, molybdenum disulfide (MoS₂), has already shown its potential for advanced applications. However, its relatively unfavorable electronic structure and limited intrinsic conductivity lower its suitability for applications that require high conductivity, such as electrocatalysts. One way to enhance its conductivity is by electrochemically intercalating alkali metal ions, e.g., Na⁺ and K⁺, into its layered structure, potentially adjusting its electronic structure. Here, we present a comprehensive investigation into the atomic-scale intercalation mechanism using molecular dynamics simulations, complemented by experimental analysis of structural and electronic properties at the macro scale through various characterization techniques. It is demonstrated that the hydration shell of ions serves as an energy barrier to intercalation as it undergoes a structural change during the intercalation. When alkali metal ions are intercalated into MoS₂, they introduce more defects and enhance conductivity. Notably, these effects are more pronounced for potassium than for sodium.

In the search for effective high-tech materials for energy conversion and storage devices, spinel-structured nickel ferrite (NiFe₂O₄) has been identified as a promising anode material for lithium-ion batteries (LIBs). However, the influence of different morphologies and surface properties of NiFe₂O₄ nanoparticles on battery performance is hardly addressed. To understand the effect of different morphologies and surface properties on the lithium-ion storage performance, NiFe₂O₄ nanoparticles were synthesized through four different synthesis conditions: NFO-S, NFO-U, NFO-G, and NFO-C. The formation of polycrystalline inverse spinel NiFe₂O₄ was confirmed through XRD, FTIR, and Raman spectroscopy. The morphologies of the obtained samples were studied using FESEM, and it was found that the four different synthesis conditions employed here enabled us to obtain NiFe₂O₄ with four different morphologies. The surface chemistry, surface area and porosity of the NiFe₂O₄ samples were respectively characterized using XPS and BET. The electrochemical performance of the four NiFe₂O₄ samples as anode material was studied by fabricating lithium-ion half-cells. NiFe₂O₄ sample obtained from surfactant-free synthesis condition (NFO-S) displayed a high initial discharge and charge capacity of 2258 mAh/g and 1815 mAh/g, respectively at the current density of 100 mA/g. Even after 100 cycles, NFO-S showed a better discharge capacity of 116 mAh/g at the current density of 100 mA/g, compared to the other samples studied here. The observed higher capacity of the NFO-S sample is attributed to the higher surface area (40.8 m²/g) and pore volume (0.190 cm³/g). The NiFe₂O₄ sample prepared with cationic CTAB surfactant (NFO-C) showed better cyclic stability with a stable coulombic efficiency of 98.5% at the 100th cycle, mainly attributed to its nanocube morphology with lower surface area (16.1 m²/g) and pore volume (0.087 cm³/g).

We present a mechanically robust, cost-effective, and scalable ultra-superhydrophobic ceramic-polymer composite coating featuring a hierarchical micro/nano-structured surface. This advanced coating, fabricated via a single-step process, integrates alumina (Al₂O₃) and zirconia (ZrO₂) to harness their individual and synergistic effects, achieving an extreme water contact angle of 180° and a sliding angle of 1°. The coating demonstrates strong adhesion and compatibility with a wide range of substrates, including aluminum and concrete. The Al₂O₃–ZrO₂-based composite exhibits outstanding physicochemical properties, including ultra-superhydrophobicity, anti-icing, anti-corrosion, and anti-vapor condensation capabilities. It also maintains excellent non-wetting behavior across a variety of liquids. Comprehensive surface analyses, encompassing microstructural, morphological, and chemical characterization, underscore the critical role of hierarchical structuring and tailored surface chemistry in enhancing functionality. Mechanical durability assessments reveal that the coating retains its superhydrophobic performance even after extensive scratching test. Moreover, it exhibits self-cleaning, anti-adhesion, and anti-fouling characteristics, attributed to its engineered surface texture and the synergistic contributions of Al₂O₃–ZrO₂ heterojunctions and oxide-silane bonding (Si–O–Si and Si–OH). This multifunctional ceramic-polymer coating addresses key challenges in large-scale deployment by offering a streamlined, scalable fabrication method and versatile performance, positioning it as a promising solution for diverse industrial applications.

The inherent colloidal dispersity (due to length, aspect ratio, surface charge heterogeneity) of CNCs, when produced using the typical traditional sulfuric acid hydrolysis route, presents a great challenge when interpreting colloidal properties and linking the CNC film nanostructure to the helicoidal self-assembly mechanism during drying. Indeed, further improvement of this CNC preparation route is required to yield films with better control over the CNC pitch and optical properties. Here we present a modified CNC-preparation protocol, by fractionating and harvesting CNCs with different average surface charges, rod lengths, aspect ratios, already during the centrifugation steps after hydrolysis. This enables faster CNC fractionation, because it is performed in a high ionic strength aqueous medium. By comparing dry films from the three CNC fractions, discrepancies in the CNC self-assembly and structural colors were clearly observed. Conclusively, we demonstrate a fast protocol to harvest different populations of CNCs, that enable tailored refinement of structural colors in CNC films.