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Electrodeposited amorphous hydrated iridium oxide (IrOx) is a promising material for pH sensing due to its high sensitivity and the ease of fabrication. However, durability and variability continue to restrict the sensors effectiveness. Variation in probe films can be seen in both performance and fabrication, but it has been found that performance variation can be controlled with potentiostatic conditioning (PC). To make proper use of this technique, the morphological and chemical changes affecting the conditioning process must be understood. Here, a thorough study of this material, after undergoing PC in a pH-sensing-relevant potential regime, was conducted by voltammetry, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Fitting of XPS data was performed, guided by raw trends in survey scans, core orbitals, and valence spectra, both XPS and UPS. The findings indicate that the PC process can repeatably control and conform performance and surface bonding to desired calibrations and distributions, respectively; PC was able to reduce sensitivity and offset ranges to as low as ±0.7 mV/pH and ±0.008 V, respectively, and repeat bonding distributions over ~2 months of sample preparation. Both Ir/O atomic ratios (shifting from 4:1 to over 4.5:1) and fitted components assigned hydroxide or oxide states based on the literature (low-voltage spectra being almost entirely with suggested hydroxide components, and high-voltage spectra almost entirely with suggested oxide components) trend across the polarization range. Self-consistent valence, core orbital, and survey quantitative trends point to a likely mechanism of ligand conversion from hydroxide to oxide, suggesting that the conditioning process enforces specific state mixtures that include both theoretical Ir(III) and Ir(IV) species, and raising the conditioning potential alters the surface species from an assumed mixture of Ir species to more oxidized Ir species.

Thiamine hydrochloride (TH) acts as a highly efficient additive to traditional ZnSO 4 electrolyte, which combines zincophilic groups and polar groups, in situ reconfiguring the anode/electrolyte interface based on interfacial coordination chemistry, thus enhancing the electroplating/stripping reversibility of Zn metal anodes. [Display omitted] The highly reversible electrochemical deposition and dissolution of zinc metal anode is a critical feature for the practical application of aqueous zinc-ion batteries (ZIBs). Nevertheless, this process is seriously hindered by the uncontrollable electrodeposition and interfacial side reactions caused by thermodynamically unstable anode/electrolyte interface (AEI). Guided by the electrode/electrolyte interface chemistry, thiamine hydrochloride (TH) as a novel additive is added into traditional ZnSO 4 (ZS) electrolyte to induce sustained reversible Zn deposition/stripping. Spectroscopic characterizations and electrochemical tests reveal that TH can adsorbed on the anode surface owning to the strong double-coordination effect between N, S atoms and Zn atoms via Zn-N and Zn-S chemical bonds. In addition, there are polar hydroxyl groups in the TH molecular structure which can form hydrogen bonds with water molecules. Thus, the adsorbed TH layer can not only guide the diffusion of Zn2+ ions and achieve dendrite-free electrodeposition process, but also prevent intimate contact between water and anode to suppress the occurrence of interface side reactions. Based on these benefits, the TH additive achieves an ultra-long stable cycle lifespan to 2045 h at 1 mA cm−2 and 1 mAh cm−2. Even at a higher current density of 5 mA cm−2, prolonged cycling performance about 773 h is demonstrated. Besides, the assembled Zn//NVO full cells reveal excellent capacity retention and rate performance under practical conditions, highlighting the efficient and reliable coordination effect of TH additive at the AEI. [ABSTRACT FROM AUTHOR]

Monitoring hexanal gas at parts per billion (ppb) levels is significantly challenging. Among sensing materials, MXenes with abundant active sites, controllable surface chemistry, and tunable conductivity have shown particular promise in gas sensing of hexanal gas, but pure MXenes still suffer from low sensitivity and baseline drift. Herein, p-type metal oxide Pd-doped-CuO adhering to surfaces and interlayers of the Ti 3 C 2 T x was fabricated to yield sensing platforms. The formation of p-p heterojunctions enhanced the responses of Pd-doped-CuO/Ti 3 C 2 T x gas sensor toward detection of hexanal at 150 °C by more than 3.2-fold when compared to pure Ti 3 C 2 T x. The nanocomposite sensor also exhibited an ultra-low detection limit of 0.1 ppm, faster response-recovery time (19/40 s), and good stability (30 days) for trace hexanal detection. The improved gas-sensing mechanism based on the formation of p-p heterojunctions, sufficient reactive centers provided by CuO, and promoted catalytic ability of PdO. [ABSTRACT FROM AUTHOR]

The ionic liquid-integrated aqueous electrolyte was designed to remodel the interfacial electrical double layer with simultaneously manipulating solvation chemistry and adsorption situation on the Zn anode, which facilitates the Zn(H 2 O) 6 2+ desolvation process and Zn ion flux, thus enabling an excellent Zn plating/stripping cycling stability with negligible by-products and Zn-dendrites. [Display omitted] Zn anodes suffer from poor reversibility and stability owing to nonuniform dendrite growth and self-corrosion. Here, 1-ethyl-3-methylimidazolium acetate (EMImAc) is introduced to reconstruct interfacial electrical double layer with simultaneously manipulating the solvation environment and the adsorption situation on Zn anode. The acetate anions with high nucleophilicity can effectively alter the solvation shell around Zn2+ ions and immobilize the H 2 O molecules, thus weakening water activity and alleviating water-related parasitic reactions. Concomitantly, both the imidazolium cation and acetate anion are inclined to gather on Zn anode surface for constructing an electrostatic shielding layer, and meanwhile the chemisorbed acetate anions also contribute to accelerate the Zn(H 2 O) 6 2+ desolvation process. Such a synergistic effect enables uniform electric field distribution and facilitates Zn ion flux, which mitigates the random diffusion of Zn2+ and finally promotes the dendrite-free deposition. As a result, the Zn/Zn symmetric cells with EMImAc-integrated aqueous electrolyte realize an excellent cycling lifespan of 7000 h (0.5 mA cm−2/0.25 mAh cm−2) and high Zn utilization of 61.3 % (15 mA cm−2/20 mAh cm−2). Furthermore, the effective of EMImAc additive is demonstrated in Zn/V 2 O 5 cells. This work offers insights into the ionic liquid-integrated aqueous electrolytes to enhance the interface stability of Zn anode for rechargeable zinc batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Novel carbon xerogels doped with heteroatoms (O, N, S) were prepared by sol–gel polymerization of resorcinol with heterocyclic aldehydes containing them. All doped materials presented higher O-contents than the reference material prepared with formaldehyde, and significant S- or N-loadings in the corresponding samples. Carbon xerogels were micro-mesoporous and N-doping favoured the formation of mesopores. Their efficiency in the dynamic ethylene adsorption is presented as an interplay between porosity, surface chemistry and humidity. The surface hydrophilicity was also studied by water adsorption assays, a quick adsorption being favoured in microporous samples with hydrophilic O-groups. Breakthrough curves for ethylene adsorption were recorded in both dry and humid conditions and analysed according to the mass transference zone (MTZ). The material behaviour was correlated with the physicochemical properties, elucitating the mechanism of the simultaneous water/ethylene adsorption. The adsorption capacity depended linearly on the microporous characteristics of samples; however, MTZ parameters (efficiency of the column) varied linearly with the electronegativity of the dopant element. Both doping and humidity in the stream hindered the ethylene adsorption kinetic and capacity (up to 33% for N-doped material under humidity compared to undoped-material under dry conditions), due to reduced adsorbate-adsorbent interactions and the accessibility into narrow pores. [ABSTRACT FROM AUTHOR]

Through a large parameter space, electric fields can tune colloidal interactions and forces leading to diverse static and dynamical structures. So far, however, field-driven interactions have been limited to dipole-dipole and hydrodynamic contributions. Nonetheless, in this work, we propose that under the right conditions, electric fields can also induce interactions based on local chemical fields and diffusiophoretic flows. Herein, we present a strategy to generate and measure 3D chemical gradients under electric fields. In this approach, faradaic reactions at electrodes induce global pH gradients that drive long-range transport through electrodiffusiophoresis. Simultaneously, the electric field induces local pH gradients by driving the particle's double layer far from equilibrium. As a result, while global pH gradients lead to 2D focusing away from electrodes, local pH gradients induce aggregation in the third dimension. Evidence points to a mechanism of interaction based on diffusiophoresis. Interparticle interactions display a strong dependence on surface chemistry, zeta potential and diameter of particles. Furthermore, pH gradients can be readily tuned by adjusting the voltage and frequency of the electric field. For large Péclet numbers, we observed a collective chemotactic-like collapse of particles. Remarkably, such collapse occurs without reactions at a particle's surface. By mixing particles with different sizes, we also demonstrate, through experiments and Brownian dynamics simulations, the emergence of non-reciprocal interactions, where small particles are more drawn towards large ones.   [ABSTRACT FROM AUTHOR]

A sequential self‐polymerization of phenolic compounds combined with alkanedithiol (ADT) crosslinkers is developed as a versatile surface‐independent coating and functionalization strategy. The resulting copolymer takes advantage of the diverse binding modes of catechol and gallol and the conformal substrate contact facilitated by the flexible aliphatic chain of ADT. Moreover, Michael addition and thiyl radical addition reactions between ADT and phenolic compounds produce crosslinked resulting polymer films, rendering solvent resistance to the surface coating. This approach is successfully employed using phenolic monomers, including dopamine, 3,4‐dihydroxybenzylamine, 4‐ethylcatechol, levodopa, tannic acid, caffeic acid, and 3,4‐dihydroxybenzylaldehyde, to functionalize glass (ceramic), aluminum (metal), polyethylene (polymer), and Teflon surfaces. The resulting copolymer prepared with a trifunctional thiol crosslinker demonstrated solvent resistance in NaOH (aq.), DMSO, and chloroform, overcoming the stability issues typically encountered by conventional surface coating from polydopamine derivatives. [ABSTRACT FROM AUTHOR]

Decoupling certain material surface properties can be key to attaining critical property‐activity relationships that underpin their antibiofouling performance. Here, orthogonal nano‐engineering (ONE) is employed to decouple the influences of nanotopography and surface chemistry on surface antibiofouling. Nanotopography and surface chemistry are systematically varied with a two‐step process. Controlled nanotopography is obtained by electrochemical anodization of aluminum, which generated anodic aluminum oxide (AAO) surfaces with cylindrical nanopores (diameters: 15, 25, and 100 nm). To modify surface chemistry while preserving nanotopography, an ultrathin (≈5 nm) yet stable zwitterionic coating of poly(divinylbenzene‐4‐vinylpyridyl sulfobetaine) is deposited on these surfaces using initiated chemical vapor deposition (iCVD). Antibiofouling performance is assessed by quantifying 48‐h biomass formed by gram positive and negative bacteria. The ONE surfaces demonstrated enhanced antibiofouling performance, with small‐pore nanotopography and zwitterionic chemistry each lowered biomass accumulation by tested species, with potential additive effects. The most effective chemistry‐topography combination (ZW‐AAO15) enabled an overall reduction of 91% for Escherichia coli, 76% for Staphylococcus epidermidis, 69% for Listeria monocytogenes, and 67% for Staphylococcus aureus, relative to the uncoated nanosmooth control. Additionally, the composite ZW coating exhibited encouraging anticorrosion properties under both static and turbulent cleaning conditions, vital to antibiofouling applications in healthcare and food industries. [ABSTRACT FROM AUTHOR]

Patterning of various surface properties, including roughness, wettability, adhesiveness, and mechanical properties, can markedly enhance the functionality of test systems. Thus, porous polymethacrylates prepared by polymerization‐induced phase separation (PIPS) represent a promising class of functional materials for the construction of miniaturized test systems. Different porosity, surface chemistry, and wettability are achieved in porous polymethacrylates with different precursor compositions. Nevertheless, only wettability microstructuring has been highlighted for these materials thus far. Here, the study presents a novel method for the direct and selective deposition of porous polymethacrylate films with different surface chemistry and porosity. The selective adhesion of omniphobic–omniphilic wettability patterns is used to facilitate the polymer pattern formation. The feasibility of patterning with different monomers and porogenic solvents is demonstrated. The topological study confirms the selective application of polymer structures with different thickness and roughness. The wettability characterization of the omniphobic material shows no significant changes caused by the operations performed. Thus, a new pattern with a greater difference in the wettability of the areas is produced in the process. Discontinuous dewetting of different liquids is performed. The use of poly(2‐hydroxyethyl methacrylate‐co‐ethylene dimethacrylate) (HEMA‐EDMA) modified patterns for precise living cell patterning is also demonstrated. [ABSTRACT FROM AUTHOR]

The low-cost small molecule nicotinamide serves as an electrolyte additive for aqueous zinc-ion batteries. Only 1 wt% of nicotinamide enables Zn||Zn symmetric cells to have an ultra-long lifespan of over 9700h at 1 mA cm−2, expanding nearly 808 times compared to that without nicotinamide. This work is remarkable among state-of-the-art novel aqueous zinc-ion batteries. [Display omitted] Aqueous zinc-ion batteries (AZIBs) have recently been paid great attention due to their robust safety features, high theoretical capacity, and eco-friendliness, yet their practical application is hindered by the serious dendrite formation and side reactions of Zn metal anode during cycling. Herein, a low-cost small molecule, nicotinamide (NIC), is proposed as an electrolyte additive to effectively regulate the Zn interface, achieving a highly reversible and stable zinc anode without dendrites. NIC molecules not only modify the Zn2+ solvation structure but also preferentially adsorb on the Zn surface than solvated H 2 O to protect the Zn anode and provide numerous nucleation sites for Zn2+ to homogenize Zn deposition. Consequently, the addition of 1 wt% NIC enables Zn||Zn symmetric cells an ultra-long lifespan of over 9700 h at 1 mA cm−2, which expands nearly 808 times compared to that without NIC. The advantages of NIC additives are further demonstrated in NaVO||Zn full cells, which exhibit exceptional capacity retention of 90.3 % after 1000 cycles with a high Coulombic efficiency of 99.9 % at 1 A/g, while the cell operates for only 42 cycles without NIC additive. This strategy presents a promising approach to solving the anode problem, fostering advancements in practical AZIBs. [ABSTRACT FROM AUTHOR]

Nucleic-acid biosensors have emerged as useful tools for on-farm detection of foodborne pathogens on fresh produce. Such tools are specifically designed to be user-friendly so that a producer can operate them with minimal training and in a few simple steps. However, one challenge in the deployment of these biosensors is delivering precise sample volumes to the biosensor's reaction sites. To address this challenge, we developed an innovative drop dispenser using advanced 3D printing technology, combined with a hydrophilic surface chemistry treatment. This dispenser enables the generation of precise sample drops, containing DNA or bacterial samples, in volumes as small as a few micro-liters (∼20 to ∼33 μL). The drop generator was tested over an extended period to assess its durability and usability over time. The results indicated that the drop dispensers have a shelf life of approximately one month. In addition, the device was rigorously validated for nucleic acid testing, specifically by using loop-mediated isothermal amplification (LAMP) for the detection of Escherichia coli O157, a prevalent foodborne pathogen. To simulate real-world conditions, we tested the drop dispensers by integrating them into an on-farm sample collection system, ensuring they deliver samples accurately and consistently for nucleic acid testing in the field. Our results demonstrated similar performance to commercial pipettors in LAMP assays, with a limit of detection of 7.8×106 cells/mL for whole-cell detection. This combination of precision, ease of use, and durability make our drop dispenser a promising tool for enhancing the effectiveness of nucleic acid biosensors in the field. [ABSTRACT FROM AUTHOR]

pH sensing technology is pivotal for monitoring aquatic ecosystems and diagnosing human health conditions. Indium–gallium–zinc oxide electrolyte-gated thin-film transistors (IGZO EGTFTs) are highly regarded as ion-sensing devices due to the pH-dependent surface chemistry of their sensing membranes. However, applying EGTFT-based pH sensors in complex biofluids containing diverse charged species poses challenges due to ion interference and inherently low sensitivity constrained by the Nernst limit. Here, we propose a dual-biased (DB) EGTFT pH sensing platform, acquiring back-gate-assisted sensitivity enhancement and recyclable redox-coupled protonation at the semiconductor-biofluid interface. A solution-processed amorphous IGZO film, used as the proton-sensitive membrane, ensures scalable uniformity across a 6-inch wafer. These devices demonstrate exceptional pH resistivity over several hours when submerged in solutions with pH levels of 4 and 8. In-depth electrochemical investigations reveal that back-gate bias significantly enhances sensitivity beyond the Nernst limit, reaching 85 mV/pH. This improvement is due to additional charge accumulation in the channel, which expands the sensing window. As a proof of concept, we observe consistent variations in threshold voltage during repeated pH cycles, not only in standard solutions but also in physiological electrolytes such as phosphate-buffered saline (PBS) and artificial urine, confirming the potential for reliable operation in complex biological environments. [ABSTRACT FROM AUTHOR]

Magnetic activated carbon has been proved its separation ability to overcome a main drawback of activated carbon powder. However, effect of magnetization method on characterizations and Chromium (VI) adsorption of this adsorbent from Artocarpus Heterophyllus Peel (jackfruit peel) has not been investigated yet. This study magnetized jackfruit peel activated carbon using thermochemical and co-precipitation methods. Magnetic jackfruit activated carbon (MJAC) were examined and compared to jackfruit activated carbon (JAC) for surface chemistry, texture, morphology and crystalline properties. The isotherm/kinetics of Cr(VI) adsorption on these adsorbents were also analyzed. The results showed that all the adsorbents showed a typical peak of –(COO)n–Fe of iron oxide particles and functional groups but the adsorbent prepared with thermochemical method had the greatest Fe–O–C bond signal. The thermochemical adsorbent also had various particles of Fe3O4, Zero Valent Iron, and α-Fe2O3 while the co-precipitation absorbents gave a greater mesoporous structure and specific surface area than their JAC precursor; especially the adsorbent produced at mild temperature was covered by the highest iron oxide distribution on the surface and better magnetite property. As a result of the high specific surface area, these co-precipitation adsorbents were more effective for Cr(VI) adsorption than others. The PSO model best describes Cr(VI) adsorption on all absorbents with and without magnetite. Cr(VI) adsorption on JAC was dominated by intra-particle diffusion while multistep processes, including external mass transfer, governed the overall MJAC adsorption process. This work has created jackfruit peel-based magnetic activated carbon for wastewater treatment to remove toxic heavy metals and promote the circular economy that uses solid wastes as raw materials. Highlights: The first investigation of magnetic jackfruit peel-based activated carbon for Cr(VI) removal application. Physico-chemical properties and Cr(VI) adsorption of magnetite absorbents affected by magnetization methods of thermochemical and co-precipitation A strong attraction of iron oxide particles with carbon and various types of iron particles were observed in thermochemical adsorbent whereas the development of mesoporous structure and specific surface area were found in co-precipitation adsorbent [ABSTRACT FROM AUTHOR]

The application of upconversion nanoparticles (UCNPs) for cell and tissue analysis requires a comprehensive understanding of their interactions with biological entities to prevent toxicity or harmful effects. Whereas most studies focus on cancer cells, this work addresses non-cancerous cells with their regular in vitro physiology. Since it is generally accepted that surface chemistry largely determines biocompatibility in general and uptake of nanomaterials in particular, two bilayer surface coatings with different surface shielding properties have been studied: (i) a phospholipid bilayer membrane (PLM) and (ii) an amphiphilic polymer (AP). Both surface modifications are applied to (12–33) nm core-shell UCNPs NaYF4(Yb, Er)@NaYF4, ensuring colloidal stability in biological media. The impact of UCNPs@AP and UCNPs@PLM on non-cancerous epithelial-like kidney cells in vitro was found to differ significantly. UCNPs@PLM did not exhibit any measurable effect on cell physiology, even with prolonged exposure. In contrast, UCNPs@AP caused changes in cell morphology and induced cell-death after approximately 30 h. These variations in toxicity are attributed to the distinct chemical stability of these particles, which likely influences their intracellular disintegration. [ABSTRACT FROM AUTHOR]

Ovarian cancer (OC) must be detected in its early stages when the mortality rate is the lowest to provide patients with the best chance of survival. Lysophosphatidic acid (LPA) is a critical OC biomarker since its levels are elevated across all stages and increase with disease progression. This paper presents an LPA assay based on a thickness shear mode acoustic sensor with dissipation monitoring that involves a new thiol molecule 3-(2-mercaptoethanoxy)propanoic acid (HS-MEG-COOH). HS-MEG-COOH is an antifouling linker that provides (a) antifouling properties for gold substrates and (b) linking ability via its terminal carboxylic acid functional group. The antifouling ability of HS-MEG-COOH was tested in whole human serum. The new molecule was applied to the LPA assay in conjunction with a spacer molecule, 2-(2-mercaptoethoxy)ethan-1-ol (HS-MEG-OH), in a 1:1 v/v ratio. HS-MEG-COOH was covalently linked to gelsolin–actin, a protein complex probe that dissociates due to LPA-binding. LPA was detected in phosphate-buffered saline and undiluted human serum and achieved a low limit of detection (1.0 and 0.7 μM, respectively) which was below the concentration of LPA in healthy individuals. The antifouling properties of HS-MEG-COOH and the detection of LPA demonstrate the ability of the sensor to successfully identify the early-stage OC biomarker in undiluted human serum. [ABSTRACT FROM AUTHOR]

This review addresses the effects of various decontamination methods on the wettability of titanium and zirconia dental implants. Despite extensive research on surface wettability, there is still a significant gap in understanding how different decontamination techniques impact the inherent wettability of these surfaces. Although the literature presents inconsistent findings on the efficacy of decontamination methods such as lasers, air-polishing, UV light, and chemical treatments, the reviewed studies suggest that decontamination alters in vitro hydrophilicity. Post-decontamination surface chemistry must be carefully considered when selecting optimal surface treatments for implant materials. Further in vitro investigations are essential to determine which approaches best enhance surface wettability, potentially leading to improved implant–tissue interactions in clinical settings. [ABSTRACT FROM AUTHOR]

We have developed a novel ternary nanocomposite comprising of nitrogen-doped carbon quantum dots@α-Fe2O3/PANI (N-CQDs@α-Fe2O3/PANI nanocomposite) and use it as an active electrode material for supercapatteries. Doped carbon nanostructures-based nanocomposites are excellent candidates for electrochemical energy storage due to their tunability in the surface chemistry and availability of large electrochemical surface area. Initially, N-CQDs@α-Fe2O3 nanocomposite was synthesized and further insitu polymerization of aniline leads to the formation of N-CQDs@α-Fe2O3/PANI nanocomposite. The N-CQDs@α-Fe2O3 serves as a substrate to accommodate PANI to enhance the electrochemical activity. The specific capacity of the ternary nanocomposite electrode is 149 C g−1 (with a corresponding specific capacitance of 372.5 F g−1) at a current density of 1 A g−1 in a 2 M KOH (aqueous) electrolyte with a coulombic efficiency of 99% after 3000 cycles. Hence, it is proposed that the N-CQDs@α-Fe2O3/PANI nanocomposite has been suitable for the ideal electrode material which has potential application in hybrid energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Förster resonance energy transfer (FRET) serves as a critical mechanism to study intermolecular interactions and the formation of macromolecular assemblies. Cascade FRET is a multi-step FRET process which can overcome limitations associated with traditional single-step FRET. Herein, a novel organic–inorganic hybrid composed of a nile red derivative attached to the edge of the layered silicate clay Laponite (Lap-NR) was used to facilitate cascade FRET between Laponite sheets. Utilizing naphthalene-diimide edge-modified Laponite (Lap-NDI) as the initial donor, Rhodamine 6G on the basal surface of Laponite as the first acceptor, and Lap-NR as the second acceptor, cascade FRET was achieved. The influence of solvent composition in a DMF/water mixture on cascade FRET was investigated, revealing that a higher water content led to an enhancement of the cascade FRET process, which is attributed to increased aggregation-induced emission of Lap-NDI and the enhanced quantum yield of R6G in water. This study provides a unique approach to achieve cascade FRET by taking advantage of the anisotropic surface chemistry of a two-dimensional nanomaterial, providing a colloidally-driven alternative with improved tunability compared to macromolecular routes. The flexibility and simplicity of this approach will advance the state of the art of organic–inorganic hybrids for applications in optoelectronics, sensors, and hybrid photovoltaics. [ABSTRACT FROM AUTHOR]

Due to the surface‐dominant nature of electrokinetic ion transport in confined geometries, ionic currents in nanofluidic channels are fundamentally governed by the interfacial chemistry of the constituent substrates. In this work, the intrinsic coupling between charge‐regulated oxide surfaces and local changes in concentration and pH induced during the operation of bipolar nanofluidic diodes is numerically explored. Using a heterogeneous SiO2‐Al2O3 nanochannel as a representative example, field‐dependent ion accumulation and depletion effects are shown to have a marked effect on the local surface chemistry and resulting charge density of the amphoteric Al2O3 surface in particular. While the SiO2 surface tends to remain relatively indifferent to the presence of an applied potential due to its low point of zero charge (PZC), the comparatively high PZC of Al2O3 renders it much more susceptible to the extent of ion accumulation and depletion events which drive localized concentration and pH changes. Including this surface coupling in models can be necessary to capture the true behavior of real‐world devices; comparison with a fixed‐charge model demonstrates that only a fully coupled model can quantitatively reproduce reported experimental current measurements in heterogeneous SiO2‐Al2O3 nanochannels, the limiting behavior of which is revealed to stem from this surface‐to‐bulk coupling. [ABSTRACT FROM AUTHOR]

As society moves away from heavy industry, large metallic structures will be abandoned. As an alternative to dismantling, these structures could be repurposed. Beyond being a practical solution, the conservation of these structures would serve as an ode to the role of these industries in shaping modern society. Conservation, however, requires suitable coatings that hinder corrosion long-term while not significantly altering the outward appearance. Traditionally, the stability of coatings has been tested by comparing fresh samples to those aged naturally or in a UV chamber. This method of testing provides no temporal information. Additionally, measuring many different conditions, e.g., UV, humidity, temperature, and pollutants, is tedious. In this review, we highlight how by implementing infrared spectroscopy in different configurations, temporally resolved information about the coating chemistry, the metal–coating interface chemistry, and gas emissions could be gained during degradation. These insights would be essential to enable the intentional design of coatings while simultaneously revealing their environmental impact. [ABSTRACT FROM AUTHOR]

We report the results of a zinc oxide (ZnO) low-power microsensor for sub-ppm detection of NO2 and H2S in air at 200 °C. NO2 emission is predominantly produced by the combustion processes of fossil fuels, while coal-fired power plants are the main emitter of H2S. Fossil fuels (oil, natural gas, and coal) combined contained 74% of USA energy production in 2023. It is foreseeable that the energy industry will utilize fossil-based fuels more in the ensuing decades despite the severe climate crises. Precise NO2 and H2S sensors will contribute to reducing the detrimental effect of the hazardous emission gases, in addition to the optimization of the combustion processes for higher output. The fossil fuel industry and solid-oxide fuel cells (SOFCs) are exceptional examples of energy conversion–production technologies that will profit from advances in H2S and NO2 sensors. Porosity and surface activity of metal oxide semiconductor (MOS)-based sensors are both vital for sensing at low temperatures. Oxygen vacancies ( V O • • ) act as surface active sites for target gases, while porosity enables target gases to come in contact with a larger MOS area for sensing. We were able to create an open porosity network throughout the ZnO microstructure and simultaneously achieve an abundance of oxygen vacancies by using a heat treatment procedure. Surface chemistry and oxygen vacancy content in ZnO were examined using XPS and AES. SEM was used to understand the morphology of the unique characteristics of distinctive grain growth during heat treatment. Electrical resistivity measurements were completed. The valance band was examined by UPS. The Engineered Porosity approach allowed the entire ZnO to act as an open surface together with the creation of abundant oxygen vacancies ( V O • • ). NO2 detection is challenging since both oxygen (O2) and NO2 are oxidizing gases, and they coexist in combustion environments. Engineered porosity ZnO microsensor detected sub-ppm NO2 under O2 interference, which affects mimicking realistic sensor operation conditions. Engineered porosity ZnO performed better than the previous literature findings for H2S and NO2 detection. The exceptionally high sensor response is attributed to the high number of oxygen vacancies ( V O • • ) and porosity extending through the thickness of the ZnO with a high degree of tortuosity. These features enhance gas adsorption and diffusion via porosity, leading to high sensor response. [ABSTRACT FROM AUTHOR]

Ionic liquid ion sources (ILIS) have been proposed as a source of alternative ion chemistries for surface etching, focused ion beams, and secondary ion mass spectrometry. These ion sources produce polydisperse ion beams containing several solvated ion species with a distribution of energies, and it is necessary to filter the ion beam to obtain monoenergetic beams with a single ion chemistry as required by nanomanufacturing and analytical applications. In this work, a Wien filter has been designed, built, and tested for use with an ILIS using the liquid 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate, or EMI-FAP. comsol multiphysics simulations have been used to validate the design. The full and unfiltered ion beams have been characterized using time-of-flight mass spectrometry and retarding potential analysis, and these measurements confirm that the filter is effective in isolating monomer ions from heavier ion species in the beam. [ABSTRACT FROM AUTHOR]

The unique structural properties of porous ceramics, such as low thermal conductivity, high surface area, controlled permeability, and low density, make this material valuable for a wide range of applications. Its uses include insulation, catalyst carriers, filters, bio-scaffolds for tissue engineering, and composite manufacturing. However, existing processing methods for porous ceramics, namely replica techniques and sacrificial templates, are complex, release harmful gases, have limited microstructure control, and are expensive. In contrast, the direct foaming method offers a simple and cost-effective approach. By modifying the surface chemistry of ceramic particles in a colloidal suspension, the hydrophilic particles are transformed into hydrophobic ones using surfactants. This method produces porous ceramics with interconnected pores, creating a hierarchical structure that is suitable for applications like nano-filters. This review emphasizes the importance of interconnected porosity in developing advanced ceramic materials with tailored properties for various applications. Interconnected pores play a vital role in facilitating mass transport, improving mechanical properties, and enabling fluid or gas infiltration. This level of porosity control allows for the customization of ceramic materials for specific purposes, including filtration, catalysis, energy storage, and biomaterials. [ABSTRACT FROM AUTHOR]

Post-processing, and particularly the dry electropolishing process, is essential for improving the surface quality of 3D-printed Ti6Al4V samples, with specific emphasis on reducing roughness over extended polishing times while preserving mechanical properties. Reducing surface roughness enhances the reliability of hardness measurements and improves the consistency of elastic modulus measurements, as prolonged polishing time stabilizes the full width at half maximum values, thereby minimizing variability due to uniaxial indentation. This stability is crucial for maintaining the structural integrity and uniformity of mechanical properties, facilitating better performance and reliability in biomedical applications. Additionally, under service-like working conditions, solid electrolyte particles undergo dehydration due to the Joule effect, introducing a dynamic aspect to the system as the particle structure degrades with thermal cycling. EDX cross-sectional analysis reveals that TiO2 informs the particle's surface, with an oxygen-to-titanium ratio that confirms the oxide's composition. This TiO2 oxide layer demonstrates the progressive surface oxidation occurring under the post-processing process, further modifying the particle's surface chemistry. This dual effect of roughness reduction and controlled surface chemistry highlights the role of dry electropolishing in enhancing the functional lifespan and mechanical reliability of Ti6Al4V components. [ABSTRACT FROM AUTHOR]

Nanoparticle surfactants (NPSs) that form via the reversible non‐covalent interactions between nanoparticles (NPs) and polymer ligands at the oil‐water interface have received great attention in constructing structured liquids with unique stimuli‐responsiveness. Introducing dynamic covalent interactions to generate NPSs is expected to achieve a balance between high mechanical strength and dynamic responsiveness of the interfacial assemblies. Here, we present the formation, assembly, and jamming of a new type of NPS by the co‐assembly between polydopamine NPs (PDA NPs) and poly(styrene‐co‐methacrylamidophenylboronic acid) at the oil‐water interface. Dynamic covalent boronate ester bonds form in situ at the interface and show multiple responsiveness when applying stimuli such as pH, H2O2, and temperature, allowing the controlled assembly/jamming of NPSs and reconfiguration of liquid constructs. Due to the photothermal property of PDA NPs, the temperature responsiveness of boronate ester bonds can also be triggered by irradiating the biphasic system with near‐infrared (NIR) light. Moreover, when bringing two droplets encapsulated with NPSs into contact and irradiating the contact area by NIR, thermal welding of droplets can be realized, offering a straightforward to construct droplet networks and modular liquid devices. [ABSTRACT FROM AUTHOR]

The increased clinical application of cell‐based therapies has resulted in a parallel increase in the need for non‐invasive imaging‐based approaches for cell tracking, often through labeling with nanoparticles. An ideal nanoparticle for such applications must be biologically compatible as well as readily internalized by cells to ensure adequate and stable cell loading. Surface coatings have been used to make nanoparticle trackers suitable for these purposes, but those currently employed tend to have cytotoxic effects. Zwitterionic ligands are known to be biocompatible and antifouling; however, head‐to‐head evaluation of specific zwitterionic ligands for cell loading has not yet been explored. Magnetic particle imaging (MPI) detects superparamagnetic iron oxide nanoparticles (SPIONs) using time‐varying magnetic fields. Because MPI can produce high‐contrast, real‐time images with no tissue depth limitation, it is an ideal candidate for in vivo cell tracking. In this work, we have conjugated hard (permanently charged) and soft (pKa‐dependently charged) biomimetic zwitterionic ligands to SPIONs and characterized how these ligands changed SPION physicochemical properties. We have evaluated cellular uptake and subcellular localization between zwitterions, how the improvement in cell uptake generated stronger MPI signal for smaller numbers of cells, and how these cells can be tracked in an animal model with greater sensitivity for longer periods of time. Our best‐performing surface coating afforded high cell loading within 4 h, with full signal retention in vivo over 7 days. [ABSTRACT FROM AUTHOR]

Over the past few years, nanoplasmonic biosensors have gained widespread interest for early diagnosis of diseases thanks to their simple design, low detection limit down to the biomolecule level, high sensitivity to even small molecules, cost-effectiveness, and potential for miniaturization, to name but a few benefits. These intrinsic natures of the technology make it the perfect solution for compact and portable designs that combine sampling, analysis, and measurement into a miniaturized chip. This review summarizes applications, theoretical modeling, and research on portable nanoplasmonic biosensor designs. In order to develop portable designs, three basic components have been miniaturized: light sources, plasmonic chips, and photodetectors. There are five types of portable designs: portable SPR, miniaturized components, flexible, wearable SERS-based, and microfluidic. The latter design also reduces diffusion times and allows small amounts of samples to be delivered near plasmonic chips. The properties of nanomaterials and nanostructures are also discussed, which have improved biosensor performance metrics. Researchers have also made progress in improving the reproducibility of these biosensors, which is a major obstacle to their commercialization. Furthermore, future trends will focus on enhancing performance metrics, optimizing biorecognition, addressing practical constraints, considering surface chemistry, and employing emerging technologies. In the foreseeable future, these trends will be merged to result in portable nanoplasmonic biosensors offering detection of even a single biomolecule. [ABSTRACT FROM AUTHOR]

Self-assembled non-covalent nanoparticle-polymer hybrids, that can combine a variety of desired properties in a single material with highly dynamic structure, have great potential in the field of functional nanosystems. In this study, we present a method for preparing such hybrids from silica nanoparticles and polymer structures of polystyrene-block-polyacrylic acid (PS-b-PAA). We show that the surface chemistry of the nanoparticles has a major influence on the encapsulation efficiency and the localization of the particles in the vesicles. Furthermore, an increase in vesicle size was observed with higher vesicle loading. A particular highlight of this work is that the morphology of the hybrids could be subsequently modified by adjusting the solvent composition. It was also found that the presence of the particles led to faster transitions due to the increased free energy of the system. This type of morphological change therefore offers promising potential applications, such as self-healing materials. [ABSTRACT FROM AUTHOR]

The search for alternatives to Pb‐based perovskites, due to concerns about stability and toxicity, has led to the exploration of Pb‐free options. Tin (Sn) and bismuth (Bi) are promising candidates, given their similar ionic radii to Pb and the isoelectronic nature of Pb2+ and Bi3+, which suggest comparable chemical properties. Among these, CsSnBr3 and Cs3Bi2Br9 are relatively underexplored but offer lower toxicity and enhanced stability while demonstrating optoelectronic properties suitable for various applications. In this study, CsSnBr3 and Cs3Bi2Br9 nanocrystals are synthesized using a colloidal method and integrated into Schottky diodes. X‐ray photoelectron spectroscopy analysis of the surface chemistry confirms improved thermal and phase stability compared to Pb‐based perovskites. Schottky diode parameters, including ideality factor, barrier height, and series resistance are assessed using conventional thermionic emission, modified Cheung's, and Norde's models. The Cs3Bi2Br9‐based Schottky diode exhibits superior electrical performance with the lowest series resistance and optimal barrier height. Electrical impedance spectroscopy results indicated that CsSnBr3 has higher resistances and lower capacitances than Cs3Bi2Br9, reflecting lower charge carrier mobility and more defects, although the R1C1 regions in both materials demonstrated faster charge dynamics, making them ideal for high‐speed applications. [ABSTRACT FROM AUTHOR]

Nanomaterials with enzyme-like properties are known as 'nanozymes'. Nanozymes are preferred over natural enzymes due to their nanoscale characteristics and ease of tailoring of their physicochemical properties such as size, structure, composition, surface chemistry, crystal planes, oxygen vacancy, and surface valence state. Interestingly, nanozymes can be precisely controlled to improve their catalytic ability, stability, and specificity which is unattainable by natural enzymes. Therefore, tailor-made nanozymes are being favored over natural enzymes for a range of potential applications and better prospects. In this context, metal oxide nanoparticles with nanozyme-mimicking characteristics are exclusively being used in biomedical sectors and opening new avenues for future nanomedicine. Realising the importance of this emerging area, here, we discuss the mechanistic actions of metal oxide nanozymes along with their key characteristics which affect their enzymatic actions. Further, in this critical review, the recent progress towards the development of point-of-care (POC) diagnostic devices, cancer therapy, drug delivery, advanced antimicrobials/antibiofilm, dental caries, neurodegenerative diseases, and wound healing potential of metal oxide nanozymes is deliberated. The advantages of employing metal oxide nanozymes, their potential limitations in terms of nanotoxicity, and possible prospects for biomedical applications are also discussed with future recommendations. [ABSTRACT FROM AUTHOR]

This study explores the effects of atomic-level factors on the performance of CeO 2 when interacting with SiO 2 films. It specifically examines how different precursors, the ratio of Ce to OH, and reaction temperatures influence outcomes. Our findings reveal that smaller particles, around 5 nm in size, created using a Ce4+ precursor, are more effective at removing SiO 2 films compared to larger, more crystalline particles from a Ce3+ precursor. This is due to their increased interaction with the SiO 2 film during the polishing process, challenging the conventional emphasis on mechanical abrasion in chemical mechanical planarization (CMP) and highlighting the crucial role of chemical interactions. Further analysis through FT-IR and TGA-FTIR techniques showed distinct functional group profiles on the ceria surfaces. Ceria derived from Ce4+ exhibited a higher presence of OH and NO 3 groups, enhancing adsorption capabilities, as verified by CHN analysis. Importantly, first-principles calculations identified these surface groups as key to improving adhesion to SiO 2 films. Surfaces of amorphous CeO 2 , rich in -OH and -NO 3 groups, showed significantly higher adhesion levels than their crystalline counterparts, connecting crystallinity to chemical functionality. This new insight leads to the possibility of designing next-generation CeO 2 abrasives with increased chemical activity. [ABSTRACT FROM AUTHOR]

The commercial use of Si3N4 ceramics in the biomedical field dates back to the early 1980s and, initially, did not show promising results, which is why their biocompatibility was not then investigated further until about 10 years later. Over the years, a change in trend has been observed; more and more studies have shown that this material could possess high biocompatibility and antibacterial properties. However, the relevant literature struggles to find mechanisms that can incontrovertibly explain the reasons behind the biological activity of Si3N4. The proposed mechanisms are often pure hypotheses or are not substantiated by comprehensive analyses. This review begins by studying the early references to the biological activity of Si3N4 and then reviews the literature regarding the bioactivity of this ceramic over time. An examination of the early insights into surface chemistry and biocompatibility lays the foundation for a detailed examination of the chemical reactions that Si3N4 undergoes in biological environments. Next, the analysis focuses on the mechanisms of bioactivity and antipathogenicity that the material exhibits both alone and in combination with modern bioglass. However, it is highlighted that despite the general consensus on the biocompatibility and bioactivity of Si3N4 ceramics, sometimes the proposed biological mechanisms behind its behavior are discordant or unsupported by the direct evaluation of specific biochemical activities. This review highlights both the reliable information in the literature and the gaps in research that need to be filled in order to fully understand the reasons behind the biological properties of this material. [ABSTRACT FROM AUTHOR]

The study successfully enabled the creation of ceramic surfaces with multi functionalities, including superhydrophilicity, self-cleaning, antibacterial properties, and photocatalytic activity, by applying a glaze composition rich in nano ZnO/Cu–ZnO and utilizing surface chemistry and unique texturing on porcelain tiles. The tiles, coated with unique glaze compositions, were fired in an industrial furnace and heat treated. The crystalline phases and surface morphology of glazed surfaces were systematically evaluated using XRD, SEM, FT-IR, drop shape analyzer, and surface roughness profilometer. Key-factors affecting the wettability, self-clean ability, photocatalytic activity and antibacterial efficacy were discussed. Adding nano Cu into the glaze mixture that is rich in ZnO improves the evolution of zincite crystals, increases the specific surface energy, decreases surface roughness, provide superhydrophilicity and promotes the antibacterial effectiveness and photocatalytic activity. Superhydrophilic surfaces doped with nano Cu–ZnO display antibacterial characteristics that do not require UV or visible light. The quick achievement of complete self-cleaning, up to 100 %, is due to the presence of nano Cu particles in its structure. Hydrophilicity has the ability to improve the efficiency of photocatalysis. If a surface exhibits superhydrophilic properties, it shows exceptional photocatalytic performance. A surface that is solely photohydrophilic may not maintain self-cleaning. Hydrophilicity may be more important than photocatalysis in the self-cleaning effect. [ABSTRACT FROM AUTHOR]

A novel cobalt-free, high-nickel cathode material, named 0.01B-LiNi 0.98 Mg 0.01 Zr 0.01 O 2 (NMZB), is introduced, aimed at enhancing stability. Mg, Zr, and B elements are strategically incorporated, with Mg and Zr primarily located inside particles and B predominantly on the surface, boosting both bulk and surface stability. NMZB exhibits outstanding electrochemical performance, with 90.5% capacity retention after 200 cycles at a 1C rate. This composition offers a pathway for cost-effective, high-performance lithium-ion battery technology. [Display omitted] Cobalt-free, high-nickel cathode materials are essential for the sustainable evolution of energy storage technologies, reducing the dependence on resources with significant environmental and social implications and simultaneously improving the efficiency and cost effectiveness of batteries. This paper introduces a cobalt-free, high-nickel cathode material called 0.01B-LiNi 0.98 Mg 0.01 Zr 0.01 O 2 (NMZB) developed using a novel blend of elements to enhance mechanical and surface chemical stability. Detailed evaluations confirmed the successful integration of Mg, Zr, and B into the particles, with Mg and Zr primarily located within the particle interior and B predominantly on the surface. This unique elemental configuration significantly improves the stability of the bulk phase and surface structure of the material. In addition, the refinement of primary particles within NMZB further enhances its mechanical stability. As a result, NMZB exhibits exceptional electrochemical stability, achieving 90.5 % capacity retention after 200 cycles at a 1C rate. This compositional strategy incorporates a high nickel content into layered materials while eliminating cobalt, which is crucial for advancing the development of cost effective and high-performance lithium-ion battery technology. [ABSTRACT FROM AUTHOR]

This work combines the nanoconfined material with the air-breathing gas diffusion electrode equips a wide practical range of applications for the synthesis of high-yield H 2 O 2 and upgrading of H 2 O 2 products. [Display omitted] • Yolk-shell SnS 2 @CSs Z-scheme nanoreactor is controllably synthesized. • Hydrogen peroxide production is increased through the nano-confinement effect. • Continuous hydrophobic layers allow air to spontaneously diffuse into the AGPE. • The photoelectrode has a good reusability and stability for activation of O 2 /H 2 O. • Hydrogen peroxide is produced under neutral condition media. The diffusion and adsorption properties of the O 2 /H 2 O corpuscles at active sites play a crucial role in the fast photo-electrocatalytic reaction of hydrogen peroxide (H 2 O 2) production. Herein, SnS 2 nanosheets with abundant interfacial boundaries and large specific areas are encapsulated into hollow mesoporous carbon spheres (CSs) with flexibility, producing a yolk-shell SnS 2 @CSs Z-scheme photocatalyst. The nanoconfined microenvironment of SnS 2 @CSs could enrich O 2 /H 2 O in catalyst cavities, which allows sufficient internal O 2 transfer, improving the surface chemistry of catalytic O 2 to O 2 − conversion and increasing reaction kinetics. By shaping the mixture of SnS 2 @CSs and polytetrafluoroethylene (PTFE) on carbon felt (CF) using the vacuum filtration method, the natural air-breathing gas diffusion photoelectrode (AGPE) was prepared, and it can achieve an accumulated concentration of H 2 O 2 about 12 mM after a 10 h stability test from pure water at natural pH without using electrolyte and sacrificial agents. The H 2 O 2 product is upgraded through one downstream route of conversion of H 2 O 2 to sodium perborate. The improved H 2 O 2 production performance could be ascribed to the combination of the confinement effect of SnS 2 @CSs and the rich triple phase interfaces with the continuous hydrophobic layer and hydrophilic layer to synergistically modulate the photoelectron catalytic microenvironment, which enhanced the transfer of O 2 mass and offered a stronger affinity to oxygen bubbles. The strategy of combining the confined material with the air-breathing gas diffusion electrode equips a wide practical range of applications for the synthesis of high-yield hydrogen peroxide. [ABSTRACT FROM AUTHOR]

[Display omitted] Dielectric effects and the coupled electrostatics between the nanoconfined and the internal/external aqueous media contribute to the observed deviations of chemistry within the nanoconfined environment when compared with unconfined systems. A systematic understanding has remained elusive, especially with respect to background salt concentration and boundary condition effects like the nanopore surface chemistry and the reference state used to calculate free energies. We utilize molecular dynamics simulations along with thermodynamic integration to determine the free energy difference associated with acid-base chemistry in 2 nm and 4 nm slit pores open to a bulk-like reservoir. pK a increases are predicted when confining acetic acid, formic acid, and bicarbonate in the slits at infinite dilution conditions. We find that confinement weakens the acids, and the modulation of outer pore surface dipole magnitudes can tune the pK a shift values, suggesting that purely "intrinsic" electrostatic effect on confinement may not exist. At sufficiently high salt concentrations, the dielectric/electrostatic effects on pK a values diminish due to charge screening effects. These discoveries enable future modifications of nanopore chemistries to achieve desirable properties for industrial applications. [ABSTRACT FROM AUTHOR]