Advanced Materials Interfaces最新文献

Biphilic Functional Surfaces

This artwork, inspired by surrealism, highlights the functionality of biphilic surfaces to be used in energy systems and features a wind turbine integrated with a clock, symbolizing the passage of time. Biphilic surfaces of turbine blades delay frost formation while also facilitating defrosting. More details can be found in article 2400412 by Ali Koşar and co-workers.

Chemically modified graphene is an attractive electrode material for electrocatalysis, energy devices, and sensors, whereas pristine graphene is electrochemically passive. The remarkable anisotropic electrochemical nature of graphene is uncovered by π–π interaction, making pristine graphene more active than bare Au. The π–π stacking during redox reaction “dopes” the graphene, disrupting the passivating hydration layer, making it a facile electrochemical electrode. The structure during π–π stacking-mediated redox of methylene blue (MB) is quantitatively measured by the differential reflectivity of a polarized laser on a ≈100 micron spot. The local redox reaction current varies over fourfold due to the orientation of the ≈10 micron size grains. The mosaic-grain anisotropy on each spot shows local uniaxial orientation. The redox signal at the optimum orientation is over 2.5-fold greater than that for bare Au on the same electrode. The redox signal is over fivefold greater at the edges of graphene compared bare Au. Remarkably, the π–π interaction increases chemical stability significantly, leading to negligible photo-degradation at the approximate absorption wavelength of MB. The exclusive redox activity due to π–π interaction on pristine graphene adds to the toolbox of making exotic opto-electrochemical electrode materials for electrocatalysis, sensing, and electronics.

This work focuses on combating bacterial infections in bone tissue using metal elements embedded in bioactive glass. While there is an urgent need for alternative methods with a shrinking number of effective treatment options untouched by antimicrobial resistance, it is crucial to first understand the mechanisms of pathogenesis, persistence, and bacterial resistance in skeletal infection, and then develop effective counterstrategies and innovative alternatives. This review considers the role of antimicrobial metal ions, their mechanism of action, and their incorporation into bioactive glass formulations as these materials can serve as delivery platforms with the least possible complexities. Furthermore, the bacterial infection risk in bone is also examined with specific attention to antibiotic resistance and biofilm formation. This review sheds light on the most promising materials as novel antibacterial agents by presenting a wide range of possible bioactive glass formulations equipped with potential antibacterial ions and in vitro/ in vivo insights, and it also reinforces the importance of continuing studies to develop multi-faceted antibacterial bioactive glasses.

This work presents a study of piezoelectric zinc oxide (ZnO) thin films deposited by a novel post-reactive sputtering method. The process utilizes a rotating drum with DC magnetron sputtering deposition onto substrates with subsequent DC plasma-assisted oxidation of the deposited metal to metal oxide. The paper analyzes the influence of plasmaassisted magnetron sputtering (PA-MS) deposition parameters (O₂ plasma source power, O₂ flow, and Ar flow) on the morphological, structural, optical, and piezoelectric properties of ZnO thin films. Design of experiments has been utilized to evaluate the role of these parameters on the growth rate (r_g) and the properties of resulting films. Results indicate a predominant influence of the plasma power on the r_g over other parameters. Among the eight tested samples, three of them show high crystal quality with high intensity (0001) diffraction peak, characteristic of the wurtzite crystalline structure of ZnO, and one of them exhibits piezoelectric coefficient values of ≈11pC N⁻¹. That sample corresponding to a ZnO film deposited at the lowest r_g of 0.075 nm s⁻¹, confirmed the key role of the deposition parameters on the piezoelectric response of films, and demonstrated PA-MS as a promising technique to produce high-quality piezoelectric thin films.

The present work addresses the systematic accurate fabrication and design of biphilic surfaces having superhydrophobic circular islands surrounded by a hydrophilic background by investigating their condensation frosting and defrosting behavior. A significant delay in frost formation is observed on samples with higher superhydrophobicity ratio A^*, defined as superhydrophobic area to total area ratio. As the superhydrophobic island diameter D increases from D = 500 µm to D = 700 µm (A^* from 19.62% to 38.46%), a 50% improvement/delay is observed in terms of frost formation or densification. Besides delaying icing/frosting, the presence of superhydrophobic areas empowers the formation of porous and nonuniform frost structure, which facilitates ice removal during the defrosting process. To this end, as the surface is recovered the ambient temperature, almost complete passive cleaning performance within only 23 s is observed on the biphilic design having superhydrophobic islands with the diameter of D = 500 µm, that is, a superhydrophobicity ratio A^* of 19.62%. This work concludes on the optimum biphilic ratio, which is not only effective as a passive method by hindering frosting but also leads to a slush/water free surface after defrosting eased by the Laplace pressure gradient which is imposed by the different biphilic wettability patterns.

A systematic series of industrial-relevant polystyrene-based anion exchange resins that are functionalized with hydro- or fluorocarbon chains are compared regarding their adsorption behavior toward perfluorocarboxylic acids (PFCA) in respect to their charge, chain length, and type of chain. The results clearly show the dominance of electrostatic interactions in the adsorption process as uncharged adsorber materials showed no adsorption at all. In contrast, the charged adsorber materials showed in general a PFCA removal of 80% to 30% over the experiment depending on effluent fraction. Unexpectedly, for perfluorobutanoic acid (PFBA) the highest removal rate is found with consistently >90%. Despite observing significant benefits in the adsorption of PFCA for fluoroalkylated adsorbers in comparison to their non-fluorinated counterparts, this effect of fluoroalkylation is comparatively small and can not be clearly attributed to fluorophilic interactions between the fluoroalkyl chains. These findings help clarifying that the introduction of fluorocarbon moieties in adsorber materials is not necessary in order to remove fluorocarbon molecules from the environment.

Controlling the morphology of 2D transition metal dichalcogenides (TMDs) plays a key role in their applications. Although chemical vapor deposition can achieve wafer-scale growth of 2D TMDs, a comprehensive theoretical framework for effective growth optimization is lacking. Atomistic modeling methods offer a promising approach to delve into the intricate dynamics underlying the growth. In this study, kinetic Monte Carlo (kMC) simulations are employed to identify crucial parameters that govern the morphology of MoS₂ flakes grown on diverse substrates. The simulations reveal that large adsorption rates significantly enhance growth speed, which however necessitates rapid edge migration to achieve compact triangles. Substrate etching can tune the adsorption–desorption process of adatoms and enable preferential growth within a specific substrate region, controlling the flake morphology. This study unravels the complex dynamics governing 2D TMD morphology, offering a theoretical framework for decision-making in the design and optimization of TMD synthesis processes.

Redox Splitting of CO₂

Solar fuels are produced from CO₂ and H₂O via a thermochemical redox cycle using concentrated solar radiation. In article 2300452, Steinfeld, Studart, and co-workers produced solar fuels from CO₂ and H₂O via a thermochemical redox cycle using concentrated solar radiation. The solar reactor contains a structure, made of ceria, which serves the functions of solar absorber and redox material. Hierarchically channeled ceria structures, 3D-printed by direct ink writing, enable efficient volumetric radiative absorption, thereby augmenting the specific fuel yield of the solar reactor.