ACS Applied Materials & Interfaces最新文献

A promising method for directing cell behavior and tissue regeneration is the use of smart materials that can transform physical inputs into bioelectrical signals. In this study, the mechanoelectrical control of preosteoblast activity was investigated using a piezoelectric smart biointerface based on positively poled poly(vinylidene fluoride) (PVDF). Distinct mechanical regimes, including vibrational and cyclic stretching, were applied through customized bioreactors, enabling controlled mechanoelectrical inputs ranging from 63 to 227 μVpp mm^-2. The biological response of MC3T3-E1 cells was evaluated in terms of metabolic activity, intracellular calcium signaling, alkaline phosphatase (ALP) activity, matrix mineralization, and gene expression (RUNX2, ALP, OPN, and OCN). The results demonstrated that stretching stimulation combined with higher mechano electric inputs (113-227 μVpp mm^-2) enhanced calcium influx and enhanced osteogenic differentiation, while lower impulses (∼63 μVpp mm^-2) under vibrational circumstances increased cell proliferation. These findings highlight the intensity- and mode-dependent nature of mechanoelectrical signaling in regulating osteogenic commitment. All things considered, this study shows how piezoelectric smart materials can be used as bioresponsive platforms to precisely control cell proliferation and differentiation, creating avenues for bone tissue engineering's next-generation regenerative techniques.

The pursuit of durable and eco-friendly antifouling surfaces has become a critical challenge across engineered systems, ranging from architectural coatings to marine infrastructure. Herein, we propose an innovative stepwise physicochemical antifouling mechanism through the rational integration of hierarchical superamphiphobic architectures with bactericidal copper oxide nanoparticles. The designed coating operates via a sequential defense protocol: physical antiadhesion enabled by a superamphiphobic surface exhibiting ultralow surface energy, coupled with a chemical antibacterial effect through controlled Cu²⁺ ion release from embedded CuO nanoparticles. When the action time reaches 24 h, the coating shows excellent antibacterial effects against Gram-negative Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), and Gram-positive Staphylococcus aureus (S. aureus). A scalable spray-coating technique was developed using 3-aminopropyltriethoxysilane (APTES)-functionalized CuO/SiO₂ nanocomposites with 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) modification for the coating fabrication. Systematic characterization combining Cassie-Baxter modeling, X-ray Photoelectron Spectroscopy (XPS) analysis, and bacterial viability assays confirms the mechanistic coupling between topographical liquid repellency and chemical bactericidal activity. The contact angle (CA) value of CuO-SiO₂/APTES@PFDTES calculated by dynamic density functional theory (DDFT) is 165.5°. This work provides a promising strategy for the rational design of advanced superamphiphobic antifouling coatings through physicochemical antibacterial strategies.

Rational design of efficient and robust electrocatalysts for the oxygen evolution reaction (OER) is essential for advancing electrochemical water splitting systems. In this work, we report an Fe-incorporated NiCo layered double hydroxide (NiCoFe-LDH) nanosheet array grown directly on three-dimensional (3D) nickel foam via a facile hydrothermal route. Among the various compositions investigated, optimized NiCoFe-LDH exhibits significantly enhanced OER activity, delivering a low overpotential of 215 mV at 100 mA cm^-2 and maintaining long-term catalytic stability. Structural and compositional analyses reveal that Fe incorporation induces a distinct electronic modulation: Fe doping downshifts the d-band center, which weakens the adsorption of key OER intermediates such as *O and lowers the reaction energy barrier for the rate-determining step, thereby accelerating OER kinetics. Bader charge analysis and the crystal orbital Hamilton population further support weakened metal-oxygen bonding upon Fe substitution. The combined modulation of the local electronic structure and active site configuration provides clear mechanistic insight into the origin of the enhanced OER activity, presenting an effective design strategy for developing transition metal-based electrocatalysts with high OER performance.

Radiative cooling is a passive cooling technology that could potentially address critical sustainability challenges by improving energy efficiency across different applications, including building materials, coatings, electronics, and outdoor devices. Photonic radiative coolers are a discrete category that utilizes photonic structures to optimize the emission properties of the material in the atmospheric transparency window (ATW) regime (8-13 μm). Due to their efficiency and adaptive nature, photonic radiative coolers offer a promising avenue as an adaptable cooling technology. However, a major challenge in transitioning this technology from laboratory to practical use remains. To address this barrier, large area, scalable and low-cost methods and materials need to be implemented. In this study, we demonstrate the fabrication of a transparent microstructured polymer-based radiative cooling (MPRC) film using nanoimprint lithography with a hybrid organic-inorganic UV-curable resist, namely, Ormocomp. We report the optical properties of Ormocomp within the atmospheric transparency window, which had not been previously characterized and utilize them to reveal the underlying mechanisms leading to emissivity enhancement. The MPRC film has over 90% transmission in the visible-NIR wavelengths and provides an─above ambient─cooling effect of -3 °C compared to bare Si reference sample under direct sunlight even though the solar absorptivity of silicon is lower. Our suggested design and fabrication approach is suitable for applications that need optical transparency or can be paired with reflective substrates to further enhance cooling performance, offering a practical and scalable radiative cooling solution.

Facing escalating water scarcity, solar-driven interfacial evaporation (SDIE) has emerged as a sustainable desalination paradigm. However, practical deployment is hindered by the trade-off between thermal localization, water transport, and salt resistance in conventional materials. Herein, we report a hollow-porous carbon nanofiber membrane loaded with CuS nanoparticles (CuS@HPCNFs) fabricated via coaxial electrospinning. The through-porous architecture reduces thermal conductivity, while the plasmonic CuS nanoparticles enable broadband absorption, achieving a surface temperature of 92.8 °C under 1 sun illumination. Consequently, CuS@HPCNFs delivers an evaporation rate of 2.39 kg·m^-2·h^-1 with a solar-to-vapor efficiency of 83.5%, calculated via energy balance accounting for conduction, convection, and radiation losses. The hydrated CuS surface disrupts the hydrogen-bond network of interfacial water, reducing the evaporation enthalpy to 1816 J·g^-1. The material exhibits stable performance in 15 wt % NaCl brine for 10 h and significantly reduces metal ion concentrations in seawater under outdoor conditions. This work provides a structural-functional coupling paradigm for developing scalable SDIE materials.

Irradiation induced structural changes of actinide oxide materials is a key consideration in their development and use as nuclear fuels. This study reported on the synthesis of ThO₂ and Th_1-xU_xO₂ (x = 0.15, 0.50) thin films, fabricated using electrospray-assisted solution combustion synthesis, and their responses to ion irradiation. Krypton ion irradiations, up to a fluence of 1 × 10¹⁶ ions/cm², were carried out to simulate radiation damage induced by fission products in a reactor environment. Structural and chemical changes induced by irradiation were analyzed using high-resolution scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDS), and electron energy-loss spectroscopy (EELS). It was determined that the extent and nature of irradiation-induced damage are strongly correlated with the uranium content. ThO₂ films were most susceptible to radiation-induced damage, with significant cavity formation and delamination from the substrate at high fluence. Of the compositions studied, Th_0.85U_0.15O₂ films showed the highest stability, characterized by moderate grain growth and the absence of voids or severe defect structures. In contrast, Th_0.5U_0.5O₂ films accumulated extensive damage, including the formation of a nanocrystalline central region. EELS analysis indicated that oxygen displacement is the primary driver of structural degradation in Th_0.5U_0.5O₂ films. α-particle spectroscopy confirmed minimal actinide loss across all compositions, underscoring the mechanical robustness of the films. These findings provide insight into the irradiation-induced damage mechanisms in ThO₂ and Th_1-xU_xO₂ systems, supporting their development as potential materials for nuclear fuels and irradiation-tolerant thin film targets in nuclear physics measurements.