RSC Applied Interfaces最新文献

The structural isomeric effect on the conjugation-break spacers (CBSs) design in stretchable conjugated polymers hasn't been investigated. In addition, achieving isotropic mobility–stretchability performance is challenging, as crack formation and polymer chain alignment can make the mobility anisotropic. In this study, three alicyclic CBSs were incorporated into the backbone of naphthalenediimide (NDI)-based n-type semiconducting polymers to enhance their mechanical and electronic performance. Of the three CBSs, 2,5-tricyclodecanedimethanol (TCD–CBS) and an isomeric mixture of tricyclodecanedimethanol (rTCDs–CBS) feature tricyclic structures derived from dicyclopentadiene, whereas trans-1,4-cyclohexanediol (tCH–CBS) incorporates a monocyclic structure. The experimental results demonstrate that the structural configuration of the CBS units has a significant influence on polymer aggregation, crystallinity, chain alignment, and mechanical stability. TCD, with its rigid tricyclic structure of TCD–CBS that promotes predominant face-on stacking, delivers high initial mobility but lacks mechanical durability under strain. In contrast, tCH features a flexible monocyclic structure of tCH–CBS that favors edge-on stacking, enables isotropic transport, but suffers from low mobility and poor structural stability due to its high chain conformability under deformation. However, unlike TCD and tCH, rTCDs comprising rTCDs–CBS offers balanced performance by introducing moderate structural disorder that supports a bimodal molecular orientation. This configuration increases free volume and creates additional charge carrier pathways, allowing the polymer to maintain ductility and stable charge transport under strain. After 1000 cycles at 40% strain, rTCDs retained 77% of their mobility in the parallel direction and 104% in the perpendicular direction, relative to single-cycle performance. These results highlight the potential of isomeric design in CBS units to achieve both mechanical flexibility and isotropic electronic performance in stretchable semiconducting polymers for wearable and deformable electronics.

Indium sulfide thin films play a crucial role in photoelectrochemical (PEC) water splitting, offering promising strategies to mitigate energy shortages and global warming. In this study, indium sulfide thin films were synthesized via a hydrothermal method, and the effects of sulfur precursors—L-cysteine (LC) and L-cysteine hydrochloride (LCHCl)—along with hydrothermal temperature ramp rates (3 and 10 °C min⁻¹) on their crystallographic orientation, morphology, and thickness were investigated. The findings revealed that films synthesized with LC predominantly exhibited the (440) facet, while those synthesized with LCHCl had the (311) facet. Additionally, films produced at 3 °C min⁻¹ were thicker than those synthesized at 10 °C min⁻¹. The film (LC-IS-10) synthesized at 10 °C min⁻¹ using LC achieved a photocurrent density of 3.7 mA cm⁻² at −0.2 V vs. Ag/AgCl, which outperformed that of LCHCl-synthesized film (LCHCl-IS-10) at the same heating rate (2.6 mA cm⁻²) and those of the films synthesized at 3 °C min⁻¹ (LC-IS-3: 0.7 mA cm⁻² and LCHCl-IS-3: 2 mA cm⁻²). 2-Hour photocurrent stability assessments indicated that LC-synthesized films (LC-IS-3: 1 mA cm⁻², LC-IS-10: 670 μA cm⁻²) exhibited superior stability to the LCHCl-synthesized films (LCHCl-IS-10: 90 μA cm⁻², LCHCl-IS-3: 33 μA cm⁻²). This improved stability was attributed to their (440) facet, which was structurally more compact and symmetric and exhibited reduced sulfur exposure than the less ordered (311) facet. Although the LC-IS-3 film had the lowest photocurrent density, it showed enhanced stability, owing to the thickness alteration caused by the oxidation of surface S²⁻ species. This research provides insights for optimizing material design in PEC water-splitting applications, advancing sustainable energy solutions.

Molecularly imprinted polymers (MIPs) and electrochemical sensors offer a promising route for rapid and onsite detection of per- and polyfluoroalkyl substances (PFAS). The quantity and quality of the imprinted cavities in MIPs underpin the selective recognition and sensing performance of MIP-based sensors. Thus, understanding the role of various synthesis parameters during the electropolymerization of MIPs is crucial to control the imprinting process for various PFAS templates. Herein, we demonstrate that the synthesis scan rate used during electrosynthesis of MIPs can be leveraged to modulate the imprinting efficiency of PFAS with different tail lengths within a poly(ortho-phenylenediamine) (PoPD) film. Specifically, we test the hypothesis that increasing the scan rate, which reduces the thickness of the diffusion boundary layer during electropolymerization, significantly increases the density of imprinted PFAS in the resulting MIP-based sensors. We characterize the total amount and the spatial distribution of the imprinted cavities via cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS) sputter depth profiling (SDP), respectively. We demonstrate that both properties depend on the nature of the diffusion boundary layer and the identity of the PFAS templating molecules (i.e., perfluorooctane sulfonic acid, PFOS; perfluorohexane sulfonic acid, PFHxS; perfluorobutane sulfonic acid, PFBS). We further show that the cyclic voltammogram during the electrosynthesis can be modeled using finite element analysis to describe the effect of different synthesis scan rates. We anticipate that our results will provide further insights into the development and optimization of PoPD MIP-based sensors for perfluoroalkyl sulfonic acids (PFSA) towards the applications of decentralized sensors.

This study addresses rapid charge recombination and instability in MAPbI₃ photocatalysts for hydrogen production by constructing a Nb₂CT_x MXenes-modulated composite. Leveraging Nb₂CT_x metallic conductivity for efficient electron extraction and proton reduction sites, the composite enables robust photocatalytic HI splitting in strong acid. In situ coupling achieved intimate heterointerface contact with Z-scheme characteristics, yielding a remarkable hydrogen evolution rate of 12 046.77 μmol h⁻¹ g⁻¹—a 344-fold enhancement over pristine MAPbI₃—while retaining ∼85% activity after 5 cycles. UPS and theoretical calculations confirm a strong built-in electric field at the heterointerface accelerates carrier separation. Critically, the Z-scheme simultaneously suppresses recombination and preserves strong redox capabilities. This interface engineering synergistically enhances efficiency and stability, resolving the charge separation-redox capability trade-off in conventional type II heterojunctions.

With the growing demand for thinner and more flexible electrochromic devices (ECDs), proper electrolyte selection is critical for the design and implementation of these systems. Compared to a traditional liquid electrolyte, polymer gel electrolytes have received growing application in ECDs due to their efficient ion transport, high stability, and, most importantly, zero risk of leakage during device integration. In this work, we capitalize on these features in the design, fabrication, and testing of a flexible and multifunctional polymer gel electrolyte using a polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) matrix enriched with ionic liquids and plasticizers that interface with adjacent electrochromic pixels. This polymer gel electrolyte remains stable at room temperature, enabling operation of ECD pixel elements over 2750 cycles and 2.5 days of continuous operation. Applications such as passive color filtering using the electrolyte are also explored, highlighting its potential to improve operation and expand colour range without modification of the electrochromic film.

Here, we report the hydrothermal synthesis of Mn₃O₄ nanomaterial and Mn₃O₄/rGO nanocomposite (rGO, reduced graphene oxide). The prepared nanocomposite (NC) was electrophoretically deposited (EPD) on indium tin oxide (ITO) to fabricate the Mn₃O₄/rGO/ITO electrode, which is further utilized for the electrochemical estimation of 2,4,6-trichlorophenol (2,4,6-TCP). The charge transfer rate constant, diffusion coefficient (D), and surface concentration values evaluated for the Mn₃O₄/rGO/ITO electrode are 0.53 s⁻¹, 0.86 × 10⁻⁶ mol cm⁻², and 0.358 cm² s⁻¹, respectively. The electrochemical sensor displays a linear extent of 2,4,6-TCP detection from 1 to 500 μM with a limit of detection (LoD) of 0.038 μM and sensitivity of 2.17 Ω μM⁻¹ cm⁻². Here, we demonstrate the 2,4,6-TCP detection via electrochemical impedance spectroscopy (EIS) sensing and photocatalytic degradation, as well as the kinetics of methylene blue (MB) dye, analyzed in parallel with bare Mn₃O₄ under UV light irradiation. The results indicate that Mn₃O₄/rGO NCs have preferred MB photodegradation efficacy with a reaction rate constant and low degradation time compared to bare Mn₃O₄ nanomaterials (NMs). The rate constants for the Mn₃O₄ and Mn₃O₄/rGO NCs were found to be 0.00075 and 0.0197, respectively, and the MB dye degradation reached up to 6% with the Mn₃O₄ catalyst and up to 80% with the Mn₃O₄/rGO catalyst when exposed to UV light for 80 minutes.

Natural non-wettable surfaces, such as lotus leaves, exhibit exceptional self-cleaning properties due to their unique micro- and nanostructures. This has inspired researchers to develop artificial superhydrophobic materials, particularly on mica and SiO₂-based substrates, such as glass, using organosilanes to achieve tailored properties. This study focused on modifying glass surfaces with vinyltrichlorosilane (VTCS) and allyltrichlorosilane (ATCS) to create coatings with enhanced optical properties, wettability, and stability. We employed a two-step surface modification strategy: dip-coating followed by functionalization with 1-decanethiol through radical-initiated thiol–ene click reaction to functionalize these surfaces with a long alkyl chain to enhance hydrophobicity and improve chemical stability. The morphology, structure, and chemical composition of the coatings were characterized by using a combination of techniques, including scanning electron microscopy, atomic force microscopy, attenuated total reflectance-Fourier transform infrared spectroscopy, and photo-induced force microscopy (PiFM). PiFM was specifically employed to assess the uniformity of surface functionalization, both at the surface and throughout the film's depth, and to quantify the efficiency of the thiol–ene click reaction.

The chemical deposition of high-performance zinc oxide (ZnO) thin films is challenging, thus significant efforts have been devoted during the past decades to develop cost-effective, scalable fabrication methods in gas phase. This work demonstrates how ultra-short-pulse laser beam scanning (LBS) can be used to modulate electrical conductivity in ZnO thin films deposited on soda–lime glass by spatial atomic layer deposition (SALD), a high-throughput, low-temperature deposition technique suitable for large-area applications. By systematically optimizing laser parameters, including pulse energy and hatching distance, significant improvements in the electrical performance of 90 nm-thick ZnO films were achieved. The optimization of the laser annealing parameters – 0.21 μJ per pulse energy and a 1 μm hatching distance—yielded ZnO films with an electrical resistivity of (9 ± 2) × 10⁻² Ω cm, 3 orders of magnitude lower than as-deposited films. This result suggests that laser post-deposition processing can play an important role in tailoring the properties of ZnO thin films. Excessive laser intensity can compromise structural integrity of the films, however, degrading their electrical transport properties. Notably, the electrical resistance of laser-annealed ZnO films exhibited high sensitivity to oxygen concentration in the surrounding atmosphere, suggesting exciting prospects for application in devices based on transparent oxygen sensors. This study thus positions ultra-short pulsed laser annealing as a versatile post-deposition method for fine-tuning the properties of ZnO thin films, enabling their use in advanced optoelectronic and gas-sensing technologies, particularly on temperature-sensitive substrates.

Adsorbents such as activated carbon and ion exchange resins have several limitations, including high operational and regeneration costs. These drawbacks have prompted the search for alternative adsorbent materials that offer benefits such as cost-effectiveness, chemical stability, safe regenerability, and minimal waste generation. Alkali-activated materials (AAMs) have emerged as a promising solution, especially when engineered into larger forms—such as casted columns—via alkali-activation manufacturing. This approach not only broadens their applicability across various processes but also enhances surface area and porosity, thereby improving adsorption performance. In this study, titanate-modified metakaolin was cast into a column, achieving multimetal adsorption capacities of 13.4, 32.3, 43.3, 49.0, 52.8, 54.0, 61.8, and 66.6 mg g⁻¹ for Li, Ni, Co, Zn, Mn, Cu, Cd and Pb, respectively. The regeneration ability of AAM adsorbent was demonstrated through 31 consecutive adsorption–desorption cycles. A novel regeneration chemical, 0.5 M citric acid (pH 6.6), exhibited exceptional regeneration potential without compromising the mechanical strength of the AAM—an issue commonly encountered with other regeneration chemicals. The removal efficiency remained above 95% throughout all cycles, indicating only a 4% reduction in adsorption performance. Both adsorption and regeneration mechanisms were proposed in this study. The AAM was characterized using X-ray diffraction (XRD), X-ray spectroscopy (XPS), X-ray fluorescence (XRF), field emission scanning electron microscopy with energy-dispersive X-ray spectrometry (FESEM-EDS), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The sustainability and economic viewpoint of the process was studied through a life-cycle assessment (LCA) method.

Polyurethane (PU) coatings are widely utilized in fields such as construction, electronics, transportation, and aerospace due to their excellent mechanical properties, resistance to chemical corrosion, and tunable molecular structure. However, their inherent flammability significantly restricts their application in environments with high fire safety requirements. Moreover, single-functionality is no longer sufficient to meet the demands of complex application environments. In recent years, researchers have developed multifunctional flame-retardant PU coatings that combine flame retardancy with additional functionalities, such as corrosion resistance, self-healing, and hydrophobicity, through the application of nanocomposites, surface modification techniques, and synergistic flame-retardant systems. This paper systematically reviews the flame-retardant mechanisms and functional design strategies of advanced polyurethane coatings, with the aim of providing valuable references for the design and development of next-generation high-performance flame-retardant materials.