Materials Horizons最新文献

A synchronous way of energy generation and storage in a single portable device is in high demand for the development of high-end electromagnetic interference (EMI) free modern electronics. Thus, this study highlights the devising of a piezoelectrically self-chargeable symmetric supercapacitor (PSCS) device using a polyvinyl alcohol (PVA)/succulent inspired grown g-C₃N₄@lithium sodium niobate (GNLNN)/potassium hydroxide (KOH) based piezo separator with GNLNN electrode. The GNLNN electrode exhibits a surface capacitive controlled specific capacitance of 503 F g^-1. The PSCS device exhibits an energy density of 15.3 W h kg^-1 and a power density of 4.2 kW kg^-1 with an impressive capacitive retention capability of 93.2% after 6000 cycles of charging-discharging. The PSCS device can be charged up to 393 mV within 180 s under 14.2 N of cyclic pressing by human finger imparting. The fabricated PSCS device was also investigated for self-charging potential regulated smart EMI shielding applications. The smart PSCS device achieves an 88.3 dB increment from 40.9 dB of EMI shielding under charging from 0 mV to 300 mV. The increased charging potential of the PSCS device enhances the destructive interference and leads to boosted absorption and decreased reflection of incident EM radiation.

Owing to the extensive use of antibiotics for treating infectious diseases in livestock and humans, the resulting residual antibiotics are a burden to the ecosystem and human health. Hence, for human health and ecological safety, it is critical to determine the residual antibiotics with accuracy and convenience. Graphene-based electrochemical sensors are an effective tool to detect residual antibiotics owing to their advantages, such as, high sensitivity, simplicity, and time efficiency. In this work, we comprehensively summarize the recent advances in graphene-based electrochemical sensors used for detecting antibiotics, including modifiers for electrode fabrication, theoretical elaboration of electrochemical sensing mechanisms, and practical applications of portable electrochemical platforms for the on-site monitoring of antibiotics. It is anticipated that the current review will be a valuable reference for comprehensively comprehending graphene-based electrochemical sensors and further promoting their applications in the fields of healthcare, environmental protection, and food safety.

Surface protection is essential when using wood as a construction material. However, the industry lacks sustainable alternatives to replace the presently dominant fossil-based synthetic water-resistant coatings. Here, we show a fully bio-based wood surface protection system using components sourced from birch bark and spruce bark, inspired by the natural barrier function of bark in trees. The coating formulation contains suberinic acids and spruce bark polyphenols, resulting in a waterborne suspension that is safe and easy to apply to wood. The polyphenols play a dual role in the formulation as they stabilize the water-insoluble suberinic acids and serve as nanofillers in the thermally cured coating, enabling the adjustment of the mechanical properties of the resulting coating. When applied to spruce wood, the coating formulation with 10% polyphenol and 90% suberinic acids achieved a water absorption value of 100 g m^-2 after 72 hours of water exposure, demonstrating superior performance compared to an alkyd emulsion coating. We conclude that instead of combusting tree bark, it can serve as a valuable resource for wood protection, closing the circle in the wood processing industry.

Both the circular economy and fire-safety of polymer plastics have become a global consensus. Herein, an integrated strategy for selectively self-recyclable, highly-transparent and fire-safe polycarbonate plastic is proposed by thermally responsive phosphonium-phosphate (DP). During its service life, DP, as a flame-retardant with good compatibility, enables polycarbonate plastic with high transparency in visible light, excellent self-extinguishing and high fire-safety. After consumption, DP, as a catalyst, triggers the selective self-recycling of DP-containing polycarbonate in mixed plastics and even in same-kind polycarbonate plastics without an external catalyst. Importantly, the oxygen-consuming mechanism at high temperature in fire accidents (>350 °C) and the double hydrogen bond catalysis mechanism at a lower temperature (180 °C) of DP are key to the life cycle management of polycarbonate from use-stage to post-consumption. This work inspires a new solution to plastic pollution by designing sustainable plastics that satisfy both service-stage and end-of-life criteria, striving towards a zero-waste circular economy.

Gas sensors convert gas-related information into usable data by monitoring changes in conductivity and chemical reactions resulting from the adsorption of gas molecules. Recently, perovskites have emerged as promising candidate materials for gas sensors, owing to their polar reactivity, chemical responsiveness, and sensitivity. These characteristics enable the detection of the presence and concentration of various gases. This article provides a concise review of recent advancements in perovskite-based gas sensors. First, the chemical composition, structure, and preparation methods of perovskites, as well as the effects of their structure on gas sensing performance, are examined. The key performance parameters of the sensor and the sensing mechanism of the perovskite-based gas sensor are discussed. Then the development of gas sensors based on different structural types of perovskites, including single-component perovskites, mixed-component perovskites, and metal-oxide perovskites, is discussed. Finally, the challenges and opportunities for gas sensors based on perovskites are summarized and prospected.

Communication in biological systems typically involves enzymatic reactions that occur within fluids confined between the soft, elastic walls of bio-channels and chambers. Through the inherent transformation of chemical to mechanical energy, the fluids can be driven to flow within the confined domains. Through fluid-structure interactions, the confining walls in turn are deformed by and affect this fluid flow. Imbuing synthetic materials with analogous feedback among chemo-mechanical, hydrodynamic and fluid-structure interactions could enable materials to perform self-driven communication and self-regulation. Herein, we develop computational models to determine how chemo-hydro-mechanical feedback affects interactions in biomimetic arrays of chemically active and passive micro-posts anchored in fluid-filled chambers. Once activated, the enzymatic reactions trigger the latter feedback, which generates a surprising variety of long-range, cooperative motion, including self-oscillations and non-reciprocal interactions, which are vital for propagating coherent, directional signals over net distances in fluids. In particular, the array propagates a distinct message; each post interprets the message; and the system responds with a specific mode of organized, collective behavior. This level of autonomous remote control is relatively rare in synthetic systems, particularly as this system operates without external electronics or power sources and only requires the addition of chemical reactants to function.

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a popular conduction polymer and widely used in organic electronics, bioelectronics and printed electronics. It is believed that PEDOT:PSS has a core-shell colloidal structure dispersed in the formulation. However, the size and surface functional groups of the PEDOT:PSS dispersion and films remain to be visualized. Here, we have introduced the concept of aggregation-induced emission (AIE) to super-resolution imaging for designing the cationic probe TPE-4N+ and accomplished the nanoscale optical visualization of PEDOT:PSS films through reversible electrostatic interactions. Information on the PEDOT:PSS size and surface charge has been successfully collected via super-resolution imaging. The full-width at half-maximum (FWHM) of PSS nanoparticles was observed to be approximately 30-40 nm. The super-resolution fluorescence imaging method can also be used to monitor the PEDOT:PSS film after acid treatment. It was observed that PSS chains were washed away when exposed to concentrated sulfuric acid, which explains why concentrated sulfuric acid treatment greatly improves the conductivity of the PEDOT:PSS film. Super-resolution imaging is promising as an effective method for characterizing PEDOT:PSS films.

Correction for ‘An amorphous Cr₂Ge₂Te₆/polyimide double-layer foil with an extraordinarily outstanding strain sensing ability’ by Yinli Wang et al., Mater. Horiz., 2024, https://doi.org/10.1039/d4mh00616j.

van der Waals ferroelectric CuInP₂S₆ (CIPS) has drawn significant attention not only because of its unique properties but also owing to its technological potential for nanoelectronics. Mechanical polarization switching provides a new approach to modulating polarization states through flexoelectricity. This approach is particularly favourable for CIPS to avoid surface damage under an electric field due to the coupling between polarization switching and ionic motion. Here, we report anomalous downward-to-upward polarization switching under tip force in CIPS nanoflakes, which is believed to stem from the competition between piezoelectric and flexoelectric fields induced by tip pressure, together with the unique quadruple-well state present in CIPS. This work provides novel insights into the polarization switching mechanism of CIPS, elucidating the interplay between competing piezoelectric and flexoelectric fields, and it may pave the way for the design of electromechanical devices based on flexoelectric engineering.

Carbamazepine, recognized as one of the most prevalent pharmaceuticals, has attracted considerable attention due to its potential impact on ecosystems and human health. In response, this work synthesized and characterized a novel environmentally friendly and cost-effective organic semiconductor photocatalyst PM6:Y6:ITCPTC loaded with coconut shell charcoal, and then investigated its performance for photocatalytic removal. Remarkably, carbamazepine demonstrated a photodegradation efficiency exceeding 99% within a mere 20 minutes of exposure to one sunlight intensity, and also showed good effectiveness under a low light intensity of 50 W. The catalyst exhibited exceptional reusability and stability, maintaining degradation efficiency between 95-99% over 25 cycles. The high photocatalytic activity of PM6:Y6:ITCPTC is primarily attributed to the incorporation of the third component (named ITCPTC), which enhances exciton dissociation and carrier transfer, generating superoxide radicals, electrons, and holes. Furthermore, the plausible degradation pathway of carbamazepine was proposed based on the measured intermediates and density functional theory calculations.