Nanomaterials最新文献

Metal-organic frameworks (MOFs) have garnered significant attention in recent years for their potential to revolutionize heat exchanger performance, thanks to their high surface area, tunable porosity, and exceptional adsorption capabilities. This review focuses on the integration of MOFs into heat exchangers to enhance heat transfer efficiency, improve moisture management, and reduce energy consumption in Heating, Ventilation and Air Conditioning (HVAC) and related systems. Recent studies demonstrate that MOF-based coatings can outperform traditional materials like silica gel, achieving superior water adsorption and desorption rates, which is crucial for applications in air conditioning and dehumidification. Innovations in synthesis techniques, such as microwave-assisted and surface functionalization methods, have enabled more cost-effective and scalable production of MOFs, while also enhancing their thermal stability and mechanical strength. However, challenges related to the high costs of MOF synthesis, stability under industrial conditions, and large-scale integration remain significant barriers. Future developments in hybrid nanocomposites and collaborative efforts between academia and industry will be key to advancing the practical adoption of MOFs in heat exchanger technologies. This review aims to provide a comprehensive understanding of current advancements, challenges, and opportunities, with the goal of guiding future research toward more sustainable and efficient thermal management solutions.

Metal-oxide interfaces play a prominent role in heterogeneous catalysis. Tailoring the metal-oxide interfaces effectively enhance the catalytic activities and thermal stability of noble metal catalysts. In this work, polyvinyl alcohol-protected reduction and L-arginine induction methods are adopted to prepare Pd catalysts (Pd/Al₂O₃-xCeO₂) that are selectively decorated by CeO₂, which form core-shell-like structures and generate more Pd-CeO₂ interfacial sites, so that the three-way catalytic activity of Pd/Al₂O₃-xCeO₂ catalysts is obviously significantly enhanced due to more adsorption oxygen at the interface of Pd-CeO₂ and good low-temperature reducibility. At the moment, the Pd/Al₂O₃-xCeO₂ catalysts exhibit excellent thermal stability after being calcined at 900 °C for 5 h, owing to the Pd species being highly redispersed on CeO₂ and part of the Pd species being incorporated into the lattice of CeO₂. This is a major reason for the Pd/Al₂O₃-xCeO₂ catalysts to maintain high catalytic activity after aging at high temperatures. It is concluded that the metal-oxide interfaces and the interaction between Pd NPs and CeO₂ are responsible for the excellent catalytic performance and stability of Pd/Al₂O₃-xCeO₂ catalysts in three-way reactions.

Ti₃C₂T_x MXene, a novel two-dimensional transition metal carbide with nanoscale dimensions, has attracted significant attention due to its exceptional structural and performance characteristics. This review comprehensively examines various preparation methods for Ti₃C₂T_x MXene, including acid etching, acid-salt composite etching, alkali etching, and molten salt etching. It further discusses several strategies for interlayer exfoliation, highlighting the advantages and limitations of each method. The effects of these techniques on the nanostructure, surface functional groups, interlayer spacing, and overall performance of Ti₃C₂T_x MXene are evaluated. Additionally, this paper explores the diverse applications of Ti₃C₂T_x MXene in ceramic materials, particularly its role in enhancing mechanical properties, electrical and thermal conductivity, as well as oxidation and corrosion resistance. The primary objective of the review is to provide scientific insights and theoretical guidance for the preparation of Ti₃C₂T_x MXene and its further research and innovative applications in ceramic materials, advancing the development of high-performance, multifunctional ceramics.

Functionalized optical microcavities constitute an emerging highly sensitive and highly selective sensing technology. By combining optical microcavities with novel materials, microcavity sensors offer exceptional precision, unlocking considerable potential for medical diagnostics, physical and chemical analyses, and environmental monitoring. The high capabilities of functionalized microcavities enable subwavelength light detection and manipulation, facilitating the precise detection of analytes. Furthermore, recent advancements in miniaturization have paved the way for their integration into portable platforms. For leveraging the potential of microcavity sensors, it is crucial to address challenges related to the need for increasing cost-effectiveness, enhancing selectivity and sensitivity, enabling real-time measurements, and improving fabrication techniques. New strategies include the use of advanced materials, the optimization of signal processing, hybrid design approaches, and the employment of artificial intelligence. This review outlines the key strategies toward enhancing the performance of optical microcavities, highlights their broad applicability across various fields, and discusses the challenges that should be overcome to unlock their full potential.

In the face of escalating climate change due to excessive fossil fuel consumption, the urgency of addressing global warming has never been more critical [...].

In this computational study, we investigate two-sided functionalised MoS₂ with alkali metal atoms as donors and the organic acceptor molecule F₄TCNQ as an acceptor. Characterisation of functionalised MoS₂ involves first-principles calculations within the density functional theory (DFT) framework with a PBE+D3 scheme to investigate the electronic structure and quantify the charge transfer in the two-sided functionalised system in comparison to the one-sided functionalised counterpart. Within the two-sided functionalised systems, there is an increase in the overall charge on MoS₂ as a result of stronger electron transfer from the donor to the monolayer, additionally controlled by the ability of the acceptor to receive electrons.

Accurate flow stress prediction is vital for optimizing the manufacturing of lightweight materials under high-temperature conditions. In this study, a boron nitride (BN)-reinforced AZ80 magnesium composite was subjected to hot compression tests at temperatures of 300-400 °C and strain rates ranging from 0.01 to 10 s^-1. A data-driven Support Vector Regression (SVR) model was developed to predict flow stress based on temperature, strain rate, and strain. Trained on experimental data, the SVR model demonstrated high predictive accuracy, as evidenced by a low mean squared error (MSE), a coefficient of determination (R²) close to unity, and a minimal average absolute relative error (AARE). Sensitivity analysis revealed that strain rate and temperature exerted the greatest influence on flow stress. By integrating machine learning with experimental observations, this framework enables efficient optimization of thermal deformation, supporting data-driven decision-making in forming processes. The results underscore the potential of combining advanced computational models with real-time experimental data to enhance manufacturing efficiency and improve process control in next-generation lightweight alloys.

Aqueous zinc batteries, mainly including Zn-ion batteries (ZIBs) and Zn-air batteries (ZABs), are promising energy storage systems, but challenges exist at their current stage. For instance, the zinc anode in aqueous electrolyte is impacted by anodic dendrites, hydrogen and oxygen precipitation, and some other harmful side reactions, which severely affect the battery's lifespan. As for traditional cathode materials in ZIBs, low electrical conductivity, slow Zn²⁺ ion migration, and easy collapse of the crystal structure during ion embedding and migration bring challenges. Also, the slower critical oxygen reduction reaction (ORR), for example, in ZABs shows unsatisfactory results. All these issues greatly hindered the development of zinc batteries. Aerogel materials, characterized by their high specific surface area, unique open-pore structure formed by nanoporous structures, and excellent physicochemical properties, have a positive role in cathode modification, electrode protection, and catalytic reactions in zinc batteries. This manuscript provides a systematic review of aerogel materials, highlighting advancements in their preparation and application for zinc batteries, aiming to promote the future progress and development of aerogel nanomaterials and zinc batteries.

Current investigations into the fabrication of innovative biomaterials that stimulate cartilage development result from increasing interest due to emerging bone defects. In particular, the investigation of biomaterials for musculoskeletal therapies extensively depends on the development of various hydroxyapatite (HA)/sodium alginate (SA) composites. Cuttlefish bone (CFB)-derived composite scaffolds for hard tissue regeneration have been effectively illustrated in this investigation using a hydrothermal technique. In this, the HA was prepared from the CFB source without altering its biological properties. The as-developed HA nanocomposites were investigated through XRD, FTIR, SEM, and EDX analyses to confirm their structural, functional, and morphological orientation. The higher the interfacial density of the HA/SA nanocomposites, the more the hardness of the scaffold increased with the higher applied load. Furthermore, the HA/SA nanocomposite revealed a remarkable antibacterial activity against the bacterial strains such as E. coli and S. aureus through the inhibition zones measured as 18 mm and 20 mm, respectively. The results demonstrated a minor decrease in cell viability compared with the untreated culture, with an observed percentage of cell viability at 97.2% for the HA/SA nanocomposites. Hence, the proposed HA/SA scaffold would be an excellent alternative for tissue engineering applications.

Vortex dichroism in chiral metamaterials is of great significance to the study of photoelectric detection, optical communication, and the interaction between light and matter. Here we propose a compact chiral metamaterials structure composed of two elliptical SiO₂ rods covered with a Au film on a substrate to achieve a significant vortex-dichroism effect. Such a structure has different responses to a Laguerre-Gaussian beam carrying opposite-orbital angular momentum, resulting in giant vortex dichroism. The influences of various structural parameters are analyzed, and the optimal parameters are obtained to realize a remarkable vortex dichroism of about 58.5%. The simplicity and giant VD effect of the proposed metamaterials make it a promising candidate for advancing chiral optical applications such as optical communication and sensing.