Advanced Composites and Hybrid Materials最新文献

Biopolymer composites are emerging as promising materials for smart sensors in the fields of civil engineering and intelligent cities. With enhanced mechanical properties, tailored sensitivity, and versatile fabrication methods, biopolymer composites provide a compelling solution for sustainable sensing technologies. The versatility of biopolymer composites with different electrical properties enables their applications in resistive, capacitive, and piezoelectric sensors, thus enhancing their potentials in healthcare, environmental monitoring, and consumer electronics. Here, we review an advancement of biopolymer composites in sensor technology, such as piezoresistive strain sensors used in structural health monitoring and a novel biochemical oxygen demand (BOD) biosensor for water monitoring. Integrating biopolymer composites into electrical biosensors has demonstrated promising results in detecting various substances, including moisture content in soil and model pollutants. Furthermore, their utilization in biopolymer-bound soil composites for building materials holds potential implications for sustainable construction practices. In summary, the incorporation of biopolymer composites in sensing applications paves the pathway towards developing smart and sustainable cities. As research continues, these materials are expected to play an increasingly significant role in sensor technology, providing eco-friendly solutions for challenges in civil engineering, environmental monitoring, and beyond. Furthermore, the potential for biopolymer composites to contribute to a more sustainable and interconnected world is considerable, making them a promising avenue for future sensor manufacturing and Internet of Things (IoT) applications.

Graphical Abstract

The advancement of sustainable biopolymer composites for sensors is comprehensively reviewed with their manufacturing and applications in smart cities.

Transition metal selenides are considered reliable anode materials for sodium-ion batteries (SIBs) on account of their commendable sodium storage capability. Yet they still face problems such as substantial volume amplification and unsatisfied conductivity which are detrimental to the circulation performance of the battery. In view of this, nitrogen-doped carbon (NC) packaged ZnSe/CoSe heterostructures (ZnSe/CoSe@NC) octahedron are rationally designed in this work. The NC capsulated heterostructures octahedron could substantially mitigate the issues of volume expansion and low conductivity for transition metal selenides. Additionally, the rich phase boundary derived from ZnSe/CoSe heterostructured interfaces yields numerous active sites for sodium ions and the formed electric field inside ZnSe/CoSe heterostructure can largely boost charge transfer. Most importantly, the unique heterostructure endows ZnSe/CoSe@NC with relatively stronger sodium adsorption, leading to long cycling stability with a reversible capacity of 289 mAh g⁻¹ underneath 900 cycles at 1 A g⁻¹. Given the pseudocapacitance effect of ZnSe/CoSe@NC in SIBs, a sodium ion capacitor (SIC) on the basis of ZnSe/CoSe@NC capacitor-type anode and Na₂FePO₄F (NFPF) battery-type cathode is rationally conceived and features high energy densities of 209.4 and 80.4 Wh kg⁻¹ at 240 and 4000 W kg⁻¹. The findings offer a promising pathway toward developing advanced energy storage devices with enhanced cycling stability and high energy density.

Transparent conductors (TCs) are applied in electromagnetic interference shielding and transparent electronic heaters due to their superior optoelectronic performance. Herein, a bio-template-based self-assembly strategy for silver nanowires (AgNWs) is employed to create novel “island-like” AgNW cluster morphologies, distinguishing from traditional random or circular shapes of AgNWs on PEN substrate. The unique structure ensures multidimensional pathways for free electron migration while concentrating visible light channels. Utilizing ultrasonic spray coating, AgNW random networks cover the clusters, bridge inter-cluster gaps, and ensure outstanding optoelectronic performance. Employing patterned self-assembled AgNWs combined with random networks marks a pioneering approach to achieving precise tunable electromagnetic interference shielding efficiency (EMI SE) in the X-band and optical transmittance, accommodating the diverse needs of various environments. The composite structure, featuring bottomed AgNW clusters and topped AgNW random networks (CRS), displays high transmittance with single-layer coating, achieving a remarkable figure of merit (FoM) of 15,481 (T@550 nm = 99.90%, Rs = 25.26 Ω/sq). This configuration also provides EMI shielding of 20.04 dB in the X-band, meeting commercial standards. Additional layers enhance the CRS films’ optoelectronic stability accompanied by tunable EMI shielding and excellent Joule heating performance.

Biofilms pose significant challenges in various fields, including food, healthcare, and environmental industries, where they compromise safety, quality, and operational efficiency. Understanding their behavior, evaluating antimicrobial efficacy, developing control strategies, and implementing monitoring systems are crucial steps in mitigating biofilm-related risks. This review explores the integration of rheology and atomic force microscopy techniques as powerful tools for addressing these challenges. Rheological models provide insights into biofilm viscoelastic properties, aiding in monitoring and predicting their behavior under diverse environmental conditions. From bulk rheological characterizations to micro-scale measurements, studies elucidate the complex interplay between environmental factors and biofilm development, informing strategies for disinfection and product optimization. AFM enables visualization of biofilm morphology, quantification of surface roughness, and probing of mechanical interactions at the nanoscale. Integration with other analytical techniques offers comprehensive insights into biofilm structure–function relationships, guiding innovative biofilm management strategies. Current applications span antimicrobial effectiveness assessments, biofilm control strategy design, and monitoring of biofilm contamination across industries. Leveraging interdisciplinary approaches holds promising potential to deepen our understanding of biofilms and develop more effective interventions, safeguarding product quality and human health. This review underscores the pivotal role of rheology and AFM in characterizing biofilms and addressing biofilm-related challenges in these fields, where continued research and innovation are essential for advancing our understanding and enhancing control strategies.

Graphic Abstract

With the advancement of science technology and the expansion of application area, the study and development of sensor materials and facilities has become a hot spot in today’s scientific community. As a device that can convert physical quantity, chemical properties, and biological characteristics into electrical signals, a sensor is widely used in environmental monitoring, medical diagnosis, industrial automation, and many other fields. Therefore, the study and development of sensor materials and devices not only helps to enhance the performance and sensitivity of sensors but also provides a feasible solution for solving practical problems. This work proposes a brief summary of the different classifications and applications of flexible sensor materials, as well as an outlook on their development direction and application prospects.

Graphical abstract

This work provides a brief overview of the different classifications and applications of flexible sensor materials, as well as an outlook on their development direction and application prospects.

Flexible sensors, made from flexible electronic materials, are of great importance in the medical field due to the rising prevalence of cardiovascular and cerebrovascular diseases. Studies have demonstrated that timely diagnosis and continuous monitoring of relevant physiological signals can be beneficial in preventing such conditions. Although traditional rigid monitoring sensors are still widely used for medical monitoring, the EMG, ECG, and EEG signals they obtain are often significantly affected by motion artifacts and noise. Therefore, the significance of wearable smart monitoring devices based on flexible electronic materials cannot be overstated. Numerous researchers have been working tirelessly for this purpose, exploring solutions from various angles, including material choice, circuit design, and algorithmic processing. This paper begins by analyzing the causes of motion artifacts in medical smart monitoring devices. Next, it introduces the application of flexible materials and flexible electronic materials in several aspects, along with the work of some representative flexible sensors. Following this, it discusses materials selection and device designs (e.g., accelerometers, gyroscopes, differential circuits, etc.) and algorithmic approaches for eliminating motion artifacts. Finally, an outlook on motion artifact removal techniques from the perspectives of more in-depth material development, structural design, and machine learning is provided. The purpose of this paper is to offer a comprehensive overview of current motion artifact removal techniques and materials, aiming to encourage further research and effectively address the key problem of signal acquisition accuracy in smart biomonitoring.

Graphical Abstract

TOC: Motion artifact occurrence state [40, 120]. Two methods of motion artifact removal or attenuation states are now commonly used: device design [30, 109] and algorithm development [115]. Future development focusing on machine learning and AI. [136]

In this study, poly(vinyl alcohol) (PVA) in a water solution was mixed with CNC suspensions in 4:1 and 3:2 weight ratios (w/w) and electrospun (ES) into aligned composite fiber mats. The electrospun mats were mechanically cut into high aspect ratio nanofibers (PVA:CNC-nf) and used as reinforcement in melt compounded thermoplastic poly(lactic acid) (PLA). A control PLA composite, containing neat electrospun PVA fibers (PVA-nf) and electrosprayed CNC nanoparticles (CNC-np), was produced for each composite fiber ratio. The electrospun nanofibers (ESNFs) were observed to maintain their morphology without exhibiting agglomeration or void formation in the PLA matrix. Composites containing 15 wt.% 4:1-nf improved tensile strength and stiffness of the PLA by 21% and 30%, while reducing strain at break by 7%, and increased PLA impact strength by 54%. In comparison, the 12 wt.% neat PVA-nf improved the PLA tensile strength and stiffness by 19% and 8%, respectively, while increasing tensile strain at break by 24% and impact strength by 30%. Toughness analysis indicated that the neat PVA-nf improved PLA specific tensile strength, despite the 4:1-nf absorbing more impact energy. Flexural strength improved slightly with the 3:2-nf, but flexural stiffness generally decreased, apart from 15% and 7.5% filled 4:1-nf and 3:2-nf filled PLA composites. Mechanical improvements were attributed to the electrospun reinforcement fibers’ nanometer dimensions and interfacial compatibility, based on by the shift to bound hydroxyl groups detected in the Fourier transform infrared spectroscopy (FTIR) analysis for the PLA composites.

Safeguarding aquatic ecosystems and human health requires effective methods for removing pollutants. Mercury (Hg) is a very toxic pollutant with a global presence and is highly mobile and persistent. Here, innovative materials were prepared for separating Hg(II) from water, and the mechanisms underlying the efficient uptake of Hg species have been investigated. The sorbents include silver (Ag) nanoparticles and multilayered Ti₃C₂T_x MXene, both incorporated into the structure of a three-dimensional polyethyleneimine porous cryogel (PEI) that acts as a scaffold holding and exposing nano active sites involved in the removal of Hg. Specifically, Ag particles were deposited onto MXene phases, and the resulting composite was embedded in the macroporous PEI polymer (PEI/MXene@Ag cryogel). The composite has beneficial properties regarding Hg removal: 99% of Hg was separated from waste within 24 h in batch studies. The maximum removal capacity of Hg reached 875 mg/g from HgCl₂, and 761 mg/g and 1280 mg/g from Hg(OAc)₂ and Hg(NO₃)₂ salts by PEI/MXene@Ag. The Hg uptake stems from the composite’s relatively large specific surface area, layered porous channels, and highly dispersed Ag nanoparticles in the multilayered Ti₃C₂T_x MXene. The matrix in the water samples that were treated with the composite did not hinder the uptake of Hg by PEI/MXene@Ag. The high effectiveness achieved for the removal of Hg, combined with rapid adsorption kinetics, high efficiency, and selectivity, positions it as an efficient solution. Future work should address upscaling its preparation for increasing readiness towards mitigating Hg in surface water.

This study focuses on the corrosion behaviors of an as-cast Al_0.75CoCr_1.25FeNi high entropy alloy (HEA) in 0.5 mol/L H₂SO₄ solution. The results showed that the HEA exhibited mixed column dendrite and inter-dendrite structures composed of face-centered cubic (FCC) phase, body-centered cubic (BCC) phase, and ordered BCC phase (B2). The corrosion resistance of the HEA in 0.5 mol/L H₂SO₄ solution was inferior to that of 316L stainless steel (SS); the HEA displayed an incomplete capacitive reactance arc at higher frequencies and an inductive reactance arc at lower frequencies during the electrochemical impedance spectroscopy test. The immersion experiments demonstrated an electrical potential difference between the Ni–Al-rich phase and the Fe-Co-Cr-rich phase of the HEA, resulting in micro-galvanic corrosion. This micro-galvanic corrosion prefers on the B2 (Ni–Al-rich) phase of the HEA. Moreover, the FCC phase and BCC1 phase of HEA corroded with the prolongation of immersion time. The surface of HEA has a loose and porous corrosion product film due to its relatively high percentage of Al₂O₃. Additionally, the ratio of Cr₂O₃/(Cr + Cr(OH)₃) in the corrosion product film decreased with the increase of immersion time.

Graphical Abstract

Al_0.75CoCr_1.25FeNi high entropy alloy exhibited mixed column dendrite and inter-dendrite structures composed of face-centered cubic (FCC) phase, body-centered cubic (BCC) phase, and ordered BCC phase (B2). The corrosion resistance of the high entropy alloy in 0.5 mol/L H₂SO₄ solution was inferior to that of 316L stainless steel.

Regulating the grain boundaries (GBs) via solute segregation provides a viable pathway to design stable nanocrystalline metals. This study investigates the segregation tendencies of X (X = In, Cr, Ca, Co, Zn, Ag, Zr, and Sn) at the potential sites of Cu Σ11 [110](1(overline{1})3) GB, as well as the co-segregation behavior of Y (Y = Cr and Co) at the Zr- and Ca-segregated Cu GBs, using first-principles calculations. Our results indicate that Cr and Co lack a thermodynamic driving force for segregating to Cu GBs, unlike other elements possessing GB segregation tendencies. The co-segregation calculations show that the presence of Zr at Cu GB can induce the segregation of Cr and Co. In comparison to the single-solute segregation of Zr, Cr, and Co, Zr-Co and Zr-Cr co-segregations exhibit synergistic enhancing effect on the GB thermodynamic stability. Regarding to the enhancement of GB fracture strength, Zr-Co co-segregation shows antagonistic effect, whereas Zr-Cr co-segregation demonstrates synergistic action. This work sheds light on accurately regulating the GB stability and strength of nanograined Cu alloys based on GB segregation.