Advances in graphene-based 2D materials for tendon, nerve, bone/cartilage regeneration and biomedicine.

Two-dimensional (2D) materials, especially graphene-based materials, have important implications for tissue regeneration and biomedicine due to their large surface area, transport properties, ease of functionalization, biocompatibility, and adsorption capacity. Despite remarkable progress in the field of tissue regeneration and biomedicine, there are still problems such as unclear long-term stability, lack of in vivo experimental data, and detection accuracy. This paper reviews recent applications of graphene-based materials in tissue regeneration and biomedicine and discusses current issues and prospects for the development of graphene-based materials with respect to promoting the regeneration of tendons, neuronal cells, bone, chondrocytes, blood vessels, and skin, as well as applications in sensing, detection, anti-microbial activity, and targeted drug delivery.

SolunumWear: A smart textile system for dynamic respiration monitoring across various postures.

We introduce SolunumWear, a multi-sensory e-textile system designed for respiration in daily life settings, addressing the gap in continuous, real-world respiration event monitoring. Leveraging a textile pressure sensor belt to capture chest movements and a wireless data acquisition system, SolunumWear offers a promising solution for both medical and wellness applications. The system's efficacy was evaluated through a human study involving 10 healthy adults (six female and four male) across various breathing rates and postures, demonstrating a strong correlation (R value = 0.836) with the gold-standard system. The study highlights the system's computational and communication efficiencies, with latencies of approximately 4.84 s and 2.13 ms, respectively. These findings highlight the efficacy of SolunumWear as a wireless, wearable technology for respiration monitoring in daily settings. This research contributes to the expanding body of knowledge on smart textile-based health monitoring technologies, demonstrating its potential to provide reliable respiratory data in real-world environments.

Proton conductivity of the protein-based velvet worm slime.

The properties of complex bodily fluids are linked to their biological functions through natural selection. Velvet worms capture their prey by ensnaring them with a proteinaceous fluid (slime). We examined the electrical conductivity of slime and found that dry slime is an insulator. However, its conductivity can increase by up to 106 times in its hydrated state, which can be further increased by an order in magnitude under acidic hydration (pH ≈ 2.3). The transient current measured using ion-blocking electrodes showed a continuous decay for up to 7 h, revealing slime's nature as a proton conducting material. Slime undergoes a spontaneous fibrilization process producing high aspect ratio ≈ 105 fibers that exhibit an average conductivity ≈2.4 ± 1.1 mS cm-1. These findings enhance our understanding of slime as a natural biopolymer and provide molecular-level guidelines to rationally design biomaterials that may be employed as hygroscopic conductors.

Binder assisted graphene derivatives as lubricants in copper: Improved tribological performance for industrial application.

Originally derived from graphite, high-quality single-layer graphene is an excellent anti-wear and -friction additive in metal matrix. Here, the tribological performance of 3 different commercialized graphene derivatives (e.g., graphene oxide [GO], reduced graphene oxide [RGO], and graphene nanoplatelet [GNP]) as additives in a Cu matrix, were investigated from an industrial perspective. To increase the interaction of graphene derivatives with Cu particles, and addressing the aggregation problem of the graphene derivatives, different binders (polyvinyl alcohol [PVA] and cellulose nanocrystals [CNC]) were introduced into the system. Benefiting from such a strategy, a uniform distribution of the graphene derivatives in Cu matrix was achieved with graphene loading up to 5 wt %. After high-temperature sintering, the graphene is preserved and well distributed in the Cu matrix. It was found that the GNP-containing sample shows the most stable friction coefficient behavior. However, GO and RGO also improve the tribological performance of Cu under different circumstances.

Angular dependent terahertz emission from the interplay between nanocrystal diamond film and plasmonic metasurface.

Composite structures integrated with metasurfaces and nonlinear films have emerged as alternative candidates to enhance nonlinear response. The cooperative interaction between the two components is complicated. Herein, a split-ring resonator (SRR)-type metasurface was fabricated on a free-standing nanocrystal diamond (NCD) film utilizing electron beam lithography, electron beam evaporation, and a lift-off process. The terahertz (THz) radiation from the SRR-NCD under normal incidence originates from the high-order magnetic resonance of SRR because the NCD film cannot produce detectable THz radiation at this incident angle. As increasing the incident angle, the contribution of the THz radiation from the NCD film gradually increases until reaching 40° incident angle limitation. The results indicate that this angular-dependent THz radiation is induced by the interplay between the NCD film and SRR. This study offers a new approach to investigate nonlinear processes in composite structures.

Perovskite-based photodetector for real-time and quantitative monitoring of sports motion.

Reliable monitoring the movement amplitude and dynamics during sports exercise is significant for improving training results and preventing training wound. Here, we present a printed perovskite-based photodetector for real-time and quantitative monitoring of sports motion. The ordered nucleation and growth of perovskite crystals are regulated by the 4-acetamidothiophenol (AMTP) at the interface, which promotes the size of perovskite crystals into the micrometer. Benefiting from the uniformity of the AMTP-regulated MAPbI3, the as-prepared photodetector gives great photocurrent response under indoor light or outdoor light. During the exercise, real-time monitoring sports motion is achieved through detecting the illumination changing of photodetectors attaching on the wrist and ankles. Moreover, twelve kinds of common sports can be quantitatively analyzed with the detection of illumination changing on the photodetector. Such photodetector provides an efficient measurement method of wearable electronics for sports monitoring.

Development and clinical validation of a miniaturized finger probe for bedside hemodynamic monitoring.

Our aim is to develop a blood pressure (BP) measurement technology that could be integrated into a finger-worn pulse oximeter, eliminating the need for a brachial cuff. We present a miniature cuffless tonometric finger probe system that uses the oscillometric method to measure BP. Our approach uses a motorized press that is used to apply pressure to the fingertip to measure BP. We verified the functionality of the device in a clinical trial (n = 43) resulting in systolic and diastolic pressures ((mean ± SD) mmHg) of (-3.5 ± 8.4) mmHg and (-4.0 ± 4.4) mmHg, respectively. Comparison was made with manual auscultation (n = 26) and automated cuff oscillometry (n = 18). In addition to BP, we demonstrated the ability of the device to assess arterial stiffness (n = 18) and detect atrial fibrillation (n = 6). We were able to introduce a sufficiently small device that could be used for convenient ambulatory measurements with minimal discomfort.

Multimode microdimer robot for crossing tissue morphological barrier.

Swimming microrobot energized by magnetic fields exhibits remotely propulsion and modulation in complex biological experiment with high precision. However, achieving high environment adaptability and multiple tasking capability in one configuration is still challenging. Here, we present a strategy that use oriented magnetized Janus spheres to assemble the microdimer robots with two magnetic distribution configurations of head-to-side configuration (HTS-config) and head-to-head configuration (HTH-config), achieving performance of multiple tasks through multimode transformation and locomotion. Modulating the magnetic frequency enables multimode motion transformation between tumbling, rolling, and swing motion with different velocities. The dual-asynchronization mechanisms of HTS-config and HTH-config robot dependent on magnetic dipole-dipole angle are investigated by molecular dynamic simulation. In addition, the microdimer robot can transport cell crossing morphological rugae or complete drug delivery on tissues by switching motion modes. This microdimer robot can provide versatile motion modes to address environmental variations or multitasking requirements.

An ultra-small integrated CO2 infrared gas sensor for wearable end-tidal CO2 monitoring.

Human physiological metabolic status can be obtained by monitoring exhaled CO2 concentration, but current CO2 sensors have disadvantages such as large size, high power consumption, and slow response time, which limit their application in wearable devices and portable instruments. In this article, we report a small size, good performance, and large range CO2 infrared gas sensor that integrates a high emissivity MEMS emitter chip, a high detectivity thermopile chip, and a high coupling efficiency optical chamber to achieve high efficiency optical-thermal-electrical conversion. Compared with typical commercial sensors, the size of the sensor can be reduced by approximately 80% to only 10 mm × 10 mm × 6.5 mm, with the advantages of low power consumption and fast response speed. Further, a monitoring system for end-tidal CO2 concentration installed on a mask was developed using this sensor, and good results were achieved.

Roadmap for phase change materials in photonics and beyond.

Phase Change Materials (PCMs) have demonstrated tremendous potential as a platform for achieving diverse functionalities in active and reconfigurable micro-nanophotonic devices across the electromagnetic spectrum, ranging from terahertz to visible frequencies. This comprehensive roadmap reviews the material and device aspects of PCMs, and their diverse applications in active and reconfigurable micro-nanophotonic devices across the electromagnetic spectrum. It discusses various device configurations and optimization techniques, including deep learning-based metasurface design. The integration of PCMs with Photonic Integrated Circuits and advanced electric-driven PCMs are explored. PCMs hold great promise for multifunctional device development, including applications in non-volatile memory, optical data storage, photonics, energy harvesting, biomedical technology, neuromorphic computing, thermal management, and flexible electronics.

Sweat and odor in sportswear - A review.

Sportswear worn next to the skin is easily soaked by sweat and may become a breeding ground for the microbiome, thus a source of malodor. Malodor can cause social embarrassment and discomfort to both wearer and others. Given the risks current deodorant products pose to nature and human life, the development of sustainable textiles for odor control comes to the forefront. This review introduces the odor-generating mechanism in clothing from the perspectives of perspiration composition and cutaneous microbiome. With the knowledge of the significant role of sweat in odor formation, the sweat distribution of the human body, measurement techniques, and advanced technologies developed for quick-dry function are presented in the second part. Lastly, odor management in sportswear is evaluated, covering the odor-assessing techniques, the effects of various textile materials, and emerging solutions in terms of antibacterial treatment, adsorbent materials, and photocatalytic degradations of odorous compounds. Overall, it is of both personal and social value to develop novel textile materials with odor-control functions by making use of natural materials and fabric designs.

Stabilization of low-cost phase change materials for thermal energy storage applications.

Sodium sulfate decahydrate (Na2SO4.10H2O, SSD), a low-cost phase change material (PCM), can store thermal energy. However, phase separation and unstable energy storage capacity (ESC) limit its use. To address these concerns, eight polymer additives-sodium polyacrylate (SPA), carboxymethyl cellulose (CMC), Fumed silica (SiO2), potassium polyacrylate (PPA), cellulose nanofiber (CNF), hydroxyethyl cellulose (HEC), dextran sulfate sodium (DSS), and poly(sodium 4-styrenesulfonate) (PSS)-were used to explore several stabilization mechanisms. The ESC of PCMs deteriorated when thickeners, SPA, PPA, and CNF, were added. DSS-modified PCMs exhibited greater stability up to 150 cycles. Rheology measurements indicated that DSS did not impact SSD viscosity significantly during stabilization. Dynamic light scattering showed that DSS reduces SSD particle size and electrostatically suspends salt particles in a stable homogeneous solution, avoiding phase separation. This study proposes a promising method to improve the thermal stability of salt hydrate PCMs by utilizing polyelectrolyte-salt hydrate mixture for thermal energy storage applications.

Prospective applications of two-dimensional materials beyond laboratory frontiers: A review.

The development of nanotechnology has been advancing for decades and gained acceleration in the 21st century. Two-dimensional (2D) materials are widely available, giving them a wide range of material platforms for technological study and the advancement of atomic-level applications. The design and application of 2D materials are discussed in this review. In order to evaluate the performance of 2D materials, which might lead to greater applications benefiting the electrical and electronics sectors as well as society, the future paradigm of 2D materials needs to be visualized. The development of 2D hybrid materials with better characteristics that will help industry and society at large is anticipated to result from intensive research in 2D materials. This enhanced evaluation might open new opportunities for the synthesis of 2D materials and the creation of devices that are more effective than traditional ones in various sectors of application.

Progress and challenges of emerging MXene based materials for thermoelectric applications.

To realize sustainable development, more and more countries forwarded carbon neutrality goal. Accordingly, improving the utilization efficiency of traditional fossil fuel is an effective strategy for this great goal. Keeping this in mind, developing thermoelectric devices to recover waste heat energy resulted in the consumption process of fuel is demonstrated to be promising. High performance thermoelectric devices require advanced materials. MXenes are a kind of 2D materials with a layered structure, which demonstrate excellent thermoelectric performance owing to their unique physical, mechanical, and chemical properties. Also, substantial achievement has been gained during the past few years in synthesizing MXene based materials for thermoelectric devices. In this review, the mainstream synthetic routes of MXene from etching MAX were summarized. Significantly, the current state and challenges of research on improving the performance of MXene based thermoelectrics are explored, including pristine MXene and MXene based composites.

Quantum view of Li-ion high mobility at carbon-coated cathode interfaces.

Lithium-ion batteries (LIBs) are among the most promising power sources for electric vehicles, portable electronics and smart grids. In LIBs, the cathode is a major bottleneck, with a particular reference to its low electrical conductivity and Li-ion diffusivity. The coating with carbon layers is generally employed to enhance the electrical conductivity and to protect the active material from degradation during operation. Here, we demonstrate that this layer has a primary role in the lithium diffusivity into the cathode nanoparticles. Positron is a useful quantum probe at the electroactive materials/carbon interface to sense the mobility of Li-ion. Broadband electrical spectroscopy demonstrates that only a small number of Li-ions are moving, and that their diffusion strongly depends on the type of carbon additive. Positron annihilation and broadband electrical spectroscopies are crucial complementary tools to investigate the electronic effect of the carbon phase on the cathode performance and Li-ion dynamics in electroactive materials.

Enhancing cycle life and usable energy density of fast charging LiFePO4-graphite cell by regulating electrodes' lithium level.

Range anxiety is a primary concern among present-day electric vehicle (EV) owners, which could be curtailed by maximizing the driving range per charge or reducing the charging time of the lithium-ion battery (LIB) pack. Maximizing the driving range is a multifaceted task as charging-discharging the LIB up to 100% of its nominal capacity is limited by the cell chemistry (voltage window) and cell operating conditions. Our studies on commercial LiFePO4/graphite cells show that a cycle life of 4320 is achieved at 4C rate with 80% SOC-100% DOD combination (12 min charging time), which is the highest among the works reported with this cell chemistry. Complete utilization of electrodes' lithium during cycling resulted in the lowest cycle life of 956. This study demonstrates LIB charging-discharging protocol enabling longer driving range with quicker charging times. Besides, it might endow promising possibilities of future EV LIB packs with reduced size/weight and high safety.

NEUTRON: Neural particle swarm optimization for material-aware inverse design of structural color.

Designing optical structures for generating structural colors is challenging because of the complex relationship between the optical structures and the color perceived by human eyes. Machine learning-based approaches have been developed to expedite this design process. However, existing methods solely focus on structural parameters of the optical design, which could lead to suboptimal color generation because of the inability to optimize the selection of materials. To address this issue, an approach known as Neural Particle Swarm Optimization is proposed in this paper. The proposed method achieves high design accuracy and efficiency on two structural color design tasks; the first task is designing environment-friendly alternatives to chrome coatings, and the second task concerns reconstructing pictures with multilayer optical thin films. Several designs that could replace chrome coatings have been discovered; pictures with more than 200,000 pixels and thousands of unique colors can be accurately reconstructed in a few hours.

Harvesting circuits for triboelectric nanogenerators for wearable applications.

Internet of Things (IoT) and recently Internet of Nano Things (IoNT) bear the promise of new devices able to communicate and assist our daily lives toward wearable technologies which demand a versatile integration such as in wireless body networks (WBN), sensing, and health monitorization. These must comply with stringent constraints on energy usage. Dimensions and complexity intensify the need for small and maintenance-free power sources. Environment energy harvesting and storage is an important approach to sustain operation for a long time. Triboelectric nanogenerators (TENGs) arise as a strong and promising solution to power the new field of outcoming self-sustainable devices, implantable, and wearable devices. They can transform mechanical energy in different modes, have simple structures, and use vulgar and sustainable materials. This paper makes a review about TENGs technology, construction, materials, operation, and focus on strategies for harvesting circuits. Main challenges like efficiency, reliability, energy storage, and sustainability are discussed.

Flux upcycling of spent NMC 111 to nickel-rich NMC cathodes in reciprocal ternary molten salts.

The proper handling of end-of-life (EOL) lithium-ion batteries (LIBs) has become an urgent and challenging issue with the surging use of LIBs, in which recovering high-value cathodes not only relieves the pressure on the raw material supply chain but also minimizes environmental pollution. Beyond direct recycling of spent cathodes to their pristine states, the direct upcycling of spent cathodes to the next-generation cathodes is of great significance to maximize the value of spent materials and to sustain the fast development of LIBs. Herein, a "reciprocal ternary molten salts" (RTMS) system was developed to directly upcycle spent NMC 111 to Ni-rich NMCs by simultaneously realizing the addition of Ni and the relithiation of Li in spent NMC 111. After RTMS flux upcycling, the obtained Ni-rich NMCs exhibited an α-NaFeO2-type layered structure, restored Li content, and excellent performance, which is very similar to that of the pristine NMC 622.

Hyperbranched polymers as superior adsorbent for the treatment of dyes in water.

The effective control on environmental pollutants is crucial for the proper management of diverse environmental systems (e.g., soil, water, and air). In this respect, the utility of various functional materials such as hyperbranched polymers (HPs) has been recognized due to their great potentil as adsorbent for the mitigation of numerous environmental pollutants. Here, we highlight the latest progress achieved in the design and construction of HPs with high adsorption potentials. We focus on adsorption mechanisms, functionalization methods, the role of functional groups in adsorption capacity, and the choice of HPs in adsorption of cationic and anionic dyes. Recent published reports are reviewed to quantify and qualify the removal efficiency of pollutants through adsorption. We also evaluate the adsorbing efficiency of the constructed HPs and compared their performance with other such systems. The utilization potential of new materials (magnetic, polar, and biological) is highlighted along with the methods needed for their preparation and/or modification (surface, end-group, and zwitterionic) for the construction of efficient adsorbing systems. Finally, the advantages and limitations of adsorbing systems are described along with the existing challenges to help establish guidelines for future research. This article is thus expected to offer new path and guidance for developing advanced HP-based adsorbents.