Nano Materials Science最新文献

This review explores glucose monitoring and management strategies, emphasizing the need for reliable and user-friendly wearable sensors that are the next generation of sensors for continuous glucose detection. In addition, examines key strategies for designing glucose sensors that are multi-functional, reliable, and cost-effective in a variety of contexts. The unique features of effective diabetes management technology are highlighted, with a focus on using nano/biosensor devices that can quickly and accurately detect glucose levels in the blood, improving patient treatment and control of potential diabetes-related infections. The potential of next-generation wearable and touch-sensitive nano biomedical sensor engineering designs for providing full control in assessing implantable, continuous glucose monitoring is also explored. The challenges of standardizing drug or insulin delivery doses, low-cost, real-time detection of increased blood sugar levels in diabetics, and early digital health awareness controls for the adverse effects of injectable medication are identified as unmet needs. Also, the market for biosensors is expected to expand significantly due to the rising need for portable diagnostic equipment and an ever-increasing diabetic population. The paper concludes by emphasizing the need for further research and development of glucose biosensors to meet the stringent requirements for sensitivity and specificity imposed by clinical diagnostics while being cost-effective, stable, and durable.

Aqueous Zn batteries are promising candidates for grid-scale renewable energy storage. Foil electrodes have been widely investigated and applied as anode materials for aqueous Zn batteries, however, they suffer from limited surface area and severe interfacial issues including metallic dendrites and corrosion side reactions, limiting the depth of discharge (DOD) of the foil electrode materials. Herein, a low-temperature replacement reaction is utilized to in-situ construct a three-dimensional (3D) corrosion-resistant interface for deeply rechargeable Zn foil electrodes. Specifically, the deliberate low-temperature environment controlled the replacement rate between polycrystalline Zn metal and oxalic acid, producing a Zn foil electrode with distinct 3D corrosion-resistant interface (3DCI-Zn), which differed from conventional two-dimensional (2D) protective structure and showed an order of magnitude higher surface area. Consequently, the 3DCI-Zn electrode exhibited dendrite-free and anti-corrosion properties, and achieved stable plating/stripping performance for 1000 ​h at 10 ​mA ​cm⁻² and 10 mAh cm⁻² with a remarkable DOD of 79 ​%. After pairing with a MnO₂ cathode with a high areal capacity of 4.2 mAh cm⁻², the pouch cells delivered 168 ​Wh L⁻¹ and a capacity retention of 89.7 % after 100 cycles with a low negative/positive (N/P) ratio of 3:1.

Temperature regulating fibers (TRF_s) with high enthalpy and high form stability are the key factors for thermal management. However, the enthalpies of most TRF_s are not high, and the preparation methods are still at the laboratory scale. It remains a great challenge to use industrial spinning equipment to achieve continuous processing of TRF_s with excellent thermal and mechanical properties. Here, polyamide 6 (PA6) based TRF_s with a sheath-core structure were prepared by bicomponent melt-spinning. The sheath-core TRF (TRF_sc) are composed of PA6 as sheath and functional PA6 as core, which are filled with the shape stable phase change materials (ssPCM), dendritic silica@polyethylene glycol (SiO₂@PEG). With the aid of the sheath structure, the filling content of SiO₂@PEG can reach 30 ​%, so that the enthalpy of the TRF_s can be as high as 21.3 ​J/g. The ultra-high enthalpy guarantees the temperature regulation ability during the alternating process of cooling and heating. In hot environment, the temperature regulation time is 6.59 ​min, and the temperature difference is 12.93 ​°C. In addition, the mechanical strength of the prepared TRF_sc reaches 2.26 cN/dtex, which can fully meet its application in the field of thermal management textiles and devices to manage the temperature regulation of the human body or precision equipment, etc.

Single-atom catalysts (SACs) are gaining popularity in catalytic reactions due to their nearly 100 ​% atomic utilization and defined active sites, which provide great convenience for studying the catalytic mechanism of catalysts. However, SACs still present challenges such as complex formation processes, low loading and easy agglomeration of catalysts. Herein, we systematically discuss the synthesis methods for SACs, including co-precipitation, impregnation, atomic layer deposition, pyrolysis and Anti-Ostwald ripening etc. Various techniques for characterizing single-atom catalysts (SACs) are described in detail. The utilization of individual atoms in various photocatalytic reactions and their mechanisms of action in different reactions are explained. The purpose of this review is to introduce single-atom synthesis methods, characterization techniques, specific catalytic action and their applications in the direction of photocatalysis, and to provide a reference for the industrialization of photocatalytic single-atoms, which is currently impossible, in the hope of promoting further development of photocatalytic single-atoms.

Graphene-doped CuO (rGO-CuO) nanocomposites with flower shapes were prepared by an improved solvothermal method. The samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy and UV–visible spectroscopy. The active species in the degradation reaction of rGO-CuO composites under ultrasonic irradiation were detected by electron paramagnetic resonance. On the basis of comparative experiments, the photodegradation mechanisms of two typical dyes, Rhodamine B (Rh B) and methyl orange (MO), were proposed. The results demonstrated that the doped CuO could improve the degradation efficiency. The catalytic degradation efficiency of rGO-CuO (2:1) to rhodamine B (RhB) and methyl orange (MO) reached 90 ​% and 87 ​% respectively, which were 2.1 times and 4.4 times of the reduced graphene oxide. Through the first-principles and other theories, we give the reasons for the enhanced catalytic performance of rGO-CuO: combined with internal and external factors, rGO-CuO under ultrasound could produce more hole and active sites that could interact with the OH· in pollutant molecules to achieve degradation. The rGO-CuO nanocomposite has a simple preparation process and low price, and has a high efficiency of degrading water pollution products and no secondary pollution products. It has a low-cost and high-efficiency application prospect in water pollution industrial production and life.

Carbon nanotubes (CNTs) with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon aerogels. However, there remains a major challenge for achieving the on-demand shaping of carbon aerogels with tailored micro-nano structural textures and geometric features. Herein, a facile extrusion 3D printing strategy has been proposed for fabricating CNT-assembled carbon (CNT/C) aerogel nanocomposites through the extrusion printing of pseudoplastic carbomer-based inks, in which the stable dispersion of CNT nanofibers has been achieved relying on the high viscosity of carbomer microgels. After extrusion printing, the chemical solidification through polymerizing RF sols enables 3D-printed aerogel nanocomposites to display high shape fidelity in macroscopic geometries. Benefiting from the micro-nano scale assembly of CNT nanofiber networks and carbon nanoparticle networks in composite phases, 3D-printed CNT/C aerogels exhibit enhanced mechanical strength (fracture strength, 0.79 ​MPa) and typical porous structure characteristics, including low density (0.220 ​g ​cm⁻³), high surface area (298.4 ​m² ​g⁻¹), and concentrated pore diameter distribution (∼32.8 ​nm). More importantly, CNT nanofibers provide an efficient electron transport pathway, imparting 3D-printed CNT/C aerogel composites with a high electrical conductivity of 1.49 ​S ​cm⁻¹. Our work would offer feasible guidelines for the design and fabrication of shape-dominated functional materials by additive manufacturing.

This research investigates the hydrothermal synthesis and annealing duration effects on nickel sulfide (NiS₂) quantum dots (QDs) for catalytic decolorization of methylene blue (MB) dye and antimicrobial efficacy. QD size increased with longer annealing, reducing catalytic activity. UV–vis, XRD, TEM, and FTIR analyses probed optical, structural, morphological, and vibrational features. XRD confirmed NiS2's anorthic structure, with crystallite size growing from 6.53 to 7.81 ​nm during extended annealing. UV–Vis exhibited a bathochromic shift, reflecting reduced band gap energy (Eg) in NiS₂. TEM revealed NiS₂ QD formation, with agglomerated QD average size increasing from 7.13 to 9.65 ​nm with prolonged annealing. Pure NiS₂ showed significant MB decolorization (89.85%) in acidic conditions. Annealed NiS2 QDs demonstrated notable antibacterial activity, yielding a 6.15 ​mm inhibition zone against Escherichia coli (E. coli) compared to Ciprofloxacin. First-principles computations supported a robust interaction between MB and NiS₂, evidenced by obtained adsorption energies. This study highlights the nuanced relationship between annealing duration, structural changes, and functional properties in NiS₂ QDs, emphasizing their potential applications in catalysis and antibacterial interventions.

An efficient room-temperature self-powered, broadband (300 ​nm–1100 nm) photodetector based on a CuO–TiO₂/TiO₂/p-Si(100) heterostructure is demonstrated. The CuO–TiO₂ nanocomposites were grown in a two-zone horizontal tube furnace on a 40 ​nm TiO₂ thin film deposited on a p-type Si(100) substrate. The CuO–TiO₂/TiO₂/p-Si(100) devices exhibited excellent rectification characteristics under dark and individual photo-illumination conditions. The devices showed remarkable photo-response under broadband (300–1100 ​nm) light illumination at zero bias voltage, indicating the achievement of highly sensitive self-powered photodetectors at visible and near-infrared light illuminations. The maximum response of the devices is observed at 300 ​nm for an illumination power of 10 ​W. The response and recovery times were calculated as 86 ​ms and 78 ​ms, respectively. Moreover, under a small bias, the devices showed a prompt binary response by altering the current from positive to negative under illumination conditions. The main reason behind this binary response is the low turn-on voltage and photovoltaic characteristics of the devices. Under illumination conditions, the generation of photocurrent is due to the separation of photogenerated electron-hole pairs within the built-in electric field at the CuO–TiO₂/TiO₂ interface. These characteristics make the CuO–TiO₂/TiO₂ broadband photodetectors suitable for applications that require high response speeds and self-sufficient functionality.

Recently, a Schwarz crystal structure with curved grain boundaries (GBs) constrained by twin-boundary (TB) networks was discovered in nanocrystalline Cu through experiments and atomistic simulations. Nanocrystalline Cu with nanosized Schwarz crystals exhibited high strength and excellent thermal stability. However, the grain-size effect and associated deformation mechanisms of Schwarz nanocrystals remain unknown. Here, we performed large-scale atomistic simulations to investigate the deformation behaviors and grain-size effect of nanocrystalline Cu with Schwarz crystals. Our simulations showed that similar to regular nanocrystals, Schwarz nanocrystals exhibit a strengthening-softening transition with decreasing grain size. The critical grain size in Schwarz nanocrystals is smaller than that in regular nanocrystals, leading to a maximum strength higher than that of regular nanocrystals. Our simulations revealed that the softening in Schwarz nanocrystals mainly originates from TB migration (or detwinning) and annihilation of GBs, rather than GB-mediated processes (including GB migration, sliding and diffusion) dominating the softening in regular nanocrystals. Quantitative analyses of simulation data further showed that compared with those in regular nanocrystals, the GB-mediated processes in Schwarz nanocrystals are suppressed, which is related to the low volume fraction of amorphous-like GBs and constraints of TB networks. The smaller critical grain size arises from the suppression of GB-mediated processes.