Recent years witnessed a growing research interest in graphene-reinforced aluminum matrix composites (GRAMCs). Compared with conventional reinforcements of aluminum matrix composites (AMCs), graphene possesses many attractive characteristics such as extremely high strength and modulus, unique self-lubricating property, high thermal conductivity (TC) and electrical conductivity (EC), and low coefficient of thermal expansion (CTE). A lot of studies have demonstrated that the incorporation of graphene into Al or Al alloy can effectively enhance mechanical and physical properties of the Al matrix. The purpose of this work is aimed to trace recent development of GRAMCs. Initially, this paper covers a brief overview of fabrication methods of GRAMCs. Then, mechanical, tribological, thermal and electrical properties of recently developed GRAMCs are presented and discussed. Finally, challenges and corresponding solutions related to GRAMCs are reviewed.

Tungsten (W) has become the most promising plasma-facing material (PFM) in fusion reactor, and W still faces performance degradation caused by low-temperature brittleness, low recrystallization temperature, neutron irradiation effects, and plasma irradiation effects. The modification of W/W-based materials in terms of microstructure manipulation is needed, and such techniques to improve the performance of materials are the topics of hot research. Researchers have found that refining the grain can significantly improve the strength and the irradiation resistance of W/W-based materials. In this paper, novel approaches and technique routes, including the “bottom-up” powder metallurgy method and “top-down” severe plastic deformation method, are introduced to the fabrication of nanocrystalline W/W-based materials. The formation mechanisms of nanocrystalline W/W-based materials were revealed, and the nanostructure stabilization mechanisms were introduced. The mechanical properties of nanocrystalline W/W-based materials were tested, and the irradiation behaviors and performances were studied. The mechanisms of their high mechanical properties and excellent irradiation-damage resistance were illustrated. This article may provide an experimental and theoretical basis for the design and development of high-performance novel nanocrystalline W/W-based materials.

Hollow mesoporous silica nanoparticles (HMSNs) have become an attractive drug carrier because of their unique characteristics including stable physicochemical properties, large specific surface area and facile functionalization, especially made into intelligent drug delivery systems (DDSs) for cancer therapy. HMSNs are employed to transport traditional anti-tumor drugs, which can solve the problems of drugs with instability, poor solubility and lack of recognition, etc., while significantly improving the anti-tumor effect. And an unexpected good result will be obtained by combining functional molecules and metal species with HMSNs for cancer diagnosis and treatment. Actually, HMSNs-based DDSs have developed relatively mature in recent years. This review briefly describes how to successfully prepare an ordinary HMSNs-based DDS, as well as its degradation, different stimuli-responses, targets and combination therapy. These versatile intelligent nanoparticles show great potential in clinical aspects.

In this work, a sky-blue luminescent down-shifting (LDS) layer bis[(4,6-difluorophenyl)-pyridinato-N,C^2′]c(picolinate)iridium(III) (FIrpic) was inserted between tetraphenyldibenzoperiflanthene (DBP) and MoO₃ as UV-screen and sensitizer for small molecule DBP/C₆₀ based planar heterojunction (PHJ) solar cells. With 8-nm FIrpic the short circuit current (J_sc) and power conversion efficiency (PCE) of the device are enhanced by 28% and 15%, respectively, probably originating from the re-absorption of the photons emitted from FIrpic. The V_oc linearly increases over 1-nm FIrpic, ascribed to the deeper HOMO level of FIrpic than DBP, while the fill factor continuously declines from 3- to 10-nm FIrpic. The EQE spectra prove that the J_sc is mainly contributed by the photocurrent generated in DBP and C₆₀ layers. When the FIrpic thickness is 8 nm, the film surface is very uniform with the smallest water contact angle. The impedance spectroscopy demonstrates that the device resistance gradually increases from 4.1×10⁴ W (without FIrpic) to 4.6×10⁴ W (with 10-nm FIrpic) with the FIrpic thickness rise, simultaneously the device transits from the insulating state into the conductive state faster for the thin FIrpic layer than the thick layer.

With the rapid improvements in nanomaterials and imaging technology, great progresses have been made in diagnosis and treatment of diseases during the past decades. Fe₃O₄ magnetic nanoparticles (MNPs) with good biocompatibility and superparamagnetic property are usually used as contrast agent for diagnosis of diseases in magnetic resonance imaging (MRI). Currently, the combination of multiple imaging technologies has been considered as new tendency in diagnosis and treatment of diseases, which could enhance the accuracy and reliability of disease diagnosis and provide new strategies for disease treatment. Therefore, novel contrast agents used for multifunctional imaging are urgently needed. Fe₃O₄ MNPs are believed to be a potential candidate for construction of multifunctional platform in diagnosis and treatment of diseases. In recent years, there are a plethora of studies concerning the construction of multifunctional platform presented based on Fe₃O₄ MNPs. In this review, we introduce fabrication methods and modification strategies of Fe₃O₄ MNPs, expecting great improvements for diagnosis and treatment of diseases in the future.

We exploited a unique porous structure of the nano-covalent triazine polymer (NCTP) containing aggregation-induced emission (AIE) group to achieve controlled release and drug tracking in tumor acidic microenvironment. NCTP was synthesized by the Friedel–Crafts alkylation and the McMurry coupling reaction. It not only had strong doxorubicin (DOX)-loading capacity due to its high specific surface area and large pore volume, but also showed the significant cumulative drug release as a result of the pH response of triazine polymers. NCTP was induced luminescence after mass accumulation near tumor cells. Besides, it had excellent biocompatibility and obvious antineoplastic toxicity. The results demonstrate that NCTP as a utility-type drug carrier provides a new route for designing the multi-functional drug delivery platform.

Processing biomaterials into porous scaffolds for bone tissue engineering is a critical and a key step in defining and controlling their physicochemical, mechanical, and biological properties. Biomaterials such as polymers are commonly processed into porous scaffolds using conventional processing techniques, e.g., salt leaching. However, these traditional techniques have shown unavoidable limitations and several shortcomings. For instance, tissue-engineered porous scaffolds with a complex three-dimensional (3D) geometric architecture mimicking the complexity of the extracellular matrix of native tissues and with the ability to fit into irregular tissue defects cannot be produced using the conventional processing techniques. 3D printing has recently emerged as an advanced processing technology that enables the processing of biomaterials into 3D porous scaffolds with highly complex architectures and tunable shapes to precisely fit into irregular and complex tissue defects. 3D printing provides computer-based layer-by-layer additive manufacturing processes of highly precise and complex 3D structures with well-defined porosity and controlled mechanical properties in a highly reproducible manner. Furthermore, 3D printing technology provides an accurate patient-specific tissue defect model and enables the fabrication of a patient-specific tissue-engineered porous scaffold with pre-customized properties.

With the rapid development of wearable smart devices, many researchers have carried out in-depth research on the stretchable electrodes. As one of the core components for electronics, the electrode mainly transfers the electrons, which plays an important role in driving the various electrical devices. The key to the research for the stretchable electrode is to maintain the excellent electrical properties or exhibit the regular conductive change when subjected to large tensile deformation. This article outlines the recent progress of stretchable electrodes and gives a comprehensive introduction to the structures, materials, and applications, including supercapacitors, lithium-ion batteries, organic light-emitting diodes, smart sensors, and heaters. The performance comparison of various stretchable electrodes was proposed to clearly show the development challenges in this field. We hope that it can provide a meaningful reference for realizing more sensitive, smart, and low-cost wearable electrical devices in the near future.

Superamphiphobic surfaces have attracted the attention of researchers because of their broad application prospects. Currently, superamphiphobicity is primarily achieved by minimizing the solid–liquid contact area. Over the past few decades, researchers have primarily focused on using physical deposition methods to construct superamphiphobic surfaces using fine-sized nanoparticles (< 100 nm). However, porous hollow SiO₂ particles (PH-SiO₂), which are typically large spheres, have a highly hierarchical structure and can provide lower solid–liquid contact fractions than those provided by fine-sized particles. In this study, we used PH-SiO₂ as building blocks and combined them with poly (dimethylsiloxane) to construct a mechanically robust coating on fiber by spray-coating. After chemical vapor deposition treatment, the coating exhibited excellent superamphiphobicity and could repel various liquids, covering a wide range of surface tensions (27.4–72.0 mN·m⁻¹).

As a kind of essential hydrated salt phase change energy storage materials, mirabilite with high energy storage density and mild phase-transition temperature has excellent application potential in the problems of solar time and space mismatch. However, there are some disadvantages such as supercooling, substantial phase stratification and leakage problem, limiting its further applications. In this work, for the preparation of shaped mirabilite phase change materials (MPCMs), graphene (GO), sodium carboxymethyl cellulose (CMC), and carbon nanofibers (CNFs) were used as starting materials to prepare lightweight CMC/rGO/CNFs carbon aerogel (CGCA) as support with stable shape, high specific surface area, and well-arranged hierarchically porous structure. The results show that CGCA has regular layered plentiful pores and stable foam structure, and the pore and sheet interspersed structure in CGCA stabilizes PCMs via capillary force and surface tension. The hydrophilic aerogels supported MPCMs decrease mirabilite leaking and reduce supercooling to around 0.7‒1 °C. The latent heats of melting and crystallization of CGCA-supported mirabilite phase change materials (CGCA-PCMs) are 157.1 and 114.8 J·g⁻¹, respectively. Furthermore, after 1500 solid‒liquid cycles, there is no leakage, and the retention rate of crystallization latent heat is 45.32%, exhibiting remarkable thermal cycling stability.

The consumer demand for emerging technologies such as augmented reality (AR), autopilot, and three-dimensional (3D) internet has rapidly promoted the application of novel optical display devices in innovative industries. However, the micro/nanomanufacturing of high-resolution optical display devices is the primary issue restricting their development. The manufacturing technology of micro/nanostructures, methods of display mechanisms, display materials, and mass production of display devices are major technical obstacles. To comprehensively understand the latest state-of-the-art and trigger new technological breakthroughs, this study reviews the recent research progress of master molds produced using nanoimprint technology for new optical devices, particularly AR glasses, new-generation light-emitting diode car lighting, and naked-eye 3D display mechanisms, and their manufacturing techniques of master molds. The focus is on the relationships among the manufacturing process, microstructure, and display of a new optical device. Nanoimprint master molds are reviewed for the manufacturing and application of new optical devices, and the challenges and prospects of the new optical device diffraction grating nanoimprint technology are discussed.

Lithium–sulfur (Li‒S) battery has been considered as one of the most promising future batteries owing to the high theoretical energy density (2600 W·h·kg⁻¹) and the usage of the inexpensive active materials (elemental sulfur). The recent progress in fundamental research and engineering of the Li‒S battery, involved in electrode, electrolyte, membrane, binder, and current collector, has greatly promoted the performance of Li‒S batteries from the laboratory level to the approaching practical level. However, the safety concerns still deserve attention in the following application stage. This review focuses on the development of the electrolyte for Li‒S batteries from liquid state to solid state. Some problems and the corresponding solutions are emphasized, such as the soluble lithium polysulfides migration, ionic conductivity of electrolyte, the interface contact between electrolyte and electrode, and the reaction kinetics. Moreover, future perspectives of the safe and high-performance Li‒S batteries are also introduced.

Porosity parameters are one of the structural properties of the extracellular microenvironment that have been shown to have a great impact on the cellular phenotype and various biological activities such as diffusion of fluid, initial protein adsorption, permeability, cell penetration and migration, ECM deposition, angiogenesis, and rate and pattern of new tissue formation. The heterogeneity of the study protocols and research methodologies do not allow reliable meta-analysis for definite findings. As such, despite the huge available literature, no generally accepted consensus is defined for the porosity requirements of specific tissue engineering applications. However, based on the biomimetic approach, the biological substitutes should replicate the 3D local microenvironment of the recipient site with matching porosity parameters to best support local cells during tissue regeneration. Ideally, the porosity of biomaterials should mimic the porosity of the substituting natural tissue and match the clinical requirements. Careful analysis of the impact of architectures (i.e., porosity) on biophysical, biochemical, and biological behaviors will support designing smart biomaterials with customized architectural and functional properties that are patient and defect site-specific.

Herein, the rational design micromilieus involved silk fibroin (SF)-based materials have been used to encapsulate the osteoblasts, forming an extracellular coated shell on the cells, which exhibited the high potential to shift the regulation of osteoblasts to osteocytes by encapsulation cues. SF coating treated cells showed a change in cell morphology from osteoblasts-like to osteocytes-like shape compared with untreated ones. Moreover, the expression of alkaline phosphatase (ALP), collagen I (Col I) and osteocalcin (OCN) further indicated a potential approach for inducing osteoblasts regulation, which typically accelerates calcium deposition and cell calcification, presenting a key role for the SF encapsulation in controlling osteoblasts behavior. This discovery showed that SF-based cell encapsulation could be used for osteoblasts behavior regulation, which offers a great potential to modulate mammalian cells’ phenotype involving alternating surrounding cues.

Fast and broadband photoelectric detection is a key process to many photoelectronic applications, during which the semiconductor light absorber plays a critical role. In this report, we prepared Cu–In–Zn–S (CIZS) nanospheres with different compositions via a facile hydrothermal method. These nanospheres were ~200 nm in size and comprised of many small nanocrystals. A photodetector responded to the visible spectrum was demonstrated by spraying the solution processed nanospheres onto gold interdigital electrodes. The photoelectric characterization of these devices revealed that CIZS nanospheres with low molar ratio of n(Cu)/n(In) exhibited improved photoelectric response compared to those with high n(Cu)/n(In), which was attributed to the reduced defects. The relatively large switching ratio (I_on/I_off), fast response and wide spectral coverage of the CIZS-based photodetector render it a promising potential candidate for photoelectronic applications.

A reliable and efficient solution to the current energy crisis and its associated environmental issues is provided by fuel cells, metal–air batteries and overall water splitting. The heart reactions for these technologies are oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Different supporters such as graphene, carbon nanotube, and graphitic carbon nitride have been used to avoid agglomeration of active materials and provide maximum active surface for these reactions. Among all the supporters, boron nitride (BN) gains extensive research attention due to its analogue with graphene and excellent stability with good oxidation and chemical inertness. In this mini-review, the well-known strategies (exfoliation, annealing, and CVD) used in the synthesis of BN with different morphologies for HER, OER and ORR applications have been briefly debated and summarized. The comparative analysis determines that the performance and stability of state-of-the-art electrocatalysts can be further boosted if they are deposited on BN. It is revealed that BN-based catalysts for HER, OER and ORR are rarely studied yet especially with non-noble transition metals, and this research direction should be studied deeply in future for practical applications.

Flexible humidity sensors are widely used in many fields, such as environmental monitoring, agricultural soil moisture content determination, food quality monitoring and healthcare services. Therefore, it is essential to measure humidity accurately and reliably in different conditions. Flexible materials have been the focusing substrates of humidity sensors because of their rich surface chemical properties and structural designability. In addition, flexible materials have superior ductility for different conditions. In this review, we have summarized several sensing mechanisms, processing techniques, sensing layers and substrates for specific humidity sensing requirements. Aadditionally, we have sorted out some cases of flexible humidity sensors based on different functional materials. We hope this paper can contribute to the development of flexible humidity sensors in the future.

Early detection of cancer has multitude of advantages like early diagnosis, reduced risk, ease in the treatment and follow up of recurrence. New and developed techniques are always under research to control the spreading malignancy. Graphene is an emerging star in biomedical field as it exhibits exceptional thermal, electrical and optical properties. Here, we review application of graphene-based materials in developing biosensing devices for the detection of different cancer biomarkers at concentrations down to sub-toxic levels. Different analytical methodologies chosen for sensing have been undertaken and their performance and background have been discussed. The trend of use of these methodologies can also be perceived from the graphical data presented.

The fundamental relationship between microstructure, constituent, processing and performances of separating materials is really a vital issue. Traditional preparation methods for separation membranes are complex, time-consuming and easy to be fouled. Also, the durability of conventional coatings on membrane is poor. By combination of bioinspiration from mussel adhesive and fish scales’ underwater superoleophobicity, we propose a general route to prepare organic–inorganic hybrid coatings, while no complex apparatus is needed. Specifically, based on the biomimetic adhesion of polydopamine (PDA), we used it as a binder to adhere TiO₂ nanoparticles and built rough microstructure on fabric. In this way, we obtained TiO₂-PDA treated fabric with special wettability. These TiO₂-PDA treated samples owned superamphiphilicity in air, underwater superoleophobicity (underwater oil contact angles (OCAs)>150°), underoil superhydrophobicity (underoil water contact angles (WCAs)>150°), excellent multi-resistance; and can separate polar/nonpolar liquid mixture effectively. It also owned superaerophobicity underwater (underwater bubble contact angles (BCAs)>150°). The proposed TiO₂-PDA coatings are highly expected to be employed for real situation of water pollution remediation, self-cleaning, oil extraction and harsh chemical engineering issues.

A chronic wound in diabetic patients is a major public health concern with socioeconomic and clinical manifestations. The underlying medical condition of diabetic patients deteriorates the wound through physiological, metabolic, molecular, and cellular pathologies. Consequently, a wound enters a vicious pathological inflammatory cycle. Many therapeutic approaches are in practice to manage diabetic wounds hence ensuring the regeneration process. Polymer-based biomaterials have come up with high therapeutic promises. Many efforts have been devoted, over the years, to build an effective wound healing material using polymers. The electrospinning technique, although not new, has turned out to be one of the most effective strategies in building wound healing biomaterials due to the special structural advantages of electrospun nanofibers over the other formulations. In this review, careful integration of all electrospinning approaches has been presented which will not only give an insight into the current updates but also be helpful in the development of new therapeutic material considering pathophysiological conditions of a diabetic wound.

In this work, a high-performance fiber strain sensor is fabricated by constructing a double percolated structure, consisting of carbon nanotube (CNT)/thermoplastic polyurethane (TPU) continuous phase and styrene butadiene styrene (SBS) phase, incompatible with TPU (CNT/TPU@SBS). Compared with other similar fiber strain sensor systems without double percolated structure, the CNT/TPU@SBS sensor achieves a lower percolation threshold (0.38 wt.%) and higher electrical conductivity. The conductivity of 1%-CNT/TPU@SBS (4.12×10⁻³ S·m⁻¹) is two orders of magnitude higher than that of 1%-CNT/TPU (3.17×10⁻⁵ S·m⁻¹) at the same CNT loading of 1 wt.%. Due to double percolated structure, the 1%-CNT/TPU@SBS sensor exhibits a wide strain detection range (0.2%–100%) and an ultra-high sensitivity (maximum gauge factor (GF) is 32411 at 100% strain). Besides, the 1%-CNT/TPU@SBS sensor shows a high linearity (R² = 0.97) at 0%–20% strain, relatively fast response time (214 ms), and stability (500 loading/unloading cycles). The designed sensor can efficiently monitor physiological signals and movements and identify load distribution after being woven into a sensor array, showing broad application prospects in wearable electronics.

Size-constrained ultrathin BiOCl nanosheets@C composites were achieved by one-step hydrothermal route. It was found that the carbon coated on the surface of BiOCl nanosheets not only accelerated the separation of electrons and holes, but also restricted the outward growth of the BiOCl crystal structure to expose more active catalytic sites. In addition, the obtained composites have stable and close interface contact, beneficial for the structural stability of products as well as the rapid charge transfer. The average sheet thickness was in the range of 20–60 nm. Compared with the ability for pure BiOCl to degrade RhB, the degradation rate of the optimal composite can reach 100% within 15 min, while the corresponding photocurrent intensity could reach 5.6 μA·cm⁻², and its impedance value was also the smallest. The removal experiments of active substances showed that h⁺ and ∙O₂⁻ play important roles in the process of photocatalytic degradation. It can be expected that the resulted composites in this work can be used as potential materials for photocatalytic and photoelectrochemical applications.

Solar-driven evaporation has been considered as one of the potential methods for desalination and sewage treatment. However, optical concentrators and complex multi-component systems are essential in advanced technologies, resulting in low efficiency and high cost. Here, we synthesize a reduced graphene oxide-based porous calcium alginate (CA-rGO) hydrogel which exhibits good performance in light absorption. More than 90% of the light in the whole spectrum can be absorbed. Meanwhile, the water vapor escapes from the CA-rGO film extremely fast. The water evaporation rate is 1.47 kg·m⁻²·h⁻¹, corresponding to the efficiency 77% under only 1 kW·m⁻² irradiation. The high evaporation efficiency is attributed to the distinctive structure of the film, which contains inherent porous structure of hydrogel enabling rapid water transport throughout the film, and the concave water surfaces formed in the hydrophilic pores provide a large surface area for evaporation. Hydrophobic rGO divides the evaporation surface and provides a longer three-phase evaporation line. The test on multiple cyclic radiation shows that the material has good stability. The CA-rGO hydrogel may have promising application as a membrane for solar steam generation in desalination and sewage treatment.

Currently, δ-MnO₂ is one of the popularly studied cathode materials for aqueous zinc-ion batteries (ZIBs) but impeded by the sluggish kinetics of Zn²⁺ and the Mn cathode dissolution. Here, we report our discovery in the study of crystalline/amorphous MnO₂ (disordered MnO₂), prepared by a simple redox reaction in the order/disorder engineering. This disordered MnO₂ cathode material, having open framework with more active sites and more stable structure, shows improved electrochemical performance in 2 mol·L⁻¹ ZnSO₄/0.1 mol·L⁻¹ MnSO₄ aqueous electrolyte. It delivers an ultrahigh discharge specific capacity of 636 mA·h·g⁻¹ at 0.1 A·g⁻¹ and remains a large discharge capacity of 216 mA·h·g⁻¹ even at a high current density of 1 A·g⁻¹ after 400 cycles. Hence disordered MnO₂ could be a promising cathode material for aqueous ZIBs. The storage mechanism of the disordered MnO₂ electrode is also systematically investigated by structural and morphological examinations of ex situ, ultimately proving that the mechanism is the same as that of the δ-MnO₂ electrode. This work may pave the way for the possibility of using the order/disorder engineering to introduce novel properties in electrode materials for high-performance aqueous ZIBs.

Nanotoxicology has become the subject of intense research for more than two decades. Thousands of articles have been published but the space in understanding the nanotoxicity mechanism and the assessment is still unclear. Recent researches clearly show potential benefits of nanomaterials (NMs) in diagnostics and treatment, targeted drug delivery, and tissue engineering owing to their excellent physicochemical properties. However, these NMs display hazardous health effect then to the greater part of the materials because of small size, large surface area-to-volume ratio, quantum size effects, and environmental factors. Nowadays, a large number of NMs are used in industrial products including several medical applications, consumer, and healthcare products. However, they came into the environment without any safety test. The measurement of toxicity level has become important because of increasing toxic effects on living organisms. New realistic mechanism-based strategies are still needed to determine the toxic effects of NMs. For the assessment of NMs toxicity, reliable and standardized procedures are necessary. This review article provides systematic studies on toxicity of NMs involving manufacturing, environmental factors, eco-toxic and genotoxic effects, some parameters which have been ignored of NMs versus their biological counterparts, cell heterogeneity, and their current challenges and future perspectives.

A glucose-mediated drug delivery system would be highly satisfactory for diabetes diagnosis since it can intelligently release drug based on blood glucose levels. Herein, a glucose-responsive drug delivery system by integrating glucose-responsive poly(3-acrylamidophenylboronic acid) (PAPBA) functionalized hollow mesoporous silica nanoparticles (HMSNs) with transcutaneous microneedles (MNs) has been designed. The grafted PAPBA serves as gatekeeper to prevent drug release from HMSNs at normoglycemic levels. In contrast, faster drug release is detected at a typical hyperglycemic level, which is due to the change of hydrophilicity of PAPBA at high glucose concentration. After transdermal administration to diabetic rats, an effective hypoglycemic effect is achieved compared with that of subcutaneous injection. These observations indicate that the designed glucose-responsive drug delivery system has a potential application in diabetes treatment.

In the past few decades, many novel non-metal doped ZnO materials have developed hasty interest due to their adaptable properties such as low recombination rate and high activity under the solar light exposure. In this article, we compiled recent research advances in non-metal (S, N, C) doped ZnO, emphasizing on the related mechanism of catalysis and the effect of non-metals on structural, morphological, optical and photocatalytic characteristics of ZnO. This review will enhance the knowledge about the advancement in ZnO and will help in synthesizing new ZnO-based materials with modified structural and photocatalytic properties.