Taking inspiration from the human eye's information processing capabilities, the artificial optoelectronic neuronic device (AOEND) offers a promising approach to creating a bionic eye that performs real-time, low-power processing by integrating optical sensors, signal processing, and electronic neurons into a single device. Despite significant advancements, the current AOEND still faces challenges in terms of power consumption, flexibility, bio-compatibility, and, most importantly, achieving photo-sensitivity across the same broadband perceivable wavelength range (380nm to 740nm) as the human eye. In this study, we present a commercially ready, dual-gated thin-film-transistor (TFT)-based AOEND. Our device exhibits exceptional photo-response to specific wavelengths by utilizing an organic TIPS-pentacene material as the channel layer and intentionally tailoring its optical bandgap to approximately 1.6eV. Additionally, the device successfully replicates various photon-triggered synaptic characteristics and performs visual sensing, memory processing, and other functions with low power consumption. Our findings present a viable strategy for the development of future integrated sensing-memory-processing flexible devices for optoelectronic artificial retina perception applications.

Polymer dispersed liquid crystal (PDLC) films are emerging as a promising technological candidate for smart windows, whereby spatial patterning of the films to yield visually appealing designs, logos or images can significantly broaden their application scenarios. This paper presents UV grayscale printing generated patterned-film of the PDLCs for smart windows. An inexpensive color-patterned polyethylene terephthalate (PET) film (< 1 US dollar for A4 size) was used as the mask for UV printing. A systematic investigation into the impact of composite ratio, and curing temperature on the electro-optical performance of PDLCs gave the optimized processing parameters for UV grayscale printing. Low threshold and saturation voltages below 40 V with contrast ratio as high as 4405 can be achieved. Specifically, we show that varying UV intensity by using UV grayscale printing can tune threshold voltage, saturation voltage, and hysteresis, and affect contrast in turn, whereby the pattern printing was achieved. The prototypes support three voltage-controlled states including the ‘dark state’ to protect privacy, the ‘total transparent state’ to see-through, and the ‘pattern display state’ to show images and texts. Furthermore, the prototypes can achieve kinds of embedded images in the pattern display by controlling the applied voltages through designing the UV grayscale printing. The proposed UV grayscale printing generated patterned film is compatible with the existing LC production process and roll-to-roll production line, which enables the grayscale pattern design and benefits the mass production of spatial-patterned PDLC films for image-embedded smart windows.

Isoporous membranes with well-defined pore architectures offer a unique design approach to achieve a multi-scale porous network. For instance, isoporous membranes with progressively smaller pore sizes can be stacked to create a hierarchical pore network in which each length scale and the gradient of the pore network are deterministic by design. In this paper, we introduce a hierarchically-arranged multilayer isoporous air filter that comprises an ultrathin (thickness 95%) for ultrafine, most penetrating particle size (MPPS) while simultaneously reducing the pressure drop across the membrane (by ∼86%).

As a promising technology for material engineering, hybrid organic-inorganic (HOI) materials with a diversity of spatial hierarchical structures have become prospective candidates for cutting-edge applications. In this hot field of hybrid materials, considerable progress has been made in the manufacture of new systems toward large applicability. However, the complex synthesis pathways, stability and durability of such frameworks remain ongoing challenges facing us that seriously hinder the practical viability of this technology. Herein, an effective nest-like network is skillfully designed with both unique architectural design and outstanding structural activity of the self-assembled material resulting from a suitable band-gap configuration. Moreover, the present work put forward how the nest-like network would architecturally upgraded on the pre-existing Al2O3 porous film by plasma electrolytic oxidation (PEO) with the synergy of two organic molecules resulting in a tunable organic-inorganic hybrid material. This study inspired by the natural nest is realized to offer more adsorption and reaction sites in order to meet an excellent anti-corrosion performance, meanwhile achieving outstanding long-term stability. This strategy would open up a whole new possibility of the synergistic effect of two or more molecules for the fabrication of new hybrid materials not only endowed with excellent properties but also with facile synthetic route.

In this research, for the first time, sodium gluconate (SG) and zinc nitrate hexahydrate (Zn) were effectively inbuilt into NH2-MIL-125 (Ti) decorated graphene oxide (GO) nanolayers and then embedded into an epoxy coating (EP) to create an active (self-healing)/passive (barrier) anti-corrosion organic coating system. Various experiments were conducted to determine the characteristics of the synthesized nanomaterials. In addition, electrochemical impedance spectroscopy (EIS) techniques were used for the solution-phase study and exhibited 88% inhibitory efficacy for GO@MOF/SG-Zn. Moreover, the EIS test demonstrated that incorporating GO@MOF/SG-Zn into the EP enhanced its self-healing and barrier abilities. The total resistance (Rt) values of 636.14 KΩ.cm2 were obtained from the scratched EP-GO@MOF/SG-Zn sample, whereas the highest Rt values for the scratched EP and EP-GO were 91.25 and 76.78 KΩ.cm2, respectively. Also, after 84 days, the impedance value for the EP-GO@MOF/SG-Zn reduced to 10.51 Ω.cm2, which was a minor decrease among the examined samples.

Face masks have proven to be a useful protection from airborne viruses and bacteria, especially in the recent years pandemic outbreak when they effectively lowered the risk of infection from Coronavirus disease (COVID-19) or Omicron variants, being recognized as one of the main protective measures adopted by the World Health Organization (WHO). The need for improving the filtering efficiency performance to prevent penetration of fine particulate matter (PM), which can be potential bacteria or virus carriers, has led the research into developing new methods and techniques for face mask fabrication. In this perspective, Electrospinning has shown to be the most efficient technique to get either synthetic or natural polymers-based fibers with size down to the nanoscale providing remarkable performance in terms of both particle filtration and breathability. The aim of this Review is to give further insight into the implementation of electrospun nanofibers for the realization of the next generation of face masks, with functionalized membranes via addiction of active material to the polymer solutions that can give optimal features about antibacterial, antiviral, self-sterilization, and electrical energy storage capabilities. Furthermore, the recent advances regarding the use of renewable materials and green solvent strategies to improve the sustainability of electrospun membranes and to fabricate eco-friendly filters are here discussed, especially in view of the large-scale nanofiber production where traditional membrane manufacturing may result in a high environmental and health risk.

Photopolymer 3D printing techniques have a common limitation: the layers have to be deposited in a sequential order, which constrains multi-material fabrication to techniques where the vats have to be exchanged many times, in addition to repeating the cleaning step for each vat change. In this work, we present a technique that allows multi-material stereolithography by overcoming the layer-by-layer limitation, enabling one single immersion per resin. This is enabled by selective crosslinking of voxels at any depth and position inside the stereolithography (SLA) resin vat. The concept uses invisibility windows and upconversion to achieve selective volumetric crosslinking. This enables printing inside and through previously 3D printed parts. A photopolymer resin is developed, in which a visible light photoinitiator (fluorinated diphenyl titanocene) with a broad absorption and an optical absorber (naphthalimide class dye, maximum absorption at 445 nm) are carefully matched with the upconversion emissions of lanthanide-doped phosphors (both micron-sized phosphors and customized core/shell/shell nanoparticles). The lateral printing resolution of the formulation was found to be 134 ± 13 µm, which was improved to 103 ± 11 µm through the addition of light-absorbing dye. The vertical resolution was defined by the layer thickness achieved by lowering the build platform, which was set to 100 µm. The NIR light used for the excitation of upconversion phosphors enabled enhanced penetration depths of up to 5.8 cm, which allowed SLA printing of interwoven multi-color samples, multi-material rigid/flexible (acrylate/elastomer) samples and dielectric/metallic plated samples. This opens up a myriad of new possibilities, such as 3D printing objects inside cavities in a different material, restoration of broken objects and artefacts, 3D circuitry, insitu bioprinting, etc.

A new optimized photocatalyst for wastewater remediation at neutral pH has been developed and fully characterized. The catalyst features microparticles of SiO2 as a supporting substrate and a uniform shell of WO3 nanoparticles externally decorated with Fe3O4 nanocrystals. The photocatalytic activity of SiO2@WO3@Fe3O4 was evaluated and compared to its SiO2@WO3 counterpart on the photodegradation of methylene blue (MB) under visible light, with and without H2O2. Best results were obtained for SiO2@WO3@Fe3O4 in the presence of H2O2, whose potential for wastewater remediation was further evaluated on the photodegradation and mineralization of a contaminant of emerging concern such as diclofenac (DCF). Furthermore, a photocatalytic mechanism was proposed based on the performed electron paramagnetic resonance (EPR) experiments, which provided evidence for the intermediates generated in all the involved photocatalytic processes. Hence it was proven that .OH is the species responsible for the photocatalyzed oxidation of MB and DCF. The generation of .OH is boosted by a synergistic effect between Fe3O4 and WO3 in the presence of light and H2O2.

Hydrogel materials have biocompatibility, flexibility, transparency, self-healing ability, adhesion with various substrates, anti-freeze ability, and high-temperature resistance. However, the existing hydrogel devices cannot continue to operate in the case of damage, and they cannot work during the repair period, which brings great challenges and threats to life safety. Herein, we have designed a bio-inspired combinable low-power device by imitating the generation of nerve signals whose components can be disassembled and can continue to operate during the period of reconstruction. And the mechanism and determinants of the above phenomena are revealed. The results indicate that this device can establish some information interaction relationships with the body or its surroundings to reflect and identify certain changes, implying that it will possess promising potential in feedback systems, power transformers, intelligence systems, soft robotics, wearable devices, implanted electronics with flexible characteristics matching biological tissues, etc.

Novel hierarchical molybdenum-polydopamine nanocarriers (SMPDA) for hosting the inhibitors in the redesigned molybdenum-polydopamine-Zn2+ (SMPDA@Zn) form were utilized in the epoxy-based (EP) coating formulation to reinforce the barrier / self-healing functions. In the present study advanced FTIR, Raman, XRD, FESEM-EDS, MAP, TEM, BET, ICP-OES, EIS, PDP, OCP, salt spray, cathodic delamination, and pull-off appraisals techniques were employed to assess the influence of hierarchical nanocarriers in the solution and active / passive properties of epoxy coatings. The conspicuous impermeable hybrid films composed of Fe2+/3+-MoO42−, Fe2+/3+-polydopamine, Fe2+/3+-MoO42−-polydopamine and ZnO / Zn(OH)2 on active sites of mild steel in a saline solution comprising the SMPDA@Zn and SMPDA extract would supply %80 and %57 inhibition efficiency, respectively. Active corrosion protection in reference to Rtotal (Rct + Rf) 44463.1, 41879.3, and 9176.3 KΩ cm2 after 72 h immersion for composite and conventional EP coatings by plugging the polymeric film pores as well as healing the defects, intentionally created on the surface were enhanced interestingly up to 4.8 and 4.5 times. The superiority of the incorporated coatings was also obvious in the pull-off and cathodic disbanding tests so a delamination area reduction of %73 was recorded in the presence of the hierarchical nanocarriers. The present study illuminated new horizons in materials science and engineering on the potential usage of durable self-healing primer epoxy-based EPSZ and EPSM coatings in assorted industries like oil and gas pipelines, marine, and offshore infrastructure industries, refineries, petrochemical plants, non-renewable power plants, sheet metal working of shipbuilding, and subsea equipment.

The utilization of mesh materials to repair abdominal wall defects (AWDs) is one of the most common operations in the surgical field. However, the repair efficiency for biological meshes is restricted by poor neovascularization and limited abilities to prevent bacterial contamination. To address these issues, we design a new type of hierarchically hollow microcapsules (HHMs) by microfluidics. The hollow mesoporous silica nanoparticles filled in the aqueous core of HHMs form the first hollow structure, while the polymer shell of HHMs with tailorable thickness forms the second hollow structure. Under the precise emulsification process of microfluidics, HHMs have a high monodispersity with the coefficient of variation value about 1.9%. Taking advantages of the hierarchically hollow structure, the resultant microcapsules can store large amounts of angiogenic molecules, and deliver these cargos in a controlled manner. In vitro experiments find that the bioactivities of angiogenic molecules are well preserved after microencapsulation and promote the capillary tube formation of endothelial cells. In addition, silver nanoparticles (AgNPs) are incorporated into the HHMs shell to provide antibacterial properties for these microcapsules. When AgNPs concentration set to 0.4‰, the colony counting is reduced by 99.8% for Gram-negative bacteria and 94.8% for Gram-positive bacteria, while the proliferation activity of normal cells remains more than 80.0%. In vivo experiments find that HHMs can facilitate the new blood vessel formation, restrain the bacteria adhesion, and decrease the inflammatory response after implantation into a rat model with AWDs. These unique characteristics of HHMs thus create a healthy environment for biological meshes to induce the regeneration of AWDs, accompanied by collagen deposition and granulation formation. Collectively, the proposed HHMs are promising devices in the application of defected tissue repair.

Impurity doping has been widely exploited to give semiconductor nanocrystals (NCs) new optical, electrical, and magnetic properties. This review presents a critical overview of recent advances in the doping strategies, properties, and practical applications of transition metals, mainly focusing on Mn- and Cu-doped halide perovskites. We systematically summarized commonly used synthetic methods for Mn and Cu doping, doping-induced variations in structural and optoelectronic properties, and doping engineering in perovskites to optimize optoelectronic device performances, emphasizing the new properties arising from Mn and Cu ions dopants in halide perovskites. Furthermore, this review highlights the potential for using these Mn and Cu doped perovskite materials emphasizing different applications such as Light emitting diode (LEDs), solar cells, photocatalysis, and photodetectors. Key factors are presented, including device performance and architecture, the stabilization mechanism, and the reported performances. In short, this review will highlight recent trends in perovskite doping and will open new avenues of research and exploration in this burgeoning field.

The drug-resistant bacterial infection has seriously threatened human health and thus it is urgent to develop new and effective drugs to overcome the antibiotic resistance crisis. Herein, a near-infrared-II (NIR-II) region light-responsive Pd rough nanoshells on metal-organic framework (MOF) of UiO-66-NH2 (UiO-66-NH2@Pdshell) has been developed for the first time, which was further loaded with the photosensitizer IR780 to ultimately yield UiO-66-NH2@Pdshell-IR780 (UPI) as the core-shell theranostic nanoplatform. The Pd rough nanoshells demonstrate promising photothermal conversion efficiency, superoxide dismutase (SOD)-like activity, and light-enhanced catalase (CAT)-like activity. In the non-healing wound inflammatory microenvironment with overexpression of reactive oxygen species (ROS) caused by subcutaneous bacterial infection, Pd rough nanoshells in UPI transforms ROS, such as O2•−, into H2O2 and efficiently catalyzes the decomposition of the formed and endogenous H2O2 to produce O2. The O2 production process could be enhanced by NIR-II light to facilitate photodynamic efficacy of IR780 to prime rapid clearance of methicillin-resistant Staphylococcus aureus (MRSA) through biofilm inhibition, along with down-regulation of hypoxia inducible factor-1α (HIF-1α) and relief of inflammation, thus promote wound healing. Moreover, UPI exhibits negligible biotoxicity in vitro and in vivo. This work provides a method for preparing promising Pd-based nanomaterials toward subcutaneous infection treatment and wound healing.

Chronic wounds are known as one of the biggest health challenges, especially in the case of diabetes patients, which annually engages millions of patients, and its management imposes an exorbitant economic cost on societies worldwide. Therefore, there is an unmet need to find novel therapeutic methods with lower costs and higher efficiency. In recent years, a wide range of nanomaterials (NMs) has been utilized and shown promising results in treating different types of chronic wounds via playing a vital role as carriers for therapeutic agents or directly act as the therapeutic compound. NMs could affect different phases of the healing process, from hemostasis to remodeling, via influencing various intracellular factors. Towards this, the current review aims to provide the most recent research progress and prospect on the application of different NMs in chronic wound healing, particularly focusing on their effects on intracellular factors. The chronic wounds and intracellular pathways involved in this process are elaborated, and several NMs-based therapeutic agents used for chronic wound healing are described. The potential pitfalls and challenges of utilizing NMs in chronic wound healing are covered, and future perspectives toward more successful translational applications are presented.

This article presents a method for suppressing electrical crosstalk in a ferroelectric row-column (RC) actuator array. In high-density two-dimensional (2D) arrays, the RC addressing scheme has advantages over the conventional method of fully addressing the array, primarily due to its requirement for fewer interconnections to drive the elements. However, electrical crosstalk is an undesirable side effect that restricts the practical use of RC arrays for sensing and actuation. To mitigate this crosstalk between elements and allow activation of the target element, an addressing method using orthogonal biasing is investigated for the RC array. Due to the voltage-dependent polarization state of the ferroelectric film, each element exhibits bias-sensitive activity. Applying a coercive voltage bias to the electrically coupled elements via row electrodes to minimize the net polarization and piezoelectric activity reduces electrical crosstalk, leaving only acoustic crosstalk in the array. The method using coercive voltage bias reduces crosstalk between the elements by 6.25 dB compared to the conventional method. Furthermore, applying a negative bias of 7 V to the target element enhances its activity and increases its dynamic displacement by 33%, thus alleviating the crosstalk by 7.25 dB. The on-off switching characteristics of the biasing method are examined to investigate the feasibility of adopting such biasing in area scanning techniques for potential applications, such as ultrasonic imaging. By adjusting the magnitude of the DC bias, on-off switching operation is demonstrated at 5 kHz while achieving a 3 dB on-off ratio.

Energy remains to be a big challenge of the current century and therefore the issues related to it, including its production and storage, are among the important research topics today. Consequently, the search for new materials for energy storage devices is of fundamental importance. The fast charge/discharge, cycle stability, and considerable specific capacitance (Cs) of supercapacitors (SCs) has changed them to greatly interesting energy storage devices. To these advantages can be added higher power density and the reasonable cost of the electrode materials used in corresponding instruments. Metals tungstates are among the electrode materials with considerable cyclic performance, large rate capability, and Cs. Metal tungstates further reveal high crystal density, short radiation periods, outstanding optical character and resistance to radiation damage. For the first time, the methods of production of metal tungstates in recent years have been reviewed in this paper. In addition, the methods of strengthening the supercapacitive properties of metal tungstates have been reviewed.

In this study, open-cell porous bioceramics based on geopolymers were synthesized by the replica technique. The composition consisted of a mixture of metakaolin (MK) and hydroxyapatite (HA) that combined are suitable for application in bone tissue engineering. Metakaolin is a cheap natural aluminosilicate known for its mechanical properties, while hydroxyapatite stands out for its biocompatibility due to the chemical structure similar to the bone matrix. After undergoing heat treatment (HT), the geopolymer-hydroxyapatite (GMK-HA) synthesized materials, referred to as GMK-HA-HT, presented pores in the range from 1 to 5 mm. In the compressive strength tests, they exhibited values between 1.18 and 2.9 MPa. These ranges of values signify a proper balance between mechanical strength and porosity. X-ray diffraction analysis showed phosphate and/or calcium crystalline phases in all heat-treated samples, indicating HA's successful incorporation in the geopolymer structure. In vitro tests using human adipose-derived mesenchymal stem cells (ADSCs) were conducted to evaluate the biocompatibility of the synthesized materials. The extracts obtained from the GMK-HA-HT were found to be non-cytotoxic. ADSCs in contact with extracts have no morphological changes and when cultured on the GMK-HA-HT surface, the cells interacted with the scaffold and formed a monolayer. Here, for the first time, we provide insights into this new class of materials as a promising biomaterial candidate which could be associated with ADSCs to promote bone healing.

Multi-material metal/ceramic 3D structures comprising of metallic silver and ultra-low sintering temperature silver molybdenum oxide ceramics, have been additively manufactured and hybrid densified using microwave-assisted sintering for the first time. Optimum densification conditions at 440 °C / 1 h, resulted in relative permittivity, εr = 10.99 ± 0.04, dielectric losses, tanδ = 0.005 ± 0.001 and microwave quality factor, Q × f = 2597 ± 540 GHz. Applying 2 kW microwave energy at 2.45 GHz for 60 min, was proven sufficient, to densify the metallic Ag infilling electrodes, without causing any macroscopic defects. A fully functional multi-layered antenna structure with a metamaterial artificial magnetic conductor was designed, dual-printed and densified, to showcase the potential of combining multi-material additive manufacturing with microwave-assisted sintering.

Existing commercial material extrusion (ME) polymer filaments frequently fail to meet the requirements of actual workpieces and often need improvement through modification. However, traditional modification methods are time-consuming and expensive. Here, we develop a 3D printer capable of blending three polymers and programming the component ratios, which can speed up such a modification process. Additionally, workpieces with varying properties can be quickly produced (just like mixing colors according to the three primary colors) with the guidance of machine learning algorithms. As a demonstration, we used polylactic acid (PLA), thermoplastic polyurethane (TPU), and polyethylene terephthalate glycol (PETG) three commercial filaments as base materials to printout different objects. The tensile strength, tensile modulus, flexural strength, flexural modulus, and hardness of 67 groups of different PLA/TPU/PETG blend components were tested. Based on these data, artificial neural network (ANN) optimization algorithms were used to discover the relationship between the components and properties. The results show that using ANN to predict the mechanical properties of blended polymers can effectively accelerate the development of materials. Materials with tunable properties and complex structures can be manufactured from simple raw materials through 3D printing quickly.

COPrOx reaction is one of the particularly appealing and cost-effective solutions for the selective oxidation of CO in hydrogen-rich gas streams to meet the stringent requirement of the current electrocatalysts employed in low-temperature fuel cells. Herein, we synthesized ultrasmall Au clusters supported on ceria by one-step solvent-free mechanochemical method. These catalysts exhibited higher activity for COPrOx and CO oxidation compared to the sample prepared by conventional incipient wetness impregnation. The unique Au-Ce interaction caused by impact and friction between the ball, vessel, and powders, greatly promotes the generation of positive charged Auδ+ active sites and, at the same time, the reducibility of the catalyst. Interestingly, an aging treatment of the ball-milled samples resulted in a significant superior performance of the catalytic activity. This enhancement has been attributed to a change in the oxidation state of Au between the fresh and the aged catalysts prepared by ball milling.