Material For Fabrication Research Articles

Improved performance and stability in CH3NH3PbI3/Si heterojunction photodetectors realized by ZIF-67 additive assisted Co ion doping

Lead halide perovskites have been regarded as promising materials for fabrication of high-performance photodetectors (PDs). However, spin-coated perovskite thin films generally have suffered from high-density grain boundaries and defect states, which severely deteriorated the performance and stability of resulting PDs. Fortunately, the above issues can be effectively solved via additive assisted metal ions doping. In this work, Co-based zeolite imidazole framework (ZIF-67) additive assisted Co ion doping has been proposed to prepare high-quality perovskite CH3NH3PbI3 (MAPbI3) thin films. Morphological, structural, optical, and electrical studies have shown that Co ion doping decreased grain boundaries as well as suppressed defect states, which greatly enhanced the performance and stability of MAPbI3/Si heterojunction PDs, including reducing dark current, increasing photocurrent, and increasing response speed. Finally, the mechanisms of suppression of defect states benefiting from Co ion doping were discussed based on density functional theory calculations. The results provided in this work will pave the way for development of high-performance and stable MAPbI3 PDs in the future.

Chitosan-based mixed matrix composite membranes for CO2/CH4 mixed gas separation. Experimental characterization and performance validation

Membrane technology is acknowledged as one of the most efficient for biogas upgrading, separating simultaneously CH4 and CO2 in the retentate and permeate streams, respectively. The sustainability would still be improved by using renewable and environmentally friendly materials for membrane fabrication. Specifically, this study is focused on laboratory-scale mixed gas separation tests of composite membranes prepared from chitosan (CS), a hydrophilic, biodegradable and biocompatible polymer from abundant natural resources, with good adhesive and film forming properties and high affinity for CO2 due to the primary amine and hydroxyl groups functionalities in CS. To improve mechanical resistance and CO2/CH4 separation, CS was hybridized by a 5 wt% loading of non-toxic ionic [emim][acetate] liquid (IL), and variable loadings of compatible inorganic fillers, such as 3D zeolite 4A and NaETS-10, and layered AM-4 titanosilicate. The CS-based mixed matrix layer was coated on porous polyether sulfone (PES) support. The CO2 permeance and CO2/CH4 separation were measured at different feed concentrations to evaluate the membranes performance in the treatment of different streams. This separation behavior was explained by the wet thickness, water uptake, morphology and ionic resistance of the composite membrane. As such, the 5 wt% Zeolite 4A and NaETS-10-filled ILCS/PES membranes provided a good dispersion in the ILCS matrix and the mixed matrix layer a good adhesion with the porous PES support, leading to high CO2 permeances and separation factors up to 30, whereas the more hydrophilic lamellar AM-4 titanosilicate-filled ILCS layer showed cluster agglomeration in the matrix and a faster detachment of the coated layer from the PES substrate. With increasing filler loading, an increase of the permeance of both CO2 and CH4 gas components was, although selectivity decreased upon increasing AM-4 filler loading. The CO2/CH4 mixed gas separation performance was validated by a custom-built model for a wide range of feed composition, to cover such processes as natural gas sweetening, biogas upgrading and enhanced oil recovery with acceptable relative error below 10% (absolute value), except for the AM-4 titanosilicate-filled ILCS membranes, showing morphological fabrication defects.

Robust and fouling-resistant ultrathin membranes for water purification tailored via semi-dissolved electrospun nanofibers

Energy-efficient membranes with high mechanical strength and fouling resistance is highly required in the current membrane industry. In this research, a novel type of water purification membrane was fabricated using a nylon 6 nanofiber membrane as a base polymer and further mechanical processing. The electrospun nylon 6 membrane was first semi-dissolved by spraying diluted formic acid solvent, then re-casted by thermal rolling, and a very-tight ultrafiltration membrane named SP6 was obtained. Fabricated SP6 had an ultrathin thickness of 9 μm and ultimately high mechanical strength (53 MPa). Owing to the enhanced hydrophilicity and ultra-low thickness, a 59 ± 7 LMH water flux was observed for SP6. Furthermore, SP6 showed 98 ± 0.85% humic acid (H.A) and 92.13 ± 0.46% organic dye rejection. When an organic fouling study was conducted (8 h H.A. fouling tests with 30 min DI water filtration/flushing in between), SP6 had only a 20% drop, which also recovered up to 90% after 30 min of DI water filtration. After the fouling test was completed, significantly less foulant (2817 ± 1503 μm3) was observed on the surface of SP6 (on the 500*500 μm2 surface area), in line with the trend for the flux recovery. Therefore, this novel approach utilizing semi-dissolved nanofibers as fabrication material could represent a path for fabricating membranes with great longevity for practical applications.

Thermal performance of gasifier cooking stoves: A systematic literature review.

A systematic literature review was conducted to summarize the overall thermal performance of different gasified cooking stoves from the available literature. For this purpose, availablestudies from the last 14 years (2008 to 2022)were searched using different search strings. After screening, a total of 28 articles were selected for this literature review.Scopus, Google Scholar, and Web of Science databases were used as search strings by applying "Gasifier cooking stove" AND "producer gas cooking stove" AND "thermal performance" keywords. This review uncovers different gasified cooking stoves, cooking fuels, and fabrication materials besides overall thermal performances. The result shows that the overall thermal performance of different gasified cooking stoves was 5.88% to 91% depending on the design and burning fuels. The premixed producer gas burner with a swirl vane stove provided the highest overall thermal performance range, which was 84% to 91%, and the updraft gasified stove provided the lowest performance, which was 5.88% to 8.79%. The result also demonstrates that the wood pellets cooking fuel provided the highest thermal performance and corn straw briquette fuel provided the lowest for gasified cooking stoves. The overall thermal performance of wood pellets was 38.5% and corn straw briquette was 10.86%.

MATERIALS AND METHODS FOR CERAMIC MEMBRANE SYNTHESIS. SHORT REVIEW

This article briefly overviews the main types of raw materials used to synthesise ceramic membranes. Traditional materials such as aluminium oxide, silicon dioxide, titanium dioxide, zirconium dioxide, zeolites, and cost-effective materials like various clays and industrial waste are highlighted. Modern methods for producing high-performance ceramic membranes are discussed, including slip casting, tape casting, pressing, extrusion, solid state method etc. The general scheme for preparing a selective layer on a ceramic membrane using various methods for synthesising it is also examined. Furthermore, the cost of commercial ceramic membranes and influencing factors are analysed. Based on contemporary literature, ceramic membranes exhibit distinct advantages over polymer membranes with their potential for application under high temperature, high pressure, and aggressive environments. Additionally, their energy efficiency, compactness, and versatility make them a viable alternative for water purification, replacing more expensive methods like coagulation and adsorption. Ceramic membranes have become a competitive alternative to polymer membranes, showcasing unique material properties and excellent characteristics. Using cost-effective materials for ceramic membrane fabrication allows for utilisation in economically sensitive sectors. Such membranes demonstrate excellent mechanical properties and high permeability, while inexpensive materials can reduce costs. Current scientific research and developments focus on utilising various clays and waste materials to produce ceramic membranes, aiming to create new generations of ceramic membranes for environmentally friendly applications.

Tailoring hierarchical BiVO4 sub-micron particles for enhanced cyclability in asymmetric supercapacitor

This work demonstrates the feasibility of sub-micron size metal oxides as a sustainable charge storage material in supercapacitors fabrication and addressing the cycle instability issues of pseudocapacitors. The sub-micron bismuth vanadate (BiVO4) particles were synthesized by two different routes, co-precipitation (BVO-N) and sonochemical (BVO-S) methods. The morphological investigation of BVO-S showed hierarchical microspheres with diameter ranges of 1–6 μm, which is more prominent in size compared to BVO-N particles (100 nm- 1-μm in diameter). The nitric acid plays a crucial role in stabilizing the BiVO4 particles in the co-precipitation process, whereas ultrasonic waves predominantly control the spherical particle formation in the sonochemical route. The electrochemical performance of BVO-N and BVO-S was tested in a potassium hydroxide (KOH) electrolyte. The charge and discharge cycle experiments showed BVO-S microspheres are more highly stable than that BVO-N. The BVO-N starts to degrade with its initial capacitance beyond 1000 cycles. The poor stability of BVO-N may be due to the breakdown of surface-adsorbed charged ionic species. As a result, BVO-S performs with a higher specific capacitance value of 214 F/g compared to BVO-N (124 F/g). Trasatti analysis revealed a balanced, synergistic behaviour of pseudocapacitance (61 %) and electric double layer capacitance (39 %) at the BVO-S is responsible for their high specific capacitance compared to BVO-N. The BVO-S has low intrinsic resistance due to the highly denser micro-spherical structure, allowing electrolyte ions to access the inner and outer surfaces of the BVO-S. Interestingly, charge transfer resistance was decreased after the cyclic stability test due to electrochemical activation and facilitates fast ion transport increasing the surface contact area of active material at the electrode-electrolyte interface. We fabricate the asymmetric cell with BVO-S microspheres (anode), activated carbon particles (cathode) and Poly (ethylene oxide) (PEO) /Polyethene glycol dimethyl ether (PEGDME)/KOH gel-based electrolyte. This asymmetric supercapacitor performs with a specific capacitance value of 153 F/g at 0.3 A/g under the cell voltage of 1.2 V. Also, it delivers 30.6 Whkg−1 of energy density and 1983 W kg−1 of power density. The cyclic stability of 98 % over 5000 cycles was achieved in this configuration. This performance is appreciable compared to the previous work on BiVO4-based asymmetry supercapacitors, particularly a capacitance retention (%) and potential window. Overall, an acid-free sonochemical processing route reported in this work is highly environmentally friendly. Likewise, the sub-micron metal oxide particle significantly improves their electrochemical stability without the coalesced together with any carbonaceous material. It can be transferred to synthesizing a broader choice of metal oxide based for enhanced cyclability with effective utilization of their charge storage behaviour that will perform high-power storage, which powers short-distance electric transportation.

Influence of Natural Fiber Derived from Agricultural Waste on Durability and Micro-Morphological Analysis of High-Strength Concrete

This research focuses on the investigation of durability behavior and microstructural analysis for M70 grade of high-strength concrete (HSC) with the influence of alccofine, banana fiber (BF), and coir fiber (CF). In this investigation, cement was partly supplanted by 15% of alccofine content in weight. Two types of natural fibers, banana and coir fibers, were selected and added in concrete at 0.5%, 1%, 1.5%, and 2% by volume. Durability characteristics, such as long-term compressive performance, rapid chloride penetration, sorptivity, water absorption, volume of permeable voids, and acid attack resistance are investigated elaborately and correlate with conventional HSC. Results showed that the incorporation of banana and coir fibers with alccofine in HSC exhibited good durability performance as correlated with conventional HSC. At 180 days of curing, incorporating 1% of banana fiber increased the durability performance compared to reference HSC. Nonetheless, the high-fiber percentage of HSC has a slight reduction in durability characteristics. Among the two types of fibers, the banana fiber showed the most significant improvement in the durability properties of HSC. The influence of natural fiber on the microstructural characteristics of HSC was evaluated using scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) to substantiate the experimental findings. In contrast, using additional supplementary cementitious materials (SCMs) in HSC fabrication significantly reduces cement usage and carbon emissions.

Bioinspired Macroporous Materials of MXene Nanosheets: Ice-Templated Assembly and Multifunctional Applications.

Biological macroporous materials, such as stems of the plants and bone of the animals, possess outstanding properties for powerful guarantee of creatures' survival through the well-aligned architecture constructed from limited components. Transition metal carbides or nitrides (MXenes), as novel 2D assemblies, have attracted numerous attentions in various applications due to their unique properties. Therefore, mimicking the bioinspired architecture with MXenes will boost the development of human-made materials with unparalleled properties. Freeze casting has been widely applied to fabricate bioinspired MXene-based materials and achieve the assembly of MXene nanosheets into 3D forms. This process solves the inherent restacking problems of MXenes, simultaneously preserving the unique properties of MXenes with a physical process. Here, the ice-templated assembly of MXene in terms of the freezing processes and their potential mechanisms is summarized. In addition, applications of MXene-based materials in electromagnetic interference shielding and absorption, energy storage and conversion, as well as piezoresistive pressure sensors are also reviewed. Finally, the current challenges and bottlenecks of ice-templated assembly of MXene are further discussed to guide the development of bioinspired MXene-based materials.

Recent Advance in Low‐Dielectric‐Constant Organosilicon Polymers

Comprehensive SummaryLow dielectric (low‐k) organosilicon polymers have received extensive interests from industry and academia due to good electrical insulation, high temperature resistance, flame retardancy and hydrophobicity. These attractive properties enable them to be utilized as low‐k materials in fabrication of electronic devices in high‐frequency communication technology. This review summarizes recent progress in developing low‐k organosilicon polymers, including the synthetic methods and properties of different organosilicon polymers classified according to the chemical structures. It may provide some inspiration to design new low‐k organosilicon polymers for application in the future.

Samarium ion-doped calcium silicate: A promising material for fabrication of light emitting diodes

In this work, calcium silicate nanophosphors (CaSiO3) doped with Sm[Formula: see text] ions were prepared at [Formula: see text]C by a simple solution combustion synthesis technique. The particle size, functional groups and morphology of the prepared phosphors were identified by X-Ray diffraction (XRD), Fourier transform infrared (FTIR), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) techniques. The monoclinic phase of the nanophosphors was confirmed by X-ray diffraction studies. The effective excitation of the nanophosphors near the UV region and their yellow emission were confirmed by photoluminescence studies.

Fiber reinforced hydrated networks recapitulate the poroelastic mechanics of articular cartilage

The role of poroelasticity on the functional performance of articular cartilage has been established in the scientific literature since the 1960s. Despite the extensive knowledge on this topic there remain few attempts to design for poroelasticity and to our knowledge no demonstration of an engineered poroelastic material that approaches the physiological performance. In this paper, we report on the development of an engineered material that begins to approach physiological poroelasticity. We quantify poroelasticity using the fluid load fraction, apply mixture theory to model the material system, and determine cytocompatibility using primary human mesenchymal stem cells. The design approach is based on a fiber reinforced hydrated network and uses routine fabrication methods (electrohydrodynamic deposition) and materials (poly[ɛ-caprolactone] and gelatin) to develop the engineered poroelastic material. This composite material achieved a mean peak fluid load fraction of 68%, displayed consistency with mixture theory, and demonstrated cytocompatibility. This work creates a foundation for designing poroelastic cartilage implants and developing scaffold systems to study chondrocyte mechanobiology and tissue engineering. Statement of significancePoroelasticity drives the functional mechanics of articular cartilage (load bearing and lubrication). In this work we develop the design rationale and approach to produce a poroelastic material, known as a fiber reinforced hydrated network (FiHy™), that begins to approach the native performance of articular cartilage. This is the first engineered material system capable of exceeding isotropic linear poroelastic theory. The framework developed here enables fundamental studies of poroelasticity and the development of translational materials for cartilage repair.

Concha-Type Microtia: New Surgical Incision.

Reconstruction of auricles for conchal-type microtia is challenging but rewarding. Many plastic surgeons consider autogenous rib cartilage as the standard material for framework fabrication. A healthy, scar-free skin envelope and a defined cartilaginous framework are also critical to successful ear reconstruction. The aim of this study was to improve the outcome of the reconstruction and minimize complications by proposing a new surgical incision. Thirty-three patients who underwent auricular reconstruction of concha-type microtia of various etiologies with the new skin flap incision between 2017 and 2022 were included in the study. Patients' clinical data, detailed surgical techniques, and postoperative care were recorded. Thirty-three patients (21 male, 12 female) were enrolled in the study. The mean age of the patients was 21.51 years at the time of reconstruction. The microtia was on the right side in 17 cases, on the left side in 12 cases, and 4 cases were bilateral; 12 cases were traumatic amputations of the helical component of the auricle, 11 cases were deformities after a burn, and 10 cases were congenital. The mean follow-up time was 17.43 months. A good initial projection without obvious scarring on the anterior surface of the auricle was achieved, with an overall complication rate of 5.42%. The surgical incision recommended in the study improves the final aesthetic result of the technique without any additional surgical risk.

Shockproof Deformable Infrared Radiation Sensors Based on a Polymeric Rubber and Organic Semiconductor H2Pc-CNT Composite.

Polymeric rubber and organic semiconductor H2Pc-CNT-composite-based surface- and sandwich-type shockproof deformable infrared radiation (IR) sensors were fabricated using a rubbing-in technique. CNT and CNT-H2Pc (30:70 wt.%) composite layers were deposited on a polymeric rubber substrate as electrodes and active layers, respectively. Under the effect of IR irradiation (0 to 3700 W/m2), the resistance and the impedance of the surface-type sensors decreased up to 1.49 and 1.36 times, respectively. In the same conditions, the resistance and the impedance of the sandwich-type sensors decreased up to 1.46 and 1.35 times, respectively. The temperature coefficients of resistance (TCR) of the surface- and sandwich-type sensors are 1.2 and 1.1, respectively. The novel ratio of the H2Pc-CNT composite ingredients and comparably high value of the TCR make the devices attractive for bolometric applications meant to measure the intensity of infrared radiation. Moreover, given their easy fabrication and low-cost materials, the fabricated devices have great potential for commercialization.

Fabrication Strategies for Engineered Thin Membranous Tissues.

Thin membranous tissues (TMTs) are anatomical structures consisting of multiple stratified cell layers, each less than 100 μm in thickness. While these tissues are small in scale, they play critical roles in normal tissue function and healing. Examples of TMTs include the tympanic membrane, cornea, periosteum, and epidermis. Damage to these structures can be caused by trauma or congenital disabilities, resulting in hearing loss, blindness, dysfunctional bone development, and impaired wound repair, respectively. While autologous and allogeneic tissue sources for these membranes exist, they are significantly limited by availability and patient complications. Tissue engineering has therefore become a popular strategy for TMT replacement. However, due to their complex microscale architecture, TMTs are often difficult to replicate in a biomimetic manner. The critical challenge in TMT fabrication is balancing fine resolution with the ability to mimic complex target tissue anatomy. This Review reports existing TMT fabrication strategies, their resolution and material capabilities, cell and tissue response, and the advantages and disadvantages of each technique.

Rapid diagnosis of COVID-19 using disposal paper capacitive sensor

Accurate and rapid detection and isolation become indispensable to restrict the spread of COVID-19. Since the start of COVID-19 pandemic in December 2019, many indisposal diagnostic tools are being developed incessantly. Out of all presently used tools, the gold standard rRT- PCR tool having very high sensitivity and specificity is a time consuming complicated molecular technique having requirements of special expensive equipment. Here, the main focus of this work is to develop rapid disposal paper capacitance sensor having simple and easy detection. We discovered a strong interaction between limonin and Spike-glycoprotein of SARS-COV-2 in comparison to its interaction with other similar viruses such as HCOV-OC43, HCOV-NL63, HCOV-HKU1, Influenza B and A viruses. The antibody free capacitive sensor having comb electrode structure was fabricated on whatman paper with drop coating of limonin (extracted using green method from pomelo seeds) and calibrated with known swab samples. The Blind test with unknown swab samples shows high sensitivity of 91.5% and high specificity of 88.37%. Requiring low sample volume and detection time and using biodegradable materials in the sensor fabrication assure the potential application as a point of care disposal diagnostic tool.

Copper Phosphide Nanowires as High-Performance Catalysts for Urea-Assisted Hydrogen Evolution in Alkaline Medium.

Water electrolysis represented a promising avenue for the large-scale production of high-purity hydrogen. However, the high overpotential and sluggish reaction rates associated with the anodic oxygen evolution reaction (OER) posed significant obstacles to efficient water splitting. To tackle these challenges, the urea oxidation reaction (UOR) emerged as a more favorable thermodynamic alternative to OER, offering both the energy-efficient hydrogen evolution reaction (HER) and the potential for the treating of urea-rich wastewater. In this work, a two-step methodology comprising nanowire growth and phosphating treatment was employed to fabricate Cu3P nanowires on Cu foam (Cu3P-NW/CF) catalysts. These novel catalytic architectures exhibited notable efficiencies in facilitating both the UOR and HER in alkaline solutions. Specifically, within urea-containing electrolytes, the UOR manifested desirable operational potentials of 1.43 V and 1.65 V versus the reversible hydrogen electrode (vs. RHE) to reach the current densities of 10 and 100 mA cm-2, respectively. Concurrently, the catalyst displayed a meager overpotential of 60 mV for the HER at a current density of 10 mA cm-2. Remarkably, the two-electrode urea electrolysis system, exploiting the designed catalyst as both the cathode and anode, demonstrated an outstanding performance, attaining a low cell voltage of 1.79 V to achieve a current density of 100 mA cm-2. Importantly, this voltage is preferable to the conventional water electrolysis threshold in the absence of urea molecules. Moreover, our study shed light on the potential of innovative Cu-based materials for the scalable fabrication of electrocatalysts, energy-efficient hydrogen generation, and the treatment of urea-rich wastewater.

3D printing methods and materials for sensor fabrication

Recent advancement in the 3D printing process also brings interest in improving the sensor fabrication process. There is a huge demand for sensors in various applications. Industry 4.0 revolution’s main aim is to bring advancement and improve productivity. In this paper, we have reviewed recent work in 3D printed sensors, an overview of the sensor, traditional fabrication techniques and 3D printing techniques. This paper focused on 3D-printing engineering application sensors. For a better understanding of 3D printing technology, its classification is also discussed in detail so that we can understand commonly used 3D printing techniques. For studying sensor fabrication commonly used materials are also discussed and with a lot of drawbacks that need to be improved in sensor fabrication.

Bimetallic nickel-cobalt nanospheres electrodeposited on nickel foam as a battery-type electrode material for fabrication of asymmetric supercapacitors

The development of electrode materials with nanostructures is of great importance in the field of supercapacitors. In the present research, the direct simultaneous deposition of Ni-Co nanosphere (Ni-Co NS) on nickel foam as a substrate has been performed by facile one-step electrodeposition method without any template to provide excellent electrical conductivity and efficiency of electrode materials. The SEM images of Ni-Co NS electrode showed a nanosphere shape. The electrochemical performance of the electrodeposited nanosphere has been investigated by cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy in 3 M KOH aqueous electrolyte. The Ni-Co NS electrode showed a good specific capacity of 564.6 C g−1 at 2 A g−1 with rate capability of 70% in the current density range of 2–20 A g−1, reasonable cyclic stability of 86% after 5000 cycles at the scan rate of 70 mV s−1, low internal resistance, and high surface area of the nanospheres. Interestingly, an asymmetric supercapacitor fabricated using Ni-Co NS and activated carbon as the positive and negative electrodes, respectively, operating at the potential window of 1.5 V delivered high energy and power densities of 34.5 Wh kg−1 and 683 W kg−1, respectively.

Low-melting-point alloys integrated extrusion additive manufacturing

Additive manufacturing has developed significantly. In contrast to established fabricated materials, low-melting-point alloys (LMPAs) are increasingly attractive because they have favorable electrical/thermal conductivities and mechanical strengths. However, LMPA additive manufacturing is still in its infancy. We report a novel strategy for fabricating the complex and/or multifunctional components of LMPAs by extrusion additive manufacturing with two nozzles (for extruding the polymer and for extruding the LMPA). The proposed strategy was used to successfully fabricate complex LMPA components for the first time. We fabricated LMPA/polymer composite parts with improved mechanical properties, and implemented the integrated manufacturing of circuits and 3D products. The strategy will enable the use of LMPAs in applications such as smart structures, electromagnetic shielding, biomedicine, thermal management, energy harvesting, and advanced electronics.

Japanese earnings slumped in fiscal 2022

Japanese chemical companies ground through a tough fiscal year 2022. For the period, which ended March 31, sales rose for nearly every major firm, but earnings were down almost across the board as companies grappled with sluggish economic conditions and rising costs for energy and raw materials . Sumitomo Chemical saw its profits decline over 95%, even as sales rose nearly 5%. In its earnings statement, the company blames a poor global economy compared with 2021: “Although the impact of the COVID-19 pandemic eased, economic growth was held back by such factors as global monetary tightening to control inflation and a delay in the recovery of China’s economy.” Sales in Japan benefited from a rise in consumer spending, Sumitomo says, but high raw-material prices weighed on earnings. The company saw strength in materials for semiconductor fabrication but weakness in those for displays. Mitsubishi Chemical Group says the global economy “continued