Nanotubes Research Articles

Band gap, ferromagnetic resonance and strong microwave absorption of BaFe12-2xZnxSnxO19 compounds and enhanced dielectric loss in BaFe12-2xZnxSnxO19/carbon nano tube composites

The forbidden bandgap energy, magnetic properties, natural ferromagnetic resonance and microwave absorption are studied on the Zn2+ and Sn4+ doped BaFe12-2xZnxSnxO19. The forbidden band gap of BaFe12-2xZnxSnxO19 increases with the increasing doping content x from 1.80 eV up to 1.97 eV. The coercive field, the anisotropy field and the magnetocrystalline constant of BaFe12-2xZnxSnxO19 decreases with the increasing doping. The natural ferromagnetic resonance is observed. The high permeability, accompanied with the ferromagnetic resonance, enables strong microwave absorption. BaFe10.4Zn0.8Sn0.8O19 has a wide effective microwave absorption bandwidth (RL≤-10dB) of 6 GHz with the material thickness below 2.5 mm in 11.4–17.4 GHz. The dielectric loss has little contribution to the excellent microwave absorption of BaFe12-2xZnxSnxO19. The BaFe12-2xZnxSnxO19/carbon nanotube (CNT) composites significantly increase the permittivity. The high dielectric loss and the high magnetic loss further improve the microwave absorption. With a very thin thickness of 1.8 mm, BaFe10.4Zn0.8Sn0.8O19/CNT has a bandwidth of 7.1 + GHz of 10.9–––18 + GHz. With the material thickness thinner than 3 mm, BaFe12-2xZnxSnxO19/CNT composites have very broad effective microwave absorption bandwidth of 11.4+, 10.7 and 10.7 GHz, with x = 0.6, 0.8 and 1.0, respectively. It illustrates that both BaFe10.4Zn0.8Sn0.8O19 and BaFe12-2xZnxSnxO19/CNT composites are very promising microwave absorbers.

3D-printable construction and demolition waste-based geopolymer: Investigating the effects of additives on engineering properties

This paper focuses on the investigating the effects of various additives on the engineering properties of construction and demolition waste (CDW)-based geopolymer mortars. In this study, low-activity CDW-based precursors, specifically brick waste (BW) and concrete waste (CW), were employed. Additionally, industrial waste-based precursors such as slag (S) and silica fume (SF) were utilized to enhance the overall composition. To facilitate activation, a 5 M solution of NaOH was used. To address the efflorescence issue prevalent in geopolymer mixtures and to eliminate potential cracks that may arise due to the dimensional stability problem of 3D-printed CDW-based geopolymer, various kind of additives including calcite, polypropylene fiber, nano SiO2, Al2O3, and TiO2, carbon nano tubes (CNTs), graphene nanoplatelet (GNP), methyl cellulose (MC), Na2SiO3, calcium oxide (CaO), calcium aluminate cement (CAC), and Ca(OH)2 were incorporated into the matrix. The research utilized a comprehensive testing methodology, allowing for a detailed exploration of various properties and the performance of the geopolymer mixtures. The results indicated that nano SiO2 and Al2O3, Na2SiO3, BW, and CAC were recognized for their positive impact on improving the mechanical properties of the geopolymer. Notably, the geopolymer exhibited an impressive compressive strength of 29.8 MPa and a flexural strength of 5.4 MPa following a 28-day ambient curing (23 ± 2 °C and 50 ± 5% relative humidity). Furthermore, the inclusion of nano SiO2 and Al2O3, GNP, MC, Na2SiO3, CaO, CAC, and Ca(OH)2 proved effective in preventing efflorescence, while MC, Na2SiO3, CaO, CAC, and Ca(OH)2 successfully mitigated cracks formation. The results also demonstrated that the CDW-based geopolymer mixture is suitable for 3D printing, displaying satisfactory buildability, shape retention, and extrudability. A thorough testing approach highlighted the effectiveness of additives in shaping the properties of CDW-based geopolymer, positioning them as promising for improvement and addressing challenges.

Review of: "Nano tubes of carbon C70 as a strong oxidizing insulation layers for low power energy organic act."

Review of: "Nano tubes of carbon C70 as a strong oxidizing insulation layers for low power energy organic act."

Abstract 5980: Cancer therapeutic and prevention strategy targeting mutated mitochondria DNA

Abstract As the energy factory for the cell, the mitochondrion, through its role of ATP production by oxidative phosphorylation, can be regarded as the guardian of well regulated cellular metabolism; the integrity of mitochondrial functions, however, is particularly vulnerable in cancer due to the lack of superstructures such as histone and lamina folds to protect the mitochondrial genome from unintended exposure, which consequently elevates risks of mutation. In cancer, mechanisms responsible for enforcing quality control surveillance for identifying and eliminating defective mitochondria are often poorly regulated, and certain uneliminated mitochondrial DNA (mtDNA) mutations and polymorphisms can be advantageous for the proliferation, progression, and metastasis of tumor cells and disseminated into microenvironment cells through extracellular vesicle and tunnel nano tube. Such pathogenic mtDNA aberrations are likely to increase and frequently be homoplasmic in metastatic cancer cells and, intriguingly, in normal cells in the tumor microenvironments as well. Distinct characteristics of these abnormalities in mtDNA may provide a new path for cancer therapy. We recently tested this hypothesis with a few PIP-TPP conjugates targeting mtDNA mutations to induce mutants reduction in heteoplasmic cells or apoptosis in homoplasmic or near homoplasmic cells in vivo model without major adverse effects. This finding reaffirms the feasibility of such a PIP-TPP-based mtDNA-targeting approach for anticancer therapy as well as perhaps cancer risk prevention. However, the absence of known mtDNA mutation hotspots limits the clinical application of somatic mutation-targeted PIP-TPPs. Thus, we designed CCCh-1005-TPP to selectively target a frequent ATP6 gene variant and often oncogenically homoplasmic in the associated with hypertrophic cardiomyopathy, colon, breast and ovarian cancer risk and found its anticancer effect in mouse xenograft models. Here we study preclinical trial of CCCh-1005-TPP, a promising novel anti-cancer agent for clearing abnormal mtDNA by reactivating mitochondrial quality control surveillance of mitophagy. Given those mechanistic insights may provide a promising therapeutic or maybe preventive approach of the pathogenic mtDNA removal in homoplasmic or heteroplasmic cells. Additional caveat is that this strategy may also use not only for cancer but also many other mitochondria related diseases, such as neurodegenerative, diabetic, renal, muscle and hearing loss diseases as well as aging. Citation Format: Hiroki Nagase. Cancer therapeutic and prevention strategy targeting mutated mitochondria DNA [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5980.

In-situ construction of In2O3/In2S3-CdIn2S4 Z-scheme heterojunction nanotubes for enhanced photocatalytic hydrogen production

Semiconductor photocatalysis was considered as an ideal solution to energy shortages. Herein, a novel ternary In2O3/In2S3-CdIn2S4 (IOSC) nanotube (NTs) photocatalyst was successfully constructed via in situ growth of In2S3 and CdIn2S4 nanosheets onto In2O3 skeleton. It was used for the efficient and stable photo-production of hydrogen from water splitting. The rationally designed IOSC NTs displayed significantly enhanced photocatalytic H2 production under visible light irradiation (≥420 nm), with the highest H2 yield determined to be 2892 μmol·g−1, which is much higher than that of pristine In2S3 and In2O3/In2S3 (IOS) NTs. Cyclic testing has shown that the IOSC2 product remains stable after four cycles of repeated use. The enhanced photocatalytic activity was contributed by its tightly bound tube-nanosheets heterogeneous structure and superior light absorption. Photoelectrons transfer in IOSC2 follows a Z-scheme mechanism, which greatly facilitates its utilization of photogenerated electrons and prevents CdIn2S4 from undergoing photo-corrosion affecting material stability. This work demonstrates the key role of in situ growth in the interface design of ternary heterostructures.

Stability analysis of multi-trigger nano tube sandwich structures considering thermal and magnetic effects

This research investigates the stability analysis of multi-trigger nanotube-based sandwich structures that carry fluid subjected to external stimulus. Acrylic-based material and magnetorheological elastomers (MRE) are considered multi-trigger cores in which the external stimulus alters the mechanical properties of the core and, subsequently, the sandwich structures. The system is subjected to an external magnetic field while the ambient temperature varies. The results demonstrate that incorporating a multi-trigger viscoelastic core can accelerate the divergence instability of the non-conservative system while delaying its flutter. Additionally, the impact of the external magnetic field, as a control parameter, for the frequency and stability region of the MRE is more significant than that of the Acrylic-based material. Furthermore, employing Acrylic-based material with a higher shear modulus in a constant magnetic field leads to a more stable system. Moreover, the effect of the external magnetic force on stability is affected smoothly by the ambient temperature. Finally, the influence of temperature on stability is nearly the same for both MRE and Acrylic-based material, with a more pronounced effect observed in systems with larger length-to-diameter ratios.

Mechanical properties of bilayer WS2 and Graphene-WS2 Hybrid composites by molecular dynamics simulations

In the present work, by using molecular dynamics (MD) simulations, we investigate the mechanical properties of different nanostructures that may be core elements in next generation flexible/wearable photovoltaic devices, namely double layer WS2 nanosheets (DLNS), graphene/WS2 (layer) composites and graphene/WS2 nanotube (NT) composites. Our results reveal that the mechanical properties of DLNS deteriorate when compared to those of monolayer WS2. Owing to graphene’s reinforcement action, the mechanical properties of graphene/WS2 (layer) composite with both layers deformed are superior than those of WS2, even though inferior than those of bare graphene. If stress is applied only to the graphene layer, the graphene/WS2 composite retains the most of the strength and toughness of monolayer graphene, decreasing the fracture strength and Young’s modulus by only 9.7% and 16.3%, respectively. Similarly, in the case of the graphene/WS2 NT composite the mechanical strength and toughness experience a reduction compared to monolayer graphene, specifically by 15% and 53% for fracture strength and Young’s modulus, respectively. Considering the market’s keen interest in nanomaterials, particularly van der Waals (vdW) ones, for flexible and wearable photovoltaic devices, the findings presented here will significantly enhance the effective utilization of vdW composites.

The Investigation of KH560 Coupling Agent with Carbon Fiber One Step Dipping Method Compared with Functionalized Multi Walled Carbon Nanotubes

Interlaminar and interfacial properties of composites are important parameters for any application, extensive research has been out bursting to enhance the above properties using nanotubes (NTs) as an alternate solution to minimize delamination of laminates. This research focused on significance of functionalized engineering materials for better efficiency in industries, especially stealth technology. Silane-coupling agent “3-glycidyletheroxypropyl-tri methoxy silane, KH-560” is one module among five modules designed in this work. Five modules are considered as (M1, M2, M3, M4 & M5) with (0.5wt% of AMINE, CARBOXYL, multi wall carbon nano tubes (MWCNTs), 5% KH-560 treated carbon laminate and finally with base carbon fiber). PAN-based 12k carbon fiber as base fiber with functionalized and non-functionalized nanocomposite are incorporated as fillers in the epoxy laminates fabricated using vacuum bagging technique. Findings indicated 5% KH-560 silane treated carbon fiber (module M5) showed best results such as properties with 39%,55% and 20% in “tensile, flexural and interlaminar shear strength (ILSS)” respectively. FESEM analysis is conducted to understand morphology of the laminates.

Presentation of Multi Inputs Full Ternary Comparator with Carbon Nano Tube Field Effect Transistor

Presentation of Multi Inputs Full Ternary Comparator with Carbon Nano Tube Field Effect Transistor

Shrinkage cracking and mechanical properties of cementitious composites produced with multiwall carbon nano tubes and different types of polypropylene fibres

This study was conducted to experimentally demonstrate the control the nano-, micro- and macro-scale cracking in cement-based composites by using nano-, micro- and macro-scale fibres. While micro, macro and hybrid system polypropylene (PP) fibres were used in concrete designs, micro-scale PP and multi-walled carbon nano tubes (MWCNT) were utilized in mortar mixtures. The progression of the cracks was monitored in accordance with a well-known standard and also with a modified method which enabled the investigation of plastic and restrained shrinkage. Fracture energy, flexural strength, compressive strength, modulus of elasticity and ultrasonic pulse velocity of the samples were also determined as the mechanical properties of the composites. Results showed significant improvements in the reduction of cracks, especially with hybrid fibres system.

Modeling, Optimization, and Simulation of Nanomaterials-Based Organic Thin Film Transistor for Future Use in pH Sensing.

Applications of Organic Thin Film Transistor (OTFT) range from flexible screens to disposable sensors, making them a prominent research issue in recent decades. A very accurate and exact pH sensing determination, including biosensors, is essential for these sensors. In this present research work, authors have proposed a nanomaterial-based OTFT for future pH monitoring and other biosensing applications. This work presents a numerical model of a pH sensor based on Carbon Nano Tubes (CNTs). Sensing in harsh conditions may be possible with the CNTs due to their strong chemical and thermal resilience. This research work describes the numerical modeling of Bottom-Gate Bottom-Contact (BGBC) OTFTs with a Semiconducting Single-Walled Carbon Nanotube (s-SWCNT) and C60 fullerene blended active layer. The design methodology of organic nanomaterial-based OTFTs has been presented with various parameter extraction precisely its electrical characteristics, modeled by adjusting the parameters of the basic semiconductor technology. For an active layer thickness of 200 nm, the drain current of the highest-performing s-SWCNT:C60 -based OTFT structure was around 4.25 A. This allows for an accurate representation of the device's electrical characteristics. Using Gold (Ag) Source/Drain (S/D) and back-gate electrodes as the medium for sensing, it has been realized how the thickness of the active layer impacts the performance of an OTFT for pH sensor applications.

Acute Genetic Damage Induced by Ethanol and Corticosterone Seems to Modulate Hippocampal Astrocyte Signaling.

Astrocytes maintain CNS homeostasis but also critically contribute to neurological and psychiatric disorders. Such functional diversity implies an extensive signaling repertoire including extracellular vesicles (EVs) and nanotubes (NTs) that could be involved in protection or damage, as widely shown in various experimental paradigms. However, there is no information associating primary damage to the astrocyte genome, the DNA damage response (DDR), and the EV and NT repertoire. Furthermore, similar studies were not performed on hippocampal astrocytes despite their involvement in memory and learning processes, as well as in the development and maintenance of alcohol addiction. By exposing murine hippocampal astrocytes to 400 mM ethanol (EtOH) and/or 1 μM corticosterone (CTS) for 1 h, we tested whether the induced DNA damage and DDR could elicit significant changes in NTs and surface-attached EVs. Genetic damage and initial DDR were assessed by immunolabeling against the phosphorylated histone variant H2AX (γH2AX), DDR-dependent apoptosis by BAX immunoreactivity, and astrocyte activation by the glial acidic fibrillary protein (GFAP) and phalloidin staining. Surface-attached EVs and NTs were examined via scanning electron microscopy, and labeled proteins were analyzed via confocal microscopy. Relative to controls, astrocytes exposed to EtOH, CTS, or EtOH+CTS showed significant increases in nuclear γlH2AX foci, nuclear and cytoplasmic BAX signals, and EV frequency at the expense of the NT amount, mainly upon EtOH, without detectable signs of morphological reactivity. Furthermore, the largest and most complex EVs originated only in DNA-damaged astrocytes. Obtained results revealed that astrocytes exposed to acute EtOH and/or CTS preserved their typical morphology but presented severe DNA damage, triggered canonical DDR pathways, and early changes in the cell signaling mediated by EVs and NTs. Further deepening of this initial morphological and quantitative analysis is necessary to identify the mechanistic links between genetic damage, DDR, cell-cell communication, and their possible impact on hippocampal neural cells.

Design and performance investigation of CIGS/SWCNT tandem solar cell for efficiency improvement

This research work demonstrates the design and simulation of highly efficient tandem solar cell by using SCAPS-1D software. This tandem solar cell has been designed with a higher bandgap Copper Indium Gallium Diselenide (CIGS) absorber as a top cell and a lower bandgap Single Wall Carbon Nano Tube (SWCNT) absorber as a bottom cell, which are arranged in the series connection. Firstly, both top and bottom solar cells were analysed under standalone afterward, tandem configuration was developed with the top cell illumined by AM 1.5 spectrum and the bottom cell illumined by AM 1.5 filtered by top cell spectrum. The effects of absorber thickness, doping density, and bandgap on the output characteristics of the solar cell are also investigated. The current matching of both cells is attained by tuning the bandgap and thickness of Cu(In1-xGax)Se2 absorber of the upper cell. The remarkable efficiency of 38.91 % (Voc = 1.3441 V, Jsc = 37.87 mA/cm2 and FF = 76.41 %) is attained of the proposed CIGS/SWCNT tandem device at a thickness of 860 nm and 2000 nm for absorber of top and bottom cell respectively. The results of this research suggest a route for the fabrication of CIGS/SWCNT tandem solar cell with high efficiency.

TiO2 nanocone photoanodes by Ar ion-beam etching and physics-based electrochemical impedance spectroscopy

TiO2 nanocone (NC) arrays were produced by argon ion beam etching of nanotube (NT) arrays prepared by Ti anodizing. The anti-reflection performance of NC arrays was enhanced by anodizing a 1 μm-thick Ti film deposited on a p-type silicon substrate. The NC morphology was maintained upon heat treatment up to 400 °C, where the anatase phase was formed. Higher temperature treatments resulted in agglomeration and the formation of the rutile phase. The photoelectrochemical performances of the NC and NT arrays on Ti/Si substrates and the NTs on the Ti disk, both annealed at 400 °C, were compared. The photocurrent curves of the samples on Ti/Si were qualitatively different from NT on Ti. Impedance spectroscopy revealed that the response is dominantly from the p-Si substrates, which can be almost ideally described by the diffusion-recombination governed by the minority electronic carriers. NT on Ti can be characterized by the transmission line model for nanoporous electrodes where the transverse and interfacial capacitances are described by Havriliak-Negami capacitance functions with fixed exponents of either 1 and ½ at high- and low-frequency limits. The model then powerfully deconvolutes TiO2 response from the limited information at the low frequencies for NT and NC on Ti/Si, which can be related to the photoelectrochemical performance. Mott-Schottky analysis of well-defined capacitance parameters from the Havriliak-Negami function allows the physics-based description of the spatially and energetically distributed dopant defects in nanostructured materials.

Lacunary polyoxometalates-induced controllable synthesis of Fe2O3/Si-FeWO4 heterostructure nanotubes for selective sensing of m-xylene

Metal oxide-based gas sensors encounter challenges in effectively detecting hazardous benzenes due to their stability and structural similarities. Here we report an innovative in situ growth method for synthesizing Fe2O3/Si-FeWO4 heterostructure nanotubes (NTs) using highly negatively charged multivacant lacunary TBA4H6[SiW9O34]·2H2O (α-SiW9) and Fe3+ as precursors. A two-step process involving electrospinning followed by a thermal oxidation method was employed to synthesize a series of the uniform Si-FeWO4 decorated Fe2O3 heterostructure NTs. Considering the rich Fe2O3/Si-FeWO4 active interfaces, rapid electron transfer, and high specific surface area, the optimal Fe2O3/Si-FeWO4 based sensors demonstrate significantly higher sensitivity (S = 27.5) towards 50 ppm m-xylene in comparison to pristine Fe2O3 (S = 1.8). Furthermore, the Fe2O3/Si-FeWO4 exhibits excellent stability, humidity resistance, and high selectivity for m-xylene. This work offers an efficient, cost-effective strategy to synthesize Fe2O3/Si-FeWO4 heterostructure NTs, with prospects for synthesizing other advanced sensing heterostructure nanomaterials with lacunary polyoxometalates as precursors.

Iridium nanoparticles supported on polyaniline nanotubes for peroxidase mimicking towards total antioxidant capacity assay of fruits and vegetables

In this study, a straightforward approach is presented for the first time to anchor Ir nanoparticles on the surface of uniform polyaniline (PANi) nanotubes (NTs), which can be used as an efficient peroxidase (POD)-like catalyst. The morphology and chemical structure of the PANi-Ir nanocomposite are characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffractometer (XRD), Raman and X-ray photoelectron spectroscopy (XPS) measurements. Owing to the strong interaction between Ir nanoparticles and PANi, a remarkable catalytic enhancement is achieved compared to the bare Ir black catalyst and individual PANi NTs, dominating withan electron transfer mechanism. Furthermore, an efficient colorimetric sensor for ascorbic acid (AA) is developed with a low detection limit of 1.0 μM (S/N = 3), and a total antioxidant capacity (TAC) sensing platform is also constructed for the rigorous detection and analysis of fruits and vegetables.

An Experimental Investigation on Performances and Emission Characteristics in a Multi-Cylinder Diesel Engine Using Nahar Oil Biodiesel Blended With Carbon Nano Tube

In recent years, the number of automobiles has drastically increased. As a result, the need for energy in the transportation sector is continuously rising. Additionally, using fossil fuels results in many hydrocarbon emissions, carbon monoxide, carbon dioxide, and particulate matter, spoiling the environment. Renewable energy sources like solar power, biodiesel, wind turbine, bioethanol, methanol, hydrogen, and various biomasses from wastes become a great subject of interest. This paper includes biodiesel production from Nahar oil with two-step transesterification and the performance and exhaust emission in a four-cylinder diesel engine fueled with double-walled carbon nanotubes blended with Nahar oil biodiesel. In this case, the B30 blend of Nahar oil biodiesel is taken as base fuel and different proportionate carbon nanotubes blends are compared with pure diesel. The performance analysis is done in a multi-cylinder test engine setup, and the emission of different exhaust gases is considered. The outcomes from the tests demonstrate that Nahar oil biodiesel and its mixes with carbon nanotubes can substitute diesel engines in the future when nonrenewable energy source stores become compromised.

A Review of Development of Chemical Sensors

A comprehensive summary of the most recentre search concentrating on chemical sensors utilizing nano tubes,Nano rods,Nano belts, and nano wiresis given in this article. The experimental principle, sensor device design,sensor mechanism, and multiple significant conclusionsreceivethevastmajorityofourattention.Thefollowingfoursectionsprovide additional information on the creation of chemical sensors based on nanostructured materials: nanotube sensors, Nano rod sensors, Nano belt sensors and Nano wire sensors. Weconcludethisreviewwithpersonalperspectivesonthedirectionstowardswhichfuture research on nanostructured sensors might be directed. At ambient temperature, the nanotube sensors show a far faster response time and a significantly higher sensitivity than the current solid-state sensors. Reversibility of the sensor can be obtained by heating it to a high temperature or by slowly recovering under ambient conditions. Over the past decade, synthesized nanomaterial’s, such as carbon nanotube, nanoparticle, quantum dot, and nanowire, have already made breakthroughs in various fields, including biomedical sensors. Enormous surface area-to-volume ratio of the Nano materials increases sensitivity dramatically compared with macro-sized material. Herein we present a comprehensive review about the working principle and fabrication process of nanowire sensors. Then anotube sensor sex hibit a fast response and asubstantially higher sensitivity than thatofexistingsolid-statesensorsatroomtemperature.Sensorreversibilityisachievedbyslow recovery under ambient conditions or by heating to high temperatures.Synthesized Nano materials, including carbon nanotubes, nanoparticles, quantum dots, and nanowires, have already achieved significant advances in a number of sectors, including biological sensors, during the last ten years. When compared to macro-sized material, the nanoparticles' enormous surface area-to-volume ratio significantly boosts sensitivity. We provide a thorough overview of the fabrication process and operating principle of the nanowire sensor here. Recent advances including self-powering, reusability, sensitivity in high ionic strength solvent,andlong-term stabilityaresurveyedandhighlightedas well.Nanowire isexpectedtolead significant improvement of biomedical sensor in the near future.Advantages and disadvantages of the sensors are provided along with brief descriptions. An electrical device that monitors changes in a quantity, such as voltage, temperature, pressure, or humidity, is called a sensor. As a result, classification is done according to the attribute that a sensor measures. A temperature sensor detects even the smallest variations in its environment or shifts in temperature, such as hot or cold weather. Microelectronic manufacturing techniques have been used to manufacture chemical and electrochemical sensors.Thedevelopment ofchemical sensors has been spurred forward by the recentadvancesinmicromachingtechnology.Chemicalsensorresearchhasadvancedthanksto micro machining methods like sacrificiallayers, plasmaetching, andchemicalanisotropicetching. These methods enable the creation of low mass, low power driven devices as well as controlled working conditions and temperature. Researchersbecameinterestedinthesecarefullychoseninvitronanostructureswhentheywere combined with nanomaterials because the improved properties of these nanostructures led to advances inthe analytical performance of chemical and biosensors. Thisstudycoversthe latest advancements in recognition elements that are integrated in to chemical sensors and bio sensors used in the food, medical, and environmental domains. These elements include both traditional ones like enzymes and antibodies as well as more modern ones like aptomers and phages.Cyclic voltammetry and electron microscopy are frequently used in the characterization of chemically modified sensors and biosensors because they enable the confirmation of electrode mechanisms and surface morphologies. X-ray photoelectron spectroscopy (XPS), among other methods, is a special tool for obtaining information on the sensor surface that is qualitative, quantitative/semi-quantitative, and speciation-related. However, XPS is still not widely applied in this industry. The purpose of this work is to review a few selected studies that demonstrate how wellXPSperformswhencharacterizingthetopsurfacelayersofbiosensorsandchemically Modified sensors. The reader is provided with the necessary background information in a brief introduction to X-ray photoelectron spectroscopy. The use of XPS to characterize sensors appropriate for environmental and food analysis is highlighted.

Efficient flexible dye-sensitized solar cells from rear illumination based on different morphologies of titanium dioxide photoanode

The TiO2 with nanoparticles (NPs), nanowires (NWs), nanorods (NRs) and nanotubes (NTs) structures were prepared by using a in-situ hydrothermal technique, and then proposed as a photoanode for flexible dye-sensitized solar cell (FDSSC). The influences of the morphology of TiO2 on the photovoltaic performances of FDSSCs were investigated. Under rear illumination of 100 mW·cm−2, the power conversion efficiencies of FDSSCs achieved 6.96%, 7.36%, 7.65%, and 7.83% with the TiO2 photoanodes of NPs, NWs, NRs, and NTs and PEDOT counter electrode. The FDSSCs based on TiO2 NRs and NTs photoanodes have higher short circuit current densities and power conversion efficiencies than that of the others. The enhanced power conversion efficiency is responsible for their nanotubes and rod-shaped ordered structures, which are more beneficial to transmission of electron and hole in semiconductor compared to the TiO2 nanoparticles and nanowires disordered structure.

Influence of silica rich HNT/MoS2 hybrid reinforcements on mechanical, wear and corrosion characteristics of magnesium AZ31 alloy

This article examines the effects of combining silica-rich Halloysite Nano Tube (HNT) and Molybdenum di Sulphide (MoS2) as hybrid reinforcements, dispersed at volumes of 2, 4, and 6%, on the surface of AZ31 alloy through the application of the friction stir process (FSP). The prepared composites were analysed to evaluate their microstructure, mechanical properties, wear resistance, and corrosion characteristics. Microstructural observations indicate the occurrence of rapid recrystallization, resulting in reduced grain size and uniform dispersion. The surface composite demonstrates an increasing trend in hardness with the addition of HNT, while hardness decreases with the inclusion of MoS2. The micro tensile test results exhibits that the composite exhibits an increasing trend in strength, while the micrograph of the fractured surface of the micro tensile specimens reveals reduced ductility. The composite displays enhanced wear behaviour with the increasing volume percentages of HNT and MoS2 particles. Solid lubricant nature of the secondary reinforcement and enhanced hardness due to HNT addition and FSP leads to higher wear resistance of the developed hybrid composite. Additionally, the corrosion rate decreases with the addition of HNT, whereas higher concentrations of MoS2 lead to increased corrosion.