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Breast cancer (BC) is one of the primary causes of death among females worldwide. It can affect a woman at any age after puberty, but the risk of developing the disease increases with age. An early diagnosis and the implementation of an appropriate therapeutic strategy are the two most essential aspects in assuring a favorable prognosis for patients diagnosed with any cancer. There has been significant development in cancer immunotherapy over the past few years. It is among the most effective approaches to fighting cancer and boosts the immune system. In the preclinical setting, immunotherapy using checkpoint blockade antibodies and antigen receptor T cells has shown promising results in BC. Despite this, developing safe and effective immunotherapy against breast cancer is challenging because several novel antigens are poorly immunogenic. Regrettably, conventional immunotherapy confronts further obstacles, such as its inability to trigger the anti-tumor response sufficiently. Most tumors have low immunogenicity due to their origin in healthy cells, making it difficult for the immune system to recognize them as foreign invaders. Additionally, the clinical use of immunotherapy for BC has experienced significant drawbacks, including poor immune responses due to insufficient antigen delivery to the immune cells and uncontrolled immune system regulation, which can promote autoimmunity and nonspecific inflammation. To address these challenges, nanomaterial-based immunotherapy has recently emerged as a potent tool against BC. Scientists have been enthralled by the potential of nanomaterial in BC immunotherapy for decades due to its significant benefits over traditional immunotherapy. Over the past few decades, there has been a considerable increase in the research and application of nanomaterial-based antigens/adjuvants in BC immunotherapy. This review focuses on current advances in BC immunotherapy strategies by focusing on recent breakthroughs in nano immunotherapy.

In the present work, a lead-free perovskite solar cell was designed using methylammonium tin iodide (CH3NH3SnI3), poly-3- hexylthiophene and titanium dioxide (TiO2) as absorber layer, hole transport layer and electron transport layer respectively. Perovskite solar cells have made impressive strides recently, and their performance has significantly improved. A fundamental n–i–p planar heterojunction structure of photovoltaic cells was designed and simulated with solar cell capacitance simulation software (Scaps-1D). In this study, different parameters such as thickness, acceptor density, temperature and defect density were varied to improve the device performance. Optimum values of different parameters were used to attain good results for the photovoltaic device such as power convergence efficiency (PCE), V OC, fill factor and J SC of 27.54%, 1.0216 V, 86.56% and 31.14 mA/cm2, respectively. The acceptor density was varied from 1 × 10−12 to 1 × 10−20 cm−3 for the proposed device structure. The PCE of this device structure increased when different charge transport materials were used. This simulation study showed that the proposed cell structure could be used to construct a photovoltaic cell with a higher efficiency.

Herein, we report the synthesis, characterization, and gas sensing properties of zinc oxide (ZnO) nanoflowers grown by facile simple solution process. The synthesized ZnO nanoflowers were examined by various techniques to explore their structural, morphological, optical, compositional and gas sensing properties. The details morphological and structural characterizations revealed that the synthesized material possessed flower-shaped morphologies in the nanoscale range with a wurtzite hexagonal crystal structure of ZnO. The high-intense peaks of the synthesized ZnO nanoflowers confirmed high crystallinity. Furthermore, the synthesized ZnO nanoflowers were used as an electrode material to fabricate a facile and low-cost gas sensor to detect hydrogen sulphide (H2S). At an ideal working temperature of 150 °C, the ZnO nanoflowers electrode-based gas sensor displayed remarkable selectivity, good response (48 s), and recovery (97 s) time. Moreover, the fabricated gas sensor exhibited a maximum gas response of 139 (Rg/Ra) towards 50 ppm hydrogen sulphide gas at 150 °C. The unique performance of the ZnO nanoflowers-based gas sensor was attributed to the large surface area of the ZnO nanoflowers, which enabled the fabricated sensor to be a contender for the detection of H2S gas among the wide variety of reported sensors.

In this research work, we have synthesized amorphous Se85Te6Bi9 Chalcogenide Glasses (ChGs) using Melt Quenching Technique. The glassy nature of the synthesized specimen was confirmed by the DSC thermogram plotted at the heating rate of 20 K/min. The nano-thin films of such synthesized samples at two disparate working pressures (1 torr and 3 torr) of ambient argon gas were made using the Physical Vapour Condensation Technique on the ultrasonically cleaned glass substrates. During the synthesis process of nano-thin films substrate temperature (77 K) was kept constant using liquid nitrogen and the thickness of prepared thin films was 40 nm. The morphological analysis of the prepared nanochalcogenide thin films using FESEM confirmed the nanochalcogenide particle size ranges from 20–80 nm. More aggregation and reduction in particle size on the substrates were observed with an increase in working pressure for Se85Te6Bi9 nano-thin films. HRXRD pattern confirmed the amorphous nature of the synthesized nano-thin films. Based on UV-Visible spectroscopy, the optical parameters such as optical absorption coefficients, optical direct band gaps and extinction coefficients were measured for synthesized Se85Te6Bi9 nanochalcogenide thin films. The value of absorption coefficients and extinction coefficients increases with the increase of ambient argon pressure, whereas the value of the optical direct band gap increases with increasing working pressure due to the quantum size effect and dominance of coulombic interactions. The estimated value of optical direct band gaps are 1.37 eV and 1.47 eV at 1 Torr and 3 Torr respectively making our synthesized nano-thin films a preeminent candidate for solar cell applications and other photonic devices.

A novel electrochemical aptasensor modified with the nanocomposite of porous carbon nanospheres and Au urchins as the signal amplification and immobility platforms for aptamer was successfully constructed for ultrasensitive and selective determination of streptomycin. The streptomycin aptamer was fixed on the surface of the nanocomposite via the strong Au–S bond between Au urchins and aptamer. The target binding-induced conformational change of aptamer resulted in signal attenuation, which was expressed as “ΔI = IBSA − Istreptomycin.” Based on the synergic signal amplification platform, the as-prepared aptamer-based sensor showed a wider linearity to streptomycin from 0.01 to 350 ng/mL with a low detection limit of 5.0 pg/mL under the optimized condition. Finally, the aptasensor was operated in milk and honey to detect streptomycin. This study has provided a facile way to develop highly sensitive, effective and efficient aptamer-based electrochemical sensors for the detection of antibiotics at very low concentration.

Herein, a microwave-assisted approach for the synthesis of manganese (II) (Mn2+)-doped bismuth ferrite (BMFO) nanoparticles is presented. Various techniques were used to examine the structure, morphology and electrical characteristics of the as-synthesized BMFO nanoparticles. X-ray diffraction and Raman analysis revealed a rhombohedral distorted perovskite structure with space group R3c. The crystallite size of BMFO was found to be 18.77 nm. Scanning electron microscopy studies of the BMFO nanoparticles showed the highly agglomerated nature of the particles. The ultraviolet diffuse reflectance spectrum of BMFO revealed a bandgap of 1.56 eV, which was smaller than the bandgap of pure bismuth ferrite (2.41 eV). The methyl orange (MO) dye degradation behavior of the synthesized BMFO was examined for a dye sample solution in the presence of solar radiation. After 120 min, irradiation resulted in 81.08% photodegradation of the MO dye. Kinetic studies demonstrated a pseudo-first-order rate mechanism for the photodegradation of the MO dye. The corresponding coefficient of determination R 2 and t 1/2 were 0.92864 and 63.0 min, respectively. Finally, a methodology for the degradation of MO dye using BMFO is proposed.

Herein, we report the facile hydrothermal synthesis and characterizations of ZnO nanorods assembled microflowers and their efficient sensing application for the detection of formalydehyde gas. The synthesized ZnO microflowers were examined by several techniques. The scanning electron microscopy (SEM) was employed to evaluate the surface morphology, X-ray diffraction (XRD) analysis for the crystal structure while the Fourier transformation infrared (FTIR), and Raman-scattering spectroscopy were employed to understand the functional groups in the synthesized material. The optical properties were evaluated by UV-visible spectroscopy Furthermore, the synthesized ZnO microflowers were used as a functional material to fabricate formaldehyde gas sensor which exhibited a high gas response of 113.36 (Rg/Ra) towards 50 ppm formaldehyde gas at 200 °C. The observed response and recovery times for the fabricated sensor were ∼65 s and ∼117 s, respectively. Finally, the enhancement of gas-sensing performance and mechanism were thoroughly discussed. This work revealed that simply prepared ZnO nanostructures can be used to fabricate high-performance gas sensors.

More than 5 million people require medical attention due to burn-related injuries annually. Significant research has been carried out in recent decades to develop approaches to improve the healing of burn wounds. The focus has also been on the development of natural product-based therapeutic remedies for the treatment of burn wounds. This has been done primarily due to multimodal mechanisms exhibited by some promising bioactive molecules of natural origin. Hesperetin is one such molecule that possesses strong anti-inflammatory and antioxidant properties. It is mainly obtained from citrus species. The goal of the current study was to assess how well chitosan gel that contains hesperetin may cure burn wounds. The advantage of using chitosan gel is that it could form a depot at the site and provide a protective therapeutic covering over burn wounds. In the present study, hesperetin-containing chitosan gel was prepared and evaluated for percentage hesperetin content, extrudability, spreadability, and rheological behavior. The preclinical wound healing activity was evaluated using an experimental burn wound model in Wistar rats. The results of the animal experiment showed early and better healing of burn wounds in animals treated with hesperetin-containing chitosan gel. There was 92.79% healing after 14 days of application of hesperetin-containing chitosan gel compared to 69.49% healing observed in the control group. Further, the histopathological evaluation suggested no inflammatory cell infiltration, normal epidermal growth, and normal collagen bundle arrangement in these animals. Overall the results provide proof of concept to establish the wound healing potential of hesperetin-containing chitosan gel against burn wounds.

In recent years, the advancement of solar cell technology is increased by leaps and bounds and it is also used to achieve a solution for the worldwide huge need for generation of energy and electricity. The colloidal quantum dot (CQD) offers a size-tuned bandgap and materials processing compatibility with a range of substrates. QDSC (Quantum dot solar cell) have advantages such as low cost, high efficiency, and replaces bulky material (Cadmium Selenide, Lead Selenide etc over traditional solar cell. “Despite these advantages, it lags due to carrier recombination in the Quasi-Neutral Region (QNR). The performance of the solar cell greatly depends on the electron transport layer (ETL) and hole transport layer (HTL). To investigate the feasibility of a highperformance device, a comparative investigation of the PbS-EDT and Spiro-OMeTAD hole transport layers has been done. For this, we have varied the various parameters upon which performance of solar cells is dependent in order to maximise the performance. All simulations study has been performed using SCAPS-1D simulator. The overall maximum optimized performance of the photovoltaic solar cell of 16.29% is obtained using TiO2 and PbS-TBAI(tetrabutylammonium iodide) as a ETL and absorber layer respectively. Our research demonstrates that an efficient quantum dot solar cell could be fabricated experimentally using the optimal device structure.

In the present work, a simple, cost effective, and biofriendly methodology was reported to prepare ZnO nanorods used as the photoanode materials for the dye-sensitized solar cells (DSSCs) in combination with coffee extract as a dye and carbon as a counter electrode made by candle flame. The prepared nanostructures were well characterized by XRD, Raman, FESEM, and TEM measurements. The XRD, Raman and TEM results confirmed that the ZnO nanorods were crystallized in the hexagonal phase and possessed single phase nature. Morphological studies performed by FESEM and TEM analyses showed that the ZnO have rods like morphology which were uniform and dense. The length and diameter of the prepared nanorods were ~45 nm and ~1 μm, respectively. The results showed that the ZnO nanorods electrode exhibited a power conversion efficiency (PCE) of DSSCs with a maximum value of 0.54% having a Voc and Jsc of ~0.272 V, and 7.4 mA/cm2, respectively. Significantly, this technique could be used for a large scale production using existing economical, biosafe, and highly effective DSSCs fabrication technique. Development of new-DSSCs (with coffee as natural dye and carbon from candle as counter electrode) using ZnO nanorods open up the way for a diversity of applications.

This study investigates unique and specific properties of the lanthanum based zinc molybdate nanocomposite material. The lanthanum zinc molybdate nanocomposite material was synthesized using a simple and low cost “co-precipitation” method. The synthesized nano materials had structural, vibrational and morphological properties, determined by X-ray diffraction, fourier-transform infrared spectroscopy and field emission scanning electron microscopy. The synthesized nanomaterial was characterised using a range of techniques. X-ray diffraction was used to determine a particle size of 65.7 nm of the disc shaped hexagonal particle. Further characterisation was done using UV-visible spectroscopy and band gap energy analysis. The band gap value was found to be 3.58 eV. The nanocomposite also exhibited antibacterial activity against bacterial strains of Escherichia coli and Staphylococcus aureus. In the presence of light and air, nanoparticles of lanthanum zinc molybdate nanocomposite were found to inhibit the growth of Escherichia coli due to generation of singlet oxygen and hydrogen oxide radical. However, the same was not observed for S. aureus. Photocatalytic property of lanthanum zinc molybdate nanocomposite was determined using an aqueous solution of methylene blue dye. lanthanum zinc molybdate nanocomposite showed photo-degradation due to the formation of singlet oxygen and hydrogen oxide radical. Complete decolourization of blue colour of the of methylene blue solution at 6 pH was attained, using 40.0 mg lanthanum zinc molybdate nanocomposite, with a constant time interval. With time, the activity of lanthanum zinc molybdate nanocomposite was also found to decrease due to the formation of a hydrogen oxide layer on the surface of the nano material. This could be washed off with ethanol and distilled water. After drying, the catalytic nano particle could be reused for another reaction.

In this work, a facile low temperature solution route was reported for the preparation of monodisperse Fe3O4 nanoparticles and their reduced graphene oxide (RGO) based nanocomposites and used as anticancer agents. X-ray diffraction spectroscopy XRD and Raman studies revealed the high crystalline nature of the Fe3O4 nanoparticles and the presence of characteristic peaks of RGO in Fe3O4/RGO nanocomposites. Transmission electron microscopy (TEM) micrographs showed the morphology of the RGO nanosheets decorated by Fe3O4 nanoparticles with sizes ranging from 10–15 nm. High resolution (HR)-TEM study revealed the formation of Fe3O4/RGO nanocomposites with the interplanar spacing corresponding to the (311) plane of Fe3O4. The anti-cancer properties of Fe3O4/RGO nanocomposites against A549 cells were investigated using MTT, NRU assay, morphology of cells, and ROS generation analyses and compared with the pure Fe3O4 nanoparticles. In comparison between both the pure Fe3O4 and Fe3O4/RGO nanocomposites, more damage to the A549 cells resulted from the nanocomposites at a similar concentration of 100 μg/ml. The cell viability test showed that 36% cell viability was observed at a concentration of 100 μg/ml for Fe3O4/RGO nanocomposites. Additionally, the percentage of ROS generation for Fe3O4/RGO nanocomposites was higher than that of Fe3O4 at a concentration of 100 μg/ml. These results suggested that the as-synthesized nanocomposites might be a potential candidate for future anticancer agents.

Recently, Dye-sensitized solar cells (DSSCs) have very attracted a huge deal of industries and academics owing to its number of properties including cost-effectiveness, and practically high power energy conversion efficiency. However, there is always a need to develop new research technologies to increase solar cells efficiency based on oxide heterojunctions. In this work, a fast, environment friendly and economic route were used to prepare TiO2, and their nanocomposites containing reduced graphene oxide (RGO), and carbon nanotubes (CNTs) for the fabrication of DSSCs device onto ITO substrates. The prepared nanostructures were well characterized by X-Ray diffraction (XRD), FESEM, TEM, and Raman measurements. XRD analysis confirmed that TiO2 nanoparticles were crystalline with tetragonal phase. Morphological studies performed by FESEM and TEM images showed that the TiO2 possessed spherical morphology which were uniform and densely covered on the surface of the RGO nanosheets. The DSSCs were fabricated using prepared TiO2 nanoparticles and nanocomposites with RGO and CNTs as working electrode. The results revealed that the DSSCs fabricated using nanocomposites showed enhanced performance as compared with the pure samples without RGO. In particular, the TiO2/CNTs (0.5 wt%) nanocomposites electrode exhibited highest power conversion efficiency (PCE) of DSSCs with a maximum value of 0.679% compared to 0.269% of DSSC with pure TiO2, and 0.472% of DSSC with TiO2/RGO. This method would provide a pathway to produce a low-cost technological process to develop high efficiency DSSCs.

Formaldehyde (HCHO) sensing plays a critical role for indoor environment monitoring in smart home systems. Inspired by the unique hierarchical structure of cactus, we have prepared a ZnO/ANS-rGO composite for room-temperature (RT) HCHO sensing, through assembling hollow cactus-like ZnO nanorods with 5-aminonaphthalene-1-sulfonic acid (ANS)-modified graphene nanosheets in a facile and template-free manner. Interestingly, it was found that the ZnO morphology could be simply tuned from flower clusters to hollow cactus-like nanostructures, along with the increase of the reaction time during the assembly process. The ZnO/ANS-rGO-based sensors exhibited superior RT HCHO-sensing performance with an ultrahigh response (68%, 5 ppm), good repeatability, long-term stability, and an outstanding practical limit of detection (LOD: 0.25 ppm) toward HCHO, which is the lowest practical LOD reported so far. Furthermore, for the first time, a 30 m

This work presents a unidirectional, co-circularly polarized (CP), printed antenna with highly decoupled or isolated transmit (Tx) and receive (Rx) ports for 2.4 GHz in-band full duplex (IBFD) applications. The presented antenna topology is based on four similar and sequentially rotated trimmed patches with right hand circular polarized (RHCP) characteristics. The symmetrical placement of two Tx patches with respect to both Rx elements results in equal levels of self interference (SI) which was suppressed through balanced excitation of Tx mode. This mechanism results in effective suppression of SI at each Rx patch. The residual SI is suppressed further through a second balanced feeding network deployed at Rxport of proposed antenna topology. The employed balanced feeding networks provide superior performance of ≤ 0.5 dB and 6° magnitude and phase imbalances respectively between the two balanced output ports over the bandwidth of interest. The measured results for prototype of presented antenna achieve -10 dB bandwidth of better than 100 MHz for both Tx and Rxports. The measured interport coupling for validation model ≤ −70 dB across the entire bandwidth of 100 MHz. As per best of authors’ knowledge, the presented antenna is the first one to report such reduced levels of interport coupling over the whole impedance bandwidth of planar antenna with unidirectional radiation patterns and co-RHCP characteristics for both Tx and Rx modes across the overlapped bandwidth.

In this work, we report hybrid NiCo2S4@Ni(OH)2 electrode materials on Ni foam by a multi-step hydrothermal approach. The mass capacitance of the prepared sample shows an excellent cycling stability after 10 000 cycles of charge/discharge tests.

Herein, we report a facile synthesis of cauliflower-shaped ZnO structures through a hydrothermal method for efficient gas sensing applications. The ZnO structures were characterized by field emission scanning electron microscopy associated with energy dispersive spectroscopy (EDS), X-ray diffraction and Raman spectroscopy. XRD analysis revealed hexagonal wurtzite phase of ZnO crystals with excellent crystallinity and mean particle size of 45.50 nm. FESEM analysis showed cauliflower-like morphology composed of a large number of hexagonal nanorods. Cauliflower-shaped ZnO structures were used to device resistive sensor devices for NO2, NH3 and H2S gases. Gas responses for NH3 and H2S gases were not impressive even at high operating temperatures ranging from 200–450 °C. In contrast, for NO2 gas the responses were efficiently high even at very low operating temperatures. A maximum gas response of 431.36 was observed at very low operating temperature of 50 °C.

The fabrication and characterization of nanorod-shaped Al-doped ZnO nanostructures are described in this paper. The hexagonal wurtzite phase of ZnO was confirmed by XRD investigation, with efficient doping of Aluminum ions in the ZnO crystal. The length and diameter of the high density produced doped ZnO nanorods were shown to be heterogeneous using FESEM analysis. EDS, FTIR, and Raman spectroscopy examinations validated purity, composition, and vibrational characteristics. Even at very low analyte concentrations, the constructed Al-doped ZnO nanorods modified silver electrode (AgE) displayed exceptional electron mediating characteristics towards phenylhydrazine. The sensitivity, linear dynamic concentration range (LDR) and limit of detection (LOD) were found to be 64.77 μAmM−1cm−2, 0.313–2.5 mM, and 0.313 mM, respectively. As a result of the research described, Al-doped ZnO nanorods appear to be promising candidates for building efficient and repeatable electrochemical sensors in the future.

It is critical to design bifunctional nonprecious electrocatalysts with low costs and high efficiency for hydrogen production. Conventional electrocatalysts, on the other hand, frequently exhibit s...

This paper reports the photoluminescence and nonlinear optical (NLO) properties of Ce2O3–TiO2 nanocomposites synthesized via sol–gel process with different concentrations of cerium. The physical characterization studies by means of XRD indicated for the successful incorporation of Ce into the lattice of TiO2, while the UV-visible spectra for an absorption edge shift of TiO2 to the higher wavelength side following the Ce addition, and FESEM analysis for the morphology and particles sizes of the synthesized materials. On testing of the photoluminescence properties recorded through time-resolved fluorescence (TCSPC) technique, a decrease in the intensity of TiO2 with that of increased Ce concentration was observed and is due to an escalation in the number of oxygen vacancies. Further, the observation NLO properties for Ce2O3–TiO2 was done by a Z-scan technique of 5ns continuous wave (cw) laser at 532 nm, where the involvement of active mechanisms in the nonlinear refraction and nonlinear absorption are due to the saturable absorption (SA) and nonlinear thermal effects.

Herein, we report a facile hydrothermal synthesis of MnO2 nanoparticles anchored multi walled carbon nanotubes (MnO2@MWCNTs) as potential anode materials for lithium-ion (Li-ion) batteries. The prepared MnO2@MWCNTs were characterized by several techniques which confirmed the formation of MnO2 nanoparticles anchored MWCNTs. The X-ray diffraction and Raman-scattering analyses of the prepared material further revealed the effective synthesis of MnO2@MWCNTs. The fabricated Li-ion battery based on MnO2@MWCNTs exhibited a reversible capacity of ~823 mAhg−1 at a current density of 100 mAg−1 for the first cycle, and delivered a capacity of ~421 mAhg−1 for the 60 cycles. The coulombic efficiency was found to be ~100% which showed excellent reversible charge–discharge behavior. The outstanding performance of the MnO2@MWCNTs anode for the Li-ion battery can be attributed to the distinctive morphology of the MnO2 nanoparticles anchored MWCNTs that facilitated the fast transport of lithium ions and electrons and accommodated a broad volume change during the cycles of charge/discharge.

Co-doped ZnO nano-agglomerates were synthesized by a facile solution process. Several characterization techniques revealed the successful doping of the ZnO by Co ions. FESEM results showed the agglomeration of the Co-doped ZnO nanoparticles to form large-sized nano-agglomerates. The diameters of the spherical nanoparticles and the agglomerates were not found to be uniform. The diameters of the nano-agglomerates ranged from ~25 nm–120 nm. XRD spectrum confirmed the Wurtzite hexagonal phase of ZnO in Co-doped ZnO nanoagglomerates. The average particle size for Co-doped ZnO nano-agglomerates was 20.68 nm. The sensing parameters were examined by using Co-doped ZnO nano-agglomerates modified gold electrode through cyclic voltammetric and amperometric analysis. The sensitivity of 70.73 μAmM−1cm−2 and very low-detection limit of 0.2 μM was observed for H2O2. The corresponding linear dynamic concentration range was 0.2–1633 μM. The excellent sensing activities of the Co-doped ZnO nano-agglomerates for H2O2 were attributed to the improved intrinsic electric properties and increased inner defects density, particularly near the interface region.

Herein, a heterostructure of MoS2/CdS/TiO2 nanotube arrays is constructed by successive ionic layer adsorption/reaction of CdS and dipping-assembly of MoS2 on the vertically oriented TiO2 nanotubes prepared by anodization method. The heterostructure is extensively investigated in terms of the composition, morphology, structural, and optical properties. It is observed that the co-modification of TiO2 nanotube arrays with CdS and MoS2 significantly enhances the visible light response and boosts the facile photo-generated electrons’ transfer and charge separation efficiencies. Therefore, the prepared heterostructure photo-anode exhibits significantly enhanced photoelectrochemical properties including photocurrent, open circuit potential, and photo-conversion efficiencies compared with that of pure TiO2 nanotube arrays and CdS/TiO2 nanotube systems. Interestingly, it is found that the MoS2 coatings on the surface of CdS/TiO2 nanotube arrays greatly enhance their photoelectrochemical stability. The presented work demonstrates that MoS2/CdS/TiO2 nanotube heterostructures are a promising material for improved photoelectrochemical properties. A heterostructure of MoS2/CdS/TiO2 nanotube arrays was constructed by successive ionic layer adsorption/reaction of CdS and dipping-assembly of MoS2 on the vertically oriented TiO2 nanotube arrays, and their improved photoelectrochemical properties were demonstrated

In the traditional surface plasmon resonance sensor, the sensitivity is calculated by the usage of angular interrogation. The proposed surface plasmon resonance (SPR) sensor uses a diamagnetic material (Al2O3), nickel (Ni), and two-dimensional (2D) BlueP/WS2 (blue phosphorous-tungsten di-sulfide). The Al2O3 sheet is sandwiched between silver (Ag) and nickel (Ni) films in the Kretschmann configuration. A mathematical simulation is performed to improve the sensitivity of an SPR sensor in the visible region at a frequency of 633 nm. The simulation results show that an upgraded sensitivity of 332°/RIU is achieved for the metallic arrangement consisting of 17 nm of Al2O3 and 4 nm of Ni in thickness for analyte refractive indices ranging from 1.330 to 1.335. The thickness variation of the layers plays a curial role in enhancing the performance of the SPR sensor. The thickness variation of the proposed configuration containing 20 nm of Al2O3 and 1 nm of Ni with a monolayer of 2D material BlueP/WS2 enhances the sensitivity to as high as 374°/RIU. Furthermore, it is found that the sensitivity can be altered and managed by means of altering the film portions of Ni and Al2O3

Herein, we have developed a one-pot methodology to synthesise three types of C-dots and their activated counterparts from three different types of waste plastic precursors such as poly-bags, cups and bottles. The optical studies have shown the significant change in the absorption edge in case of C-dots in comparison to their activated counterparts. The respective variation in the sizes is correlated with the change in electronic band gap values of formed particles. The changes in the luminescence behaviour are also correlated with transitions from the edge of the core of formed particles. The obtained variations in the Stokes shift values of C-dots, and their ACs were used to explore the types of surface states and their related transitions in particles. The mode of interaction between C-dots and their ACs was also determined using solvent-dependent fluorescence spectroscopy. This detailed investigation could provide significant insight on the emission behaviour and the potential usage of formed particles as an effective fluorescent probe in sensing applications.

For the construction of high-performance energy storage and conversion devices, the development of advanced electrode materials with specific nanostructural characteristics is a requirement of the ...

In this paper, star-fruit-shaped CuO microstructures were hydrothermally synthesized and subsequently characterized through different techniques to understand morphological, compositional, structural, crystal, optical and vibrational properties. The formation of star-fruit-shaped structures along with some polygonal and spherical nanostructures was confirmed by FESEM analysis. XRD data and Raman spectrum confirmed the monoclinic tenorite crystalline phase of the CuO with crystal size 17.61 nm. Star-fruit-shaped CuO microstructures were examined for ethanol gas sensing behavior at various operating temperatures and concentrations. The gas response of 135% was observed at the optimal temperature of 225 °C. Due to excellent selectivity, stability and re-usability, the as-fabricated sensor based on star-fruit-shaped CuO micro-structures may be explored for future toxic gas sensor applications.

Root like structured Ni-doped zinc oxide [Zn(1-x)NixO (x = 0.09)] thin films were deposited on a non-conducting glass substrate by indigenously developed spray pyrolysis system at optimized substrate hotness of 573±5 K. Thus obtained Ni-doped ZnO thin films were characterized by UV-visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Atomic Force Microscopy (AFM). XRD result revealed that Ni-doped ZnO has a polycrystalline nature with a hexagonal wurtzite structure. For pure ZnO and Ni-doped ZnO thin films, the particle sizes were 60.9 and 53.3 nm while lattice strain values were 1.56×10−3 and 1.14×10−3, respectively. The film surface showed characteristic root-like structure as observed by the SEM. It was observed that the Ni-doped ZnO thin films were grown in high density along with more extent of branching as compared to pure ZnO thin films but retained the root-like morphologies, however, the branches were more-thinner and of shorter lengths. AFM analysis showed that the surface grains of the Ni-doped samples are homogeneous with less RMS roughness values compared with the undoped ZnO samples. The photocatalytic activity of the prepared thin films was evaluated by the degradation of methyl orange (MO) dye under UV light irradiation. Pure ZnO and Ni-doped ZnO thin films took 150 min and 100 min to degrade about 60% MO dye, respectively.

In the present paper, the theoretical investigation of the device structure ITO/CeO2/SnS/Spiro-OMeTAD/Mo of SnS-based solar cell has been performed. The aim of this work is to examine how the Spiro-OMeTAD HTL affects the performance of SnS-based heterostructure solar cell. Using SCAPS-1D simulation software, various parameters of SnS-based solar cell such as work function, series and shunt resistance and working temperature have been investigated. With the help of Spiro-OMeTAD, the suggested cell’s open-circuit voltage was increased to 344 mV. The use of Spiro-OMeTAD HTL in the SnS-based solar cell resulted in 14% efficiency increase, and the proposed heterojunction solar cell has 25.65% efficiency. The cell’s performance is determined by the carrier density and width of the CeO2 ETL (electron transport layer), SnS absorber layer and Spiro-OMeTAD HTL (hole transport layer). These data reveal that the Spiro-OMeTAD solar cells could have been a good HTL (hole transport layer) in regards to producing SnS-based heterojunction solar cell with high efficiency and reduced cost.

Implementing sensitive and fast ppb-level formaldehyde sensing at room temperature is still in extreme demand for practical indoor air quality monitoring. Herein, we developed a visible-light-sensitive and dipole-modified graphene-based nanocomposite ZnOx@ANS-rGO for ultrasensitive trace formaldehyde sensing. The rich oxygen vacancy zinc oxide (ZnOx) nanoparticles on graphene nanosheets provide OH-groups and edge sorption sites to facilitate the activation of adsorbed oxygen. Moreover, the supramolecular assembled 5-aminonaphthalene-1-sulfonic acid-modified graphene (ANS-rGO) nanosheets with donor–π–acceptor dipole served as an excellent conduction platform to transport and collect photo-generated electrons. Based on the collaboration of rich ZnOx and ANS-rGO, the obtained sensor ZnOx@ANS-rGO-0.1 showed the highest response (Ra/Rg = 1.58 to 1 ppm HCHO) among the MOS materials reported so far, and its limit of detection (LOD) can be as low as 5 ppb under 405 nm light illumination at RT. The outstanding efficiency and accuracy of the obtained gas sensor were confirmed by practical performance estimation in a 30 m3 chamber. The selectivity, long-term stability, repeatability and humidity resistance of the obtained sensors at RT were also revealed. The sensing mechanism based on the combination of visible-light activation and dipole modification was analyzed by the O-XPS, PL, in situ ATR-FTIR and charge density difference calculation.

Photocatalysts provide excellent potential for the full removal of organic chemical pollutants as an environmentally friendly technology. It has been noted that under UV-visible light irradiation, nanostructured semiconductor metal oxides photocatalysts can degrade different organic pollutants. The Sn6SiO8/rGO nanocomposite was synthesized by a hydrothermal method. The Sn6SiO8 nanoparticles hexagonal phase was confirmed by XRD and functional groups were analyzed by FT-IR spectroscopy. The bandgap of Sn6SiO8 nanoparticles (NPs) and Sn6SiO8/GO composites were found to be 2.7 eV and 2.5 eV, respectively. SEM images of samples showed that the flakes like morphology. This Sn6SiO8/rGO nanocomposite was testing for photocatalytic dye degradation of MG under visible light illumination and excellent response for the catalysts. The enhancement of photocatalytic performance was mainly attributed to the increased light absorption, charge separation efficiency and specific surface area, proved by UV-vis DRS. Further, the radical trapping experiments revealed that holes (h+) and superoxide radicals (·O−2) were the main active species for the degradation of MG, and a possible photocatalytic mechanism was discussed.

Herein, we report the facile synthesis, characterization and visible-light-driven photocatalytic degradation of perforated curly Zn0.1Ni0.9O nanosheets synthesized by hydrothermal process. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies confirmed the cubic phase crystalline structure and growth of high density perforated curly Zn0.1Ni0.9O nanosheets, respectively. As a photocatalyst, using methylene blue (MB) as model pollutant, the synthesized nanosheets demonstrated a high degradation efficiency of ~76% in 60 min under visible light irradiation. The observed results suggest that the synthesized Zn0.1Ni0.9O nanosheets are attractive photocatalysts for the degradation of toxic organic waste in the water under visible light.

This analysis aims to determine photon attenuation for five different ternary and binary iodide compounds using Phy-X/PSD software. For a broad range of photon energies between 0.015 and 15 MeV, the mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP) for the samples of Cu2HgI4, Ag2HgI4, CuI, AgI, and HgI were calculated. For illustration, the following values of TVL apply at 1 MeV: S1: 6.062 cm, S2: 6.209 cm, S3: 6.929 cm, S4: 6.897 cm, and S5: 4.568 cm. Some important parameters, such as total atomic cross-sections (ACS), electronic cross-sections (ECS), the effective atomic numbers (Zeff), effective electron density (Neff), and effective conductivity (Ceff) of the samples were also calculated. Additionally, exposure buildup factors (EBF) and energy-absorption buildup factor (EABF) were estimated. These data on the radiation characteristics of our samples could be useful for gamma attenuation. The HgI sample has the highest FNRCS values (0.0892) relative to the other tested samples showing good neutron attenuation features. The CuI sample shows low gamma attenuation features; in contrast, it shows high neutron attenuation features.

Implementing parts per billion-level nitric oxide (NO) sensing at room temperature (RT) is still in extreme demand for monitoring inflammatory respiratory diseases. Herein, we have prepared a kind of core-shell structural Hemin-based nanospheres (Abbr.: Hemin-nanospheres, defined as HNSs) with the core of amorphous Hemin and the shell of acetone-derived carbonized polymer, whose core-shell structure was verified by XPS with argon-ion etching. Then, the HNS-assembled reduced graphene oxide composite (defined as HNS-rGO) was prepared for RT NO sensing. The acetone-derived carbonized polymer shell not only assists the formation of amorphous Hemin core by disrupting their crystallization to release more Fe-N4 active sites, but provides protection to the core. Owing to the unique core-shell structure, the obtained HNS-rGO based sensor exhibited superior RT gas sensing properties toward NO, including a relatively higher response (Ra/Rg = 5.8, 20 ppm), a lower practical limit of detection (100 ppb), relatively reliable repeatability (over 6 cycles), excellent selectivity, and much higher long-term stability (less than a 5% decrease over 120 days). The sensing mechanism has also been proposed based on charge transfer theory. The superior gas sensing properties of HNS-rGO are ascribed to the more Fe-N4 active sites available under the amorphous state of the Hemin core and to the physical protection by the shell of acetone-derived carbonized polymer. This work presents a facile strategy of constructing a high-performance carbon-based core-shell nanostructure for gas sensing.

Herein, NOx, i.e., nitric oxide (NO) and nitrogen dioxide (NO2), gas sensors were fabricated using iron (Fe)-doped ZnO nanoparticles prepared via the facile hydrothermal process. The synthesized Fe-doped ZnO nanoparticles were analyzed through several techniques that revealed the well-crystallinity and dense growth of nanoparticles with the typical diameters of 25 ± 5 nm. The synthesized nanoparticles were utilized as a prospective material for the fabrication of NOx gas sensors operating at different temperatures, i.e., 350 °C, 400 °C, and 450 °C. The detailed sensing performances revealed that the optimum and most suitable sensing temperature for the fabricated sensors is 400 °C. In presence of 10 ppm NO gas, the fabricated sensor exhibited the highest gas response of 1.35 with a response (tresponse) and recovery (trecovery) time of 44 s and 402 s, respectively. Similarly, the fabricated NO2 gas sensor, in presence of 10 ppm gas shows the highest gas response of 1.33 with a response and recovery times of 50 s and 281 s, respectively. The presented results demonstrate that Fe-doped ZnO nanomaterials are capable to fabricate efficient NOx gas sensors.

Herein, we report the high-temperature electrical characteristics of heterojunction diode fabricated based on n-Ga-doped ZnO nanowires/p-Silicon substrate. Various electronic properties such as rectification ratio, the effective barrier height, the diode ideality factor, etc. of the fabricated heterojunction diode at high temperature were investigated. The electrical characteristics were examined in the high-temperature range of 293 K–433 K in both reverse and forward biased conditions, which exhibited good stability over the entire temperature range. The observed current–voltage (I–V) studies confirmed three different conduction mechanisms for the fabricated heterojunction diodes, i.e., either field emission or tunneling, recombination-tunneling mechanism and the transport mechanism dominated by space-charge-limited current at the different regions. The observed electrical results exhibited fluctuations in the sensitivity of the quality factor of the heterojunction diode and consequently corresponding fluctuations in the resistance. The linear dependence of effective barrier height on quality factor can be attributed to the presence of some lateral inhomogeneities in the barrier height. The analysis of C–V data was conducted to deduce the value of barrier height of Schottky barrier for the fabricated heterojunction diode. Interestingly, the observed results assert the mismatch that occurs between the interface states and resulting capacitance of the fabricated heterojunction diode.

Herein, we report the effect of synthesis temperature on the morphologies, optical and electronic properties of magnesium oxide (MgO) nanostructures. The MgO nanostructures were synthesized at different temperatures, i.e., 100 °C, 300 °C, and 600 °C by simple chemical reaction process and their morphology, particle size, optical, and electrical properties were examined by different techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and UV-Vis. spectroscopy. The morphological investigations revealed that various morphologies of MgO nanostructures, i.e., nanoparticles, nanosheet networks, and nanoneedles were synthesized at 100 °C, 300 °C, and 600 °C. The XRD results confirmed that with increasing the synthesis temperature, the crystallinity of the synthesized nanostructures increases. Further, the dielectric properties and AC conductivity at various frequencies for MgO nanostructures were studied which revealed that the dielectric losses decrease with increase in frequency and temperature. In addition, the observed band gap decreases from 4.89 eV to 4.438 eV (100 °C to 600 °C) representing its increase in the conductivity.

Herein, we report the facile microwave-assisted synthesis, characterization and photocatalytic degradation applications of Bismuth ferrite heterostructures composed of interconnected nanosheets (BHNs). The synthesized materials were subjected to several analytical studies such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy and UV-visible spectroscopy in order to examine the morphological, structural, optical and photo catalytic properties. The structural and morphological characterizations confirmed the rhombohedral perovskite crystal structure and the formation of heterostructures composed of interconnected nanosheets for the synthesized material. The compositional characterization revealed that the synthesized material is bismuth ferrite with high purity. The BHNs were further used as efficient photocatalyst for the photocatalytic degradation of highly hazardous pollutant methyl orange under sunlight irradiation. The sunlight driven photocatalytic experiments revealed ~86% photodegradation of methyl orange dye in 150 min. The presented work revealed that the synthesized BHNs are excellent material for the photocatalytic degradation of various organic contaminants and hazardous pollutants.

Herein, we report a simple synthesis, characterization and photocatalytic degradation application of composite NiO-WO₃ nanoparticles. The nanoparticles were synthesized by facile low-temperature method and characterized by several techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-Vis diffuse reflectance spectra (DRS). The synthesized NiO-WO₃ nanoparticles were used as efficient photocatalyst for the photocatalytic degradation of Eosin yellow (EY) dye. Interestingly, the synthesized photocatalytic exhibited a significant visible-light driven photocatalytic degradation of Eosin yellow (EY) dye. Under optimized conditions (pH = 5, catalyst dosage = 3 μM and initial dye concentration= 1.0 g/L), the obtained photo degradation of EY dye was above 95% in 180 min under visible light irradiation. Remarkably, reusability of the prepared photocatalyst was also observed and the photo-degradation reactions follow the pseudo-first-order model.

Herein, we report the facile synthesis of Iron oxide@Pt core-shell nanoparticles (NPs) by facile two step synthesis process. The first step follows the growth of iron oxide nanoparticle by thermal decomposition process while the second step deals with the formation of iron oxide@Pt core-shell nanoparticles by the chemical reduction method. The synthesized core-shell nanoparticles were characterized by several techniques and used for the catalytic reductive translation of Cr(VI) to Cr(III) in the presence of formic acid by a UV-vis spectrophotometer. The UV photo-spectrometer analysis confirmed the conversion efficiency from 12% to as high as 98.8% at the end of 30 minutes. Thus, the presence of Iron oxide @Pt core-shell nanoparticles (NPs) can be effectively used as a catalyst for the reducion of Cr(VI) to Cr(III) ions. Additionally, antibacterial studies were performed for the prepared core-shell nanoparticles against two bacterial strains, i.e., gram (+ve) Staphylococcus Aureus (S. Aureus) and gram (-ve) Escherichia Coli (E. Coli).

In this paper, the heterojunction diode based on n-Ga doped ZnO nanowires interconnected with disks/p-Si assembly was fabricated and their low-temperature electrical properties were examined. The Ga-doped ZnO nanowires interconnected with disks were grown over p-Si substrate and studied by numerous techniques to understand the structural, compositional and morphological characteristics. Electrical properties, at lowtemperatures ranging from 77 K–295 K, were examined for the fabricated heterojunction diode assembly both in reverse and forward biased conditions which exhibited an excellent stability over all the temperature range. The detailed electrical characterizations revealed that the current decreases gradually from 1.9 μA, to 0.87 μA to 0.84 μA when temperature increases from 77 K, 100 K to 150 K and then increases gradually from 1.86 μA–3.36 μA and to 9.95 μA when temperature increases from 200 K–250 K and to 295 K, respectively. Both the highest rectifying ratio at 100 K and the lowest one at 295 K occur in the voltage range of 2–5 V.

Heterojunction diode based on n-ZnO nanorods/p-Silicon (Si) assembly was fabricated, examined and reported here. Horizontal quartz tube thermal evaporation technique was used for the growth of ZnO nanorods on Si substrate. The nanorods were characterized by several techniques to examine the structural, morphological, scattering and electrical properties. Wurtzite hexagonal phase of the grown aligned nanorods was observed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The appearance of a sharp Raman peak at 438 cm–1 was observed and it is related to the E2(high) mode of the wurtzite hexagonal phase of ZnO. The electrical properties of the fabricated heterojunction assembly were examined at different temperatures (298∼398 K) in both reverse and forward biased conditions, and a good stability was observed over the entire temperature range. A reduction in the turn-on and breakdown voltage was observed with increasing temperature. By increasing the temperature, the effective potential barrier height was increased, while quality factor was decreased. The observed activation energy was found to be ∼93.4 meV, higher than the exciton binding energy of ZnO.

Carbon dioxide (CO2), an important gas molecule metabolite produced by the tricarboxylic acid cycle, is a direct signal for identifying cancers in cells and tissues. Herein, design and synthesis of a novel "breathable" block polymer supramolecular assembly probe consisting of a hydrophilic block, an amidine-containing CO2-responsive block, and an aggregation-induced emission (AIE) luminescence block to detect CO2 metabolized by cancer cells is reported. The triblock copolymer poly-(4-undecoxy tetraphenyl ethylene methacrylate)-b-poly-((N-amidino)-(2,3-dihydro-1H-1, 4-methyl-1, 2,3-triazole)-(ethenylbenzene))-b-poly(ethylene oxide) (PTPE-b-PAD-b-PEO) was successfully synthesized and characterized. This triblock copolymer could be self-assembled into "breathable" aqueous solution vesicles. In the presence of CO2, the amidine-containing CO2-responsive block (PAD block) of the vesicle "inhales" an amount of CO2, which causes the volume of the vesicle to expand. The expansion of the vesicle induces the aggregation of the AIE luminescence block (PTPE block), which resulted in the fluorescence intensity enhancement. The supramolecular vesicles "exhale" CO2, and the volume and AIE phenomenon of the vesicles decrease when N2 is passed into the solution. On the basis of this reversible change of fluorescence intensity, HeLa cervical cancer cells, CNE1 nasopharynx cancer cells, 5-8F nasopharynx cancer cells, 16HBE human bronchial epithelial cells, and GES-1 human gastric mucosa epithelial cells have all been successfully detected and identified.

Special functional groups to modify the surface of graphene have received much attention since they enable the charge transfer enhancement, thus realizing gas-sensing at room temperature. In this work, three typical redox dye molecules, methylene blue (MB), indigo carmine (IC) and anthraquinone-2-sulfonate (AQS), were selected to be supramolecularly assembled with reduced graphene oxide (rGO), respectively. Remarkably, three graphene-based materials AQS-rGO (response = 3.2, response time = 400 s), IC-rGO (response = 4.3, response time = 300 s) and MB-rGO (response = 7.1, response time = 100 s) exhibited excellent sensitivity and short response time toward 10 ppm NO2 at room temperature. The corresponding NO2 sensing mechanism of the obtained materials was further investigated by cyclic voltammetry (CV) measurements. CV was conducted to measure the anodic peak potential (Epa) of three redox dyes. Interestingly, it is obvious that the Epa values were positively correlated with the gas sensitivity and response time of the three materials. To explore the mechanism, UV–vis spectroscopy was adopted to analyze the lowest unoccupied molecular orbitals (LUMOs) of three redox dye molecules. The results show that the oxidation abilities of three redox dyes were also positively correlated with the gas sensitivity and response time of three corresponding graphene-based materials.

A low-cost and simple drop-casting method was used to fabricate a carbon nanodot (C-dot)/all-inorganic perovskite (CsPbBr3) nanosheet bilayer heterojunction photodetector on a SiO2/Si substrate. The C-dot/perovskite bilayer heterojunction photodetector shows a high performance with a responsivity (R) of 1.09 A/W, almost five times higher than that of a CsPbBr3-based photodetector (0.21 A/W). In addition, the hybrid photodetector exhibits a fast response speed of 1.318/1.342 µs and a highly stable photocurrent of 6.97 µA at 10 V bias voltage. These figures of merits are comparable with, or much better than, most reported perovskite heterojunction photodetectors. UV–Vis absorption and photoluminescent spectra measurements reveal that the C-dot/perovskite bilayer heterojunction has a band gap similar to the pure perovskite layer, confirming that the absorption and emission in the bilayer heterojunction is dominated by the top layer of the perovskite. Moreover, the emission intensity of the C-dot/perovskite bilayer heterojunction is less than that of the pure perovskite layer, indicating that a significant number of charges were extracted by the C-dot layer. The studied band alignment of the C-dots and perovskites in the dark and under emission reveals that the photodetector has a highly efficient charge separation mechanism at the C-dot/perovskite interface, where the recombination rate between photogenerated electrons and holes is significantly reduced. This highly efficient charge separation mechanism is the main reason behind the enhanced performance of the C-dot/perovskite bilayer heterojunction photodetector.

This study reports the biosynthesis of silver nanoparticles (AgNPs) using methanolic leaf extract of Pogostemon cablin Benth. (Patchouli) as a reducing agent, and their potent biological (antibacterial, antioxidant and anticancer) activities. The P. cablin extract when exposed to silver nitrate reduced silver ions to form crystalline AgNPs within 1 h of incubation at room-temperature. UV-visible spectra showed a sharp surface plasmon resonance (SPR) at around 430 nm for the biosynthesized AgNPs and the XRD pattern indicated the crystalline planes of the face centered cubic silver. The FE-SEM analysis revealed the occurrence of predominant spherical shaped AgNPs with a huge disparity in their particle size distribution with an average size of 25 nm, while, the FTIR data confirmed the bio-reduction and capping of AgNPs by several phytocompounds present in the methanolic leaf extract. AgNPs effectively inhibited the growth of all the tested human pathogenic bacterial strains (Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli), while, the methanolic leaf extract failed to inhibit the growth of S. aureus and P. aeruginosa. AgNPs showed the highest free radical scavenging activity (79.0 ± 0.76%) compared to methanolic leaf extract (68.3 ± 0.68%) at 100 μg/ml. Further, the cytotoxicity study using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) confirmed that AgNPs successfully inhibited the human colon adenocarcinoma cell line (HT-29) in a dose dependent manner. At higher concentrations (500 μg/ml), only 4% of cells survived after 72 hrs of exposure with IC50 value of 120 μg/ml. Thus, these findings offer a new source of biomolecules with diverse biological activities.