The electrochemical sensor has received considerable attention because of the future on-time monitoring technologies. To meet the requirements of on-time monitoring applications, it is of prodigious importance to discover new catalysts for the electrochemical sensor that have good conductivity and physicochemical properties. The novelty of this work is the successful synthesis of lanthanum vanadate/functionalized boron nitride (LaV/F-BN) nanocomposites and their application toward the electrochemical detection of furazolidone (FZD). The fabricated sensors containing nanocomposites of LaV/F-BN modified electrode displayed improved electrochemical sensing behavior for the detection of FZD compared to other electrodes. This electrocatalyst showed reduction potential at −0.42 V (vs Ag/AgCl2), a low detection limit (0.003 μM), acceptable selectivity, and wide linear range (0.015–300 μM) with a correlation coefficient of 0.995, which is better than the previous literature. The enhanced catalytic activity of the proposed sensor is mainly attributed to the abundant exposed active sites, high surface area, better conductivity, rapid electron transfer, synergistic effect, and functional groups. The practical utility of the LaV/F-BN based sensor was evaluated via the determination of FZD in human blood serum and urine samples.

In the present study, a facile environmentally friendly approach was described to prepare monodisperse iron oxide (Fe3O4) nanoparticles (IONPs) by low temperature solution route. The synthesized nanoparticles were characterized using x-ray diffraction spectroscopy (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM) measurements, Fourier-Transform Infrared Spectroscopy (FTIR), and Thermogravimetric analysis (TGA) analyses. XRD patterns revealed high crystalline quality of the nanoparticles. SEM micrographs showed the monodispersed IONPs with size ranging from 6 to 9 nm. Synthesized nanoparticles demonstrated MICs of 32, 64, and 128 μg/ml against Gram negative bacteria i.e., Serratia marcescens, Escherichia coli, and Pseudomonas aeruginosa, respectively, and 32 μg/ml against Gram positive bacteria Listeria monocytogenes. IOPNs at its respective sub-MICs demonstrated significant reduction of alginate and exopolysaccharide production and subsequently demonstrated broad-spectrum inhibition of biofilm ranging from 16 to 88% in the test bacteria. Biofilm reduction was also examined using SEM and Confocal Laser Scanning Microscopy (CLSM). Interaction of IONPs with bacterial cells generated ROS contributing to reduced biofilm formation. The present study for the first time report that these IONPs were effective in obliterating pre-formed biofilms. Thus, it is envisaged that these nanoparticles with broad-spectrum biofilm inhibitory property could be exploited in the food industry as well as in medical settings to curtail biofilm based infections and losses.

Real-time monitoring of neurotransmitter levels is of tremendous technological demand, which requires more sensitive and selective sensors over a dynamic concentration range. As a use case, we report yttrium vanadate within three-dimensional graphene aerogel (YVO/GA) as a novel electrocatalyst for detecting dopamine (DA). This synergy effect endows YVO/GA nanocomposite with good electrochemical behaviors for DA detection compared to other electrodes. Benefiting from tailorable properties, it provides a large specific surface area, rapid electron transfer, more active sites, good catalytic activity, synergic effect, and high conductivity. The essential analytical parameters were estimated from the calibration plot, such as a limit of detection (1.5 nM) and sensitivity (7.1 μA μM–1 cm–2) with the YVO/GA sensor probe electrochemical approach. The calibration curve was fitted with the correlation coefficient of 0.994 in the DA concentration range from 0.009 to 83 μM, which is denoted as the linear working range. We further demonstrate the proposed YVO/GA sensor’s applicability to detect DA in human serum sample with an acceptable recovery range. Our results imply that the developed sensor could be applied to the early analysis of dementia, psychiatric, and neurodegenerative disorders.

With lithium-ion (li-ion) batteries as energy storage devices, operational safety from thermal runaway remains a major obstacle especially for applications in harsh environments such as in the oil industry. In this approach, a facile method via microwave irradiation technique (MWI) was followed to prepare co 3 o 4 /reduced graphene oxide (RGO)/hexagonal boron nitride (h-BN) nanocomposites as anodes for high temperature li-ion batteries. Results showed that the addition of h-BN not only enhanced the thermal stability of Co 3 o 4 /RGO nanocomposites but also enhanced the specific surface area. co 3 o 4 /RGO/h-BN nanocomposites displayed the highest specific surface area of 191 m 2 /g evidencing the synergistic effects between RGO and h-BN. Moreover, Co 3 o 4 /RGO/h-BN also displayed the highest specific capacity with stable reversibility on the high performance after 100 cycles and lower internal resistance. Interestingly, this novel nanocomposite exhibits outstanding high temperature performances with excellent cycling stability (100% capacity retention) and a decreased internal resistance at 150 °C. Li-ion batteries energy storage devices are used as a power source for almost all electronic devices due to the superior benefits over other types of batteries 1-4. However, the safety feature and the narrow temperature operating range of li-ion batteries remain a major obstacle for more complex applications of li-ion batteries such as in the oil industry, defense, automotive applications and aerospace that demand safe operation at wide temperature range (up to 150 °C). Li-ion batteries are known to operate effectively between −20 °C and 60 °C 5. With the increasing demand for li-ion batteries, many research has been made on increasing its thermal stability and the upper operating temperature range. When considering safety issues of li-ion batteries it is mainly related to thermal runaway. Conditions such as elevated temperature and high charge levels or overcharging abuses one or more of the battery components that results in what is called a short circuit leading to heat, fire or explosion. A process referred to as thermal runaway 6. Thermal runaway mechanisms occur mainly at the electrodes and electrolytes. Thermal decomposition of the electrodes or electrolytes and reduction or oxidation of the electrolyte is the main cause of thermal runaways. To solve this issue, many preventative measures have been investigated. Preventative measures can be the use of safety devices, that is, design devices that release high pressure and heat before thermal runaway but this is for engineers to set up new safe li-ion battery devices. However, what concerns scientists more is the inherent safety from electrodes, to electrolytes 7. Compromising between the electrochemical performances and thermal stability is a challenge.

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In this research work, SnO2, NiO and SnO2/NiO nanocomposites were synthesized at low temperature by modified sol–gel method using ultrasonication. Prepared samples were investigated for their properties employing various characterization techniques. X-ray diffraction (XRD) patterns confirmed the purity and phase of the samples as no secondary phase was detected. The average crystallite size of the nanocomposites was found to decrease from 19.24 to 4.53 nm with the increase in NiO concentration. It was confirmed from SEM micrographs that the material has mesoporous morphology. This mesoporous morphology resulted in the increase of the surface to mass ratio of the material, which in turn increases the specific capacitance of the material. The UV–Visible spectra showed the variation in the band gap of SnO2/NiO at different weight ratio ranging from 3.49 to 3.25 eV on increasing NiO concentration in the samples. These composites with different mass ratio of SnO2 and NiO were also characterized by FT-IR spectroscopy that showed shifting of the peaks centered at 545 cm−1 in the spectra for NiO/SnO2 nanocomposite. The analysis of the electrochemical performance of the material was done with the help of cyclic voltammetry and Galvanostatic charge–discharge. The specific capacitance of the synthesized samples with different concentration of SnO2 and NiO was analyzed at different scan rates of 5 to 100 mV/s. Interestingly, 7:1 mass ratio of NiO and SnO2 (SN7) nanocomposite exhibited a maximum specific capacitance of ~ 464 F/g at a scan rate of 5 mV/s and good capacitance retention of 87.24% after 1,000 cycles. These excellent electrochemical properties suggest that the SnO2/NiO nanocomposite can be used for high energy density supercapacitor electrode material.

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