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The development of advanced materials for energy storage and gas sensing applications has gained significant attention in recent years. In this study, we synthesized and characterized PANI@MnO 2 @rGO ternary nanocomposites (NCs) to explore their potential in supercapacitors and gas sensing devices. The ternary NCs were synthesized through a multi-step process involving the hydrothermal synthesis of MnO 2 nanoparticles, preparation of PANI@rGO composites and the assembly to the ternary PANI@MnO 2 @rGO ternary NCs. The structural, morphological, and compositional characteristics of the materials were thoroughly analyzed using techniques such as XRD, FESEM, TEM, FTIR, and Raman spectroscopy. In the realm of gas sensing, the ternary NCs exhibited excellent performance as NH 3 gas sensors. The optimized operating temperature of 100 °C yielded a peak response of 15.56 towards 50 ppm NH 3 . The nanocomposites demonstrated fast response and recovery times of 6 s and 10 s, respectively, and displayed remarkable selectivity for NH 3 gas over other tested gases. For supercapacitor applications, the electrochemical performance of the ternary NCs was evaluated using cyclic voltammetry and galvanostatic charge-discharge techniques. The composites exhibited pseudocapacitive behavior, with the capacitance reaching up to 185 F/g at 1 A/g and excellent capacitance retention of approximately 88.54% over 4000 charge-discharge cycles. The unique combination of rGO, PANI, and MnO 2 nanoparticles in these ternary NCs offer synergistic advantages, showcasing their potential to address challenges in energy storage and gas sensing technologies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Using gold (Au) nanoparticle decorated Ti 3 C 2 T x (Ti 3 C 2 T x -Au) nanocomposites, a highly sensitive electrochemical aptasensor for the effective detection of chloramphenicol has been developed. As a two-dimensional layered material, the prepared composite not only provides high surface area, good conductivity, and thermal stability but also substantial binding sites for aptamers with high sensitivity and selectivity for the accurate determination of chloramphenicol. Interestingly, the conductivity and active sites were enhanced by freeze-drying Ti 3 C 2 T x and in situ formation of Ti 3 C 2 T x -Au nanocomposite. The fabricated aptasensor exhibited a very low detection limit (S/N ≥ 3) of 13.18 fg mL -1 with a linear range of 1 ~ 700 pg mL -1 and correlation coefficient of 0.9992. The fabricated aptasensor demonstrated an excellent reproducibility, repeatability, long-term stability, and high selectivity toward chloramphenicol. Further, the aptasensor was applied to real milk samples, and the recoveries were ranged from 98.93 to 101.93%., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Mechanically-robust nanocomposite membranes have been developed via crosslinking chemistry and electrospinning technique based on the rational selection of dispersed phase materials with high Young's modulus (i.e., graphene and multiwalled carbon nanotubes) and Cassie-Baxter design and used for oil and water separation. Proper selection of dispersed phase materials can enhance the stiffness of nanocomposite fiber membranes while their length has to be larger than their critical length. Chemical modification of the dispersed phase materials with fluorochemcials and their induced roughness were critical to achieve superhydrophobocity. Surface analytic tools including goniometer, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, atomic force microscopy (AFM) and scanning electron microscope (SEM) were applied to characterize the superhydrophobic nanocomposite membranes. An AFM-based nanoindentation technique was used to measure quantitativly the stiffness of the nanocomposite membranes for local region and whole composites, compared with the results by a tensile test technique. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques were used to confirm composition and formation of nanocomposite membranes. These membranes demonstrated excellent oil/water separation. This work has potential application in the field of water purification and remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Herein, we report the synthesis and characterizations of Vanadium pentoxide (V 2 O 5 ) nanorods/graphene oxide (GO) nanocomposite as efficient direct solar light driven photocatalyst for the enhanced degradation of victoria blue (VB) dye. The nanocomposite was synthesized by sonochemical process and characterized using several analytical methods in order to study the structural, morphological, compositional, optical and photocatalytic properties. The X-ray diffraction studies confirmed the orthorhombic structure of V 2 O 5 while the morphological examinations revealed the growth of V 2 O 5 nanorods and 2D GO sheets. Interestingly, the UV studies ratify that the bandgap of the nanocomposite was reduced compared to pure GO and V 2 O 5 . Interestingly, the interaction of the V 2 O 5 nanorods with the graphene oxide substrate and its effect on the electronic properties of the combined system, have been examined by means of theoretical calculations, based on the so called Geometry, Frequency, Noncovalent, eXtended Tight Binding (GFN-xTB) method. Studying the photocatalytic behavior of nanocomposite, we observe an almost complete degradation (97.95%) of Victoria Blue (VB) dye under direct sunlight illumination within just 90 min. The outstanding nanocomposite photocatalytic efficiency was due to the excellent transfer of interfacial charge and the suppressed recombination of charge-carrier. The kinetics of the degradation process was also analyzed by calculating the rate constant and half-life time. Finally, a possible mechanism has also been discussed for the degradation process of VB dye using nanocomposite under direct sunlight irradiation., (Copyright © 2021 Elsevier Inc. All rights reserved.)

CdO-ZnO nanocomposites were synthesized using a simple solution approach, and several characterization approaches were used to examine the morphological, structural, phase, vibrational, optical, and compositional properties of these CdO-ZnO nanocomposites. The FESEM study revealed the development of aggregates ranging in size from 250 nm to 500 nm. These aggregates were composed of various CdO-ZnO nanoparticle shapes and sizes. XRD investigation revealed hexagonal wurtzite and cubic phases in ZnO and CdO, respectively. The crystal size was 28.06 nm. The band-gap energy of the produced nanocomposites was calculated using UV-Vis analysis and was determined to be 2.55 eV. The CdO-ZnO nanocomposites were employed as a promising material for the effective fluorescence detection of hydrazine and for the quicker photocatalytic degradation of Rhodamine B (RhB) dye. Within 120 min of UV light exposure, the RhB dye was 87.0% degraded in the presence of the CdO-ZnO nanocomposites and the degradation process followed zero-order and pseudo-first-order kinetics. Based on 3σ IUPAC criteria, the limit of detection for fluorescent hydrazine sensing was 28.01 µM. According to the results presented here, CdO-ZnO nanocomposites may function as both a photocatalyst for the breakdown of organic pollutants as well as an effective luminous sensor for the detection of harmful analytes. [ABSTRACT FROM AUTHOR]

This study introduces a facile synthesis method for synthesizing reduced graphene oxide (rGO) nanosheets with surface decoration of polyaniline (PANI). The resultant rGO@PANI nanocomposite (NC) exhibit substantial potential as advanced electrode materials for high-performance supercapacitors. The strategic integration of PANI onto the rGO surface serves dual purposes, effectively mitigating agglomeration of rGO films and augmenting their utility in supercapacitor applications. The PANI coating manifests a highly porous and nanosized morphology, fostering increased surface area and optimized mass transport by reducing diffusion kinetics. The nanosized structure of PANI contributes to the maximization of active sites, thereby bolstering the efficacy of the nanocomposites for diverse applications. The inherent conductive nature of the rGO surface significantly expedites electron transport, thereby amplifying the overall electrochemical performance of the nanocomposites. To systematically evaluate the influence of PANI concentration on the electrode performance, varying concentrations of PANI were incorporated. Notably, an elevated PANI concentration was found to enhance the response owing to the unique morphology of PANI. Remarkably, the 5 % rGO@PANI NC emerged as the most promising candidate, demonstrating exceptional response characteristics with a specific capacitance of 314.2 F/g at a current density of 1 A/g. Furthermore, this catalyst exhibits outstanding long-term stability, retaining approximately 92 % of its capacitance even after enduring 4000 cycles. This research underscores the significance of the synergistic integration of rGO and PANI in the design of high-performance supercapacitors. The elucidation of the underlying mechanisms governing the improved electrochemical properties contributes to the fundamental understanding of nanocomposite behavior, thereby paving the way for the rational design of next-generation energy storage materials. [ABSTRACT FROM AUTHOR]

Waterborne epoxy (WEP) nanocomposite coating with hydrothermal synthesized zinc oxide (ZnO)-reduced graphene oxide (RGO)- polypyrrole (PPy) was prepared and an enhanced corrosion resistance was reported. Experiment results showed that WEP nanocomposite coating with Z8R2P (the mass ratio of ZnO-RGO-PPy of 8:2:1) exhibited the highest value of the impedance at the lowest frequency (such as |Z| 0.01Hz), the lowest corrosion current density and the largest value of charge transfer resistance (R ct). Even after 94 days of immersion, the |Z| 0.01Hz value of Z8R2P/WEP nanocomposite coating was 4.45 × 103 Ω·cm2, pointing out that Z8R2P/WEP coating possessed the long superior anticorrosion performance. Moreover, salt spray experiments with a period of 50 days showed that Z8R2P/WEP coating had the best integrity of coating compared with other coatings, revealing that Z8R2P/WEP coating had the best corrosion protection performance. The characterization and analysis of phase composition and corrosion morphology revealed that the synergistic protection mechanism of Z8R2P/WEP coating was attributed to barrier effects of RGO, chemical passivation of ZnO and accept the released electrons of PPy. • This is the first report of hydrothermal synthesis of ZnO-RGO-PPy for anticorrosion application. • A small amount of ZnO-RGO-PPy significantly improved anticorrosion performance of epoxy coating. • The mechanism for the enhanced anticorrosion of the epoxy nanocomposite coatings was disclosed. [ABSTRACT FROM AUTHOR]