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Bio‐based flexible dielectric substrates have gained tremendous attention for their potential to reduce environmental risks from nonbiodegradable electronic waste. The present study demonstrates the fabrication of facile, nontoxic, and biodegradable chitosan‐based flexible dielectric substrate using graphene nanoplatelet (GNP) as a nanofiller. The detailed impact of different concentrations of GNP (1, 2, and 3 wt%) into the chitosan (CS) matrix was studied on physicochemical, morphological, mechanical, electrical, and thermal properties. The fabricated CS/GNP composites showed improved mechanical strength, thermal stability, and electrical properties compared with unmodified CS film. The composites exhibited excellent thermal stability (200°C) with a promising biodegradation rate (within 6 days). The mechanical strength of the unmodified CS film was increased unequivocally with 2 wt% GNP loading with tensile strength of 23.56 Mpa. Furthermore, the current–voltage (I–V) characteristic curves for CS/GNP (2%) and CS/GNP (3%) showed similar current conduction and ohmic behavior in flat, bending, and flat‐after‐bending modes. The dielectric measurements revealed that the CS/GNP composite with 2 wt% filler exhibited optimal performance having permittivity (έ) of 32.71 (at 102 Hz) with low dielectric loss of 0.04 (at 106 Hz). These results suggest that the dielectric films offer strong prospects as an eco‐friendly alternative for various applications. Highlights: Biodegradable chitosan‐based flexible dielectric films were prepared.Films were made using a simple solvent casting method with 1–3 wt% GNP filler.Optimum physicochemical and electrical properties were seen at 2 wt% GNP.CS/GNP (2%) film exhibited ohmic behavior in both flat and bending modes.Excellent dielectric properties were achieved at 2 wt% GNP filler. [ABSTRACT FROM AUTHOR]

Herein, we synthesized guanidine functionalized graphene oxide nanocomposites referred to GO‐GN NCs using hummer's method. GO‐GN NCs was characterized using Fourier‐Transform Infrared Spectroscopy, Powder X‐ray Diffraction, Thermogravimetric Analysis, Raman Spectroscopy, Field Emission Scanning Electron Microscopy, Transmission Electron Microscopy, Brunauer‐Emmett‐Teller (BET) surface area analysis to confirm successful formation of GO‐GN NCs catalysts. The catalytic performance for GO‐GN NCs was evaluated for Knoevenagel and Aldol condensation reaction in aqueous medium at ambient condition and result shows that it could be used as a highly efficient, stable, and durable catalyst. In addition, it has another feature such as easy workup procedure, large substrate tolerance, high reaction yield, good recyclability, and environmental friendliness. [ABSTRACT FROM AUTHOR]

Semiconductor colloidal quantum dots (CQDs) have emerged as pivotal entities at the forefront of modern nanotechnology, promising revolutionary advancements across various fields including optoelectronics, quantum computing, photocatalysis, and biomedical imaging. In this comprehensive review, we present the latest developments in CQD research offering a profound exploration of their innovative concepts and analyzing recent methodologies and strategies across diverse domains. We first explore the superiority of CQDs over other nanomaterials in the biomedical, optoelectronics, analytical sensing, and photocatalysis domains along with the discovery of CQDs with modern developments. We begin with photophysical properties of CQDs that include size-tunable bandgaps, narrow linewidth emissions, tunable surface chemistry and charge transport, excitation-dependent photoluminescence quantum yields, fluorescence blinking, and "dark fractions". We even address the origin of blinking along with models that govern the fluorescence intermittency within the nanocrystal followed by how the photoluminescence quantum yield (PLQY) of CQDs is hampered by excitation energy and "dark fractions". Then, we delve into the development of exemplary devices featuring a spectrum of architectures, elucidating the recent progress that has led to significant improvements in optoelectronic device efficiency. Furthermore, we examine procedures for converting CQDs into adaptable biological probes for subcellular imaging, drug delivery vehicles, biosensors, and therapeutic agents in the biomedical domain. Additionally, we thoroughly investigate the critical role of ligand selection and synthesis protocols in photocatalysis and analytical sensing, elucidating the underlying photophysical principles in each application. We also discuss ongoing debates, future directions, and emerging trends in the field, aiming to spark increased interest in CQDs and CQD-based composites by showcasing their myriad advantages across various applications. This review serves to underscore the transformative potential of CQDs and stimulate further exploration and innovation in harnessing their unique capabilities. [ABSTRACT FROM AUTHOR]

The metal intoxication and its associated adverse effects to humans have led to the research for development of water treatment technologies from pollution hazards. Therefore, development of cheaper water remediation technologies is more urgent than ever. Clays and clay minerals are naturally occurring, inexpensive, non-toxic materials possessing interesting chemical and physical properties. As a result of interesting surface properties, these have been developed as efficient absorbent in water remediation. Recently, clay–polymer nanocomposites have provided a cost-effective technological platform for removing contaminants from water. Covering research advancements from past 25 years, this review highlights the developments in clay–polymer nanocomposites and their advanced technical applications are evaluated with respect to the background and issues in remediation of toxic metals and organic compounds from water. The extensive analysis of literature survey of more than two decades suggests that future work need to highlight on advancement of green and cost-effective technologies. The development of understanding of the interaction and exchange between toxin and clay–polymer composites would provide new assembly methods of nanocomposites with functional molecules or nanomaterials need to be extended to increase the detection and extraction limit to parts per trillion. [ABSTRACT FROM AUTHOR]

Hydrogels, polymer networks with versatile applications in both energy-related devices and biomedicine, fall into three categories: natural, synthetic, and hybrid hydrogels. Natural variants like alginate and collagen boast biocompatibility, while synthetic counterparts, such as polyacrylamide, offer customizable properties. Hybrid hydrogels seamlessly combine the strengths of both. With their distinctive features, including high water content, flexibility, and porosity, hydrogels prove well-suited for applications in energy storage devices and biomedicine. In the energy sector, hydrogels serve as electrolytes, separators, and electrodes, enhancing battery performance and enabling the functionality of supercapacitors and fuel cells. This review initiates by exploring the pivotal role of hydrogels as energy storage devices, particularly in batteries and supercapacitors. It delves into the design principles and fabrication techniques utilized to augment the electrochemical performance, durability, and safety of hydrogel-based energy storage systems. The examination extends to various hydrogel types, such as PAMPS, PAA, and PEO hydrogels, assessing their suitability for high-performance batteries and flexible supercapacitors. Additionally, this review scrutinizes the burgeoning biomedical technologies where hydrogels play a crucial role, emphasizing their contributions to tissue engineering, drug delivery systems, biosensors, and wound healing. The unique attributes of hydrogels, including biocompatibility, adaptable mechanical properties, and controlled release capabilities, position them favorably for diverse biomedical applications. The discussion highlights notable hydrogel systems, such as alginate-based, PEGDA, and PVA hydrogels, in the context of these advancements in biomedicine. [ABSTRACT FROM AUTHOR]

The present work describes the synthesis of a material consisting of a bisimidazolium ionic liquid supported on graphene oxide. The prepared nanocomposite was characterized by different physicochemical techniques such as FT-IR, XRD, CHN, SEM, TEM and EDAX. The synthesized nanocomposite was further utilized as an effective heterogeneous catalyst for the synthesis of tetraketone derivatives, which are biologically significant, using dimedone and aryl aldehydes as the substrates at 50 °C and a green solvent. One of the tetraketone products has been confirmed by single crystal XRD. The catalyst displayed high reaction yields, facile separation, short reaction time, good stability and recoverability up to six consecutive reaction rounds with no discernible loss in its catalytic activity. [ABSTRACT FROM AUTHOR]

The solution-phase fabrication of photovoltaic cells has drawn a wide attention in the area of flexible electronics owing to their cost-effective and easy fabrication methodology. In addition to the different other layers, the transparent conducting layers have demonstrated a very important role in the fabrication of various flexible devices such as display panel, organic light-emitting diodes, and transparent heater. The most commonly used material for transparent electrodes (TEs) are indium tin oxide (ITO), aluminium zinc oxides (AZO), which required highly expensive vacuum-based harsh deposition methods. To reduce the overall fabrication cost of the thin film solar cells, researcher have devoted great efforts to replace the expensive ITO/AZO by applying silver nanowire (AgNW) or copper nanowire (CuNW)-based nanocomposite as TEs in photovoltaic cells. The emphasis is given on the deposition techniques so that the nanowire-based composite electrode can be deliberately prepared by surface engineering for desired applications. The utilization of AgNW or CuNW-based nanocomposite prepared by different methods of deposition have been explored in the field of photovoltaics as TE. The exhaustive analysis on the deposition methods to prepare nanowire-based TE will benefit the researcher to further achieve new advancement in the field of flexible electronics. [ABSTRACT FROM AUTHOR]

This study aimed to identify suitable sites for tea cultivation using both random forest and logistic regression models. The study utilized 2770 sample points to map the tea plantation suitability zones (TPSZs), considering 12 important conditioning factors, such as temperature, rainfall, elevation, slope, soil depth, soil drainability, soil electrical conductivity, base saturation, soil texture, soil pH, the normalized difference vegetation index (NDVI), and land use land cover (LULC). The data were normalized using ArcGIS 10.2 and the models were calibrated using 70% of the total data, while the remaining 30% of the data were used for validation. The final TPSZ map was classified into four different categories: highly suitable zones, moderately suitable zones, marginally suitable zones, and not-suitable zones. The study revealed that the random forest (RF) model was more precise than the logistic regression model, with areas under the curve (AUCs) of 85.2% and 83.3%, respectively. The results indicated that well-drained soil with a pH range between 5.6 and 6.0 is ideal for tea farming, highlighting the importance of climate and soil properties in tea cultivation. Furthermore, the study emphasized the need to balance economic and environmental considerations when considering tea plantation expansion. The findings of this study provide important insights into tea cultivation site selection and can aid tea farmers, policymakers, and other stakeholders in making informed decisions regarding tea plantation expansion. [ABSTRACT FROM AUTHOR]

Organic compounds containing heteroatoms have been comprehended to exhibit a remarkable tendency towards corrosion mitigation. This corrosion mitigating tendency is enabled by the presence of electron clouds composed of lone pairs, pi-electrons, which allow them to be adsorbed over metallic equivalents. Because of the availability of nitrogen as heteroatoms, these compounds are being extensively used for corrosion diminution. This article looks at a variety of heterocyclic organic compounds like imidazole, triazole, pyridine, pyrazole, quinoline, tetrazole, pyrimidine, purine and pyrrole, having nitrogen as their prime constituent heteroatom for their anti-corrosive properties. The anti-corrosive properties of these nitrogen-based compounds in acidic conditions have been demonstrated using all available experimental techniques such as EIS, PDP and other theoretical investigations such as DFT and MD. Furthermore, the shift in the trend of these compounds inhibitory efficiencies has been noted and underlined here. [ABSTRACT FROM AUTHOR]

Cancer is a cluster of diseases, which caused by the mutation in cells and it has the potential to cover any part of the body. The whole world is vigorously struggling to find a safe approach to cure the cancer. The classical chemotherapy approach involves the use of chemotherapeutic agents to kill cancer cells. The major disadvantage of therapy is less in vivo stability and negatively affects the healthy cells. Nowadays, the targeted drug delivery techniques has gained lots of interest, because of the efficient drug release at the cancerous sites. Herein, we have synthesized Folic acid (FA) coated and Doxorubicin drug (Dox) encapsulated mesoporous silica nanocomposites (FA/Dox@Silica)for targeted delivery of DOX and bioimaging. Encapsulation of Dox was done to make it more stable in the cell atmosphere and for its controlled release. The coating of FA makes these nanocomposites makes them an vehical for chemically targeted delivey of DOX, as it was already confirmed by several studies that there are folate receptors present over cancer cells and these reseptors are responsive towards the FA Thus these nanocomposites can be easily recognized by the cancer cells and they can efficiently deliver drugs. The shape, size, morphology, crystallinity, porosity, and fictionalizations were analyzed by using several characterization techniques such as DLS, TEM, and FTIR. The drug loading was confirmed qualitatively by using optical spectroscopic techniques. The drug release pattern was studiedfor the 15 days which showed the sustained and regulated release of drug from the mesoporous silica nanocomposites. Cellular uptake was observed by cell staining assay confirmed the fair uptake of nanoparticles. [ABSTRACT FROM AUTHOR]

A series of facial-Re(CO)3-based acyclic complexes (1–3) possessing N∩O bis-chelating ligands and a triphenylphosphine oxide donor was synthesized and characterized. The most interesting structural feature of these complexes is that both the coordinated ligands are functionalized with external phenyl rings. Single crystal X-ray diffraction analysis confirms that each molecule demonstrates a variety of intermolecular supramolecular interactions via the external phenyl rings. All the complexes displayed strong absorption (ε = 14 000–40 000 M−1 cm−1) over wide visible region (400–600 nm). Due to the interesting structural and photophysical properties of the complexes, a satisfactory DNA binding ability was observed. The binding of the complexes with DNA grooves was confirmed by a significant increase in the absorption intensities of the complexes in the visible region, absorption enhancement of DNA and circular dichroism. [ABSTRACT FROM AUTHOR]

In this work, the shape effect of silver nanoparticles (AgNPs) on photocatalysis and electrical conductivity was investigated. Different shapes of AgNPs achieved using various concentrations of NaBH4 were characterized using particle size analysis, UV–visible spectroscopy and high‐resolution transmission electron microscopy. The colours of colloidal solutions were found to be influenced by the shape of the nanoparticles. Yellow and blue AgNPs were spherical and triangular in shape, respectively, whereas distorted spherical particles showed a red colour and the presence of both particles in one solution resulted in a green colloidal solution. The AgNPs were used to prepare Ag/poly(vinyl alcohol) (PVA) composite films and their electrical conductivity was investigated. Owing to their better charge carrier generation, uniform distribution in the PVA matrix and enhanced surface plasmon resonance, blue AgNPs (triangular shaped) exhibited superior conductivity performance compared to the other nanoparticles. The values for maximum conductivity for the blue and yellow AgNPs were 3.45 × 10−4 Ω−1 cm−1 and 2.67 × 10−4 Ω−1 cm−1respectively. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

We report a robust synthesis of polymeric plasticiser from the post-consumer plastic waste, i.e. poly(ethylene terephthalate) (PET) and its subsequent use as plasticiser for preparation of nitrile rubber (NBR) and nitrile-PVC rubber blends. PET waste was depolymerised by alcoholysis with the help of 1-decanol. The obtained oligomeric plasticiser was characterised for its chemical structure using Fourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance. The prepared polymeric plasticiser was then used for the preparation of nitrile and nitrile-PVC blend rubber sheets. NBR and nitrile-PVC blend rubber sheets were also prepared by using dioctyl phthalate as plasticiser. The fabricated sheets were compared for their mechanical properties such as tensile strength, elongation at break, hardness. The effect of ageing on mechanical properties was also analysed. It was observed that the use of polymeric plasticiser resulted in significant improvement in tensile properties and ageing resistance. This eco-friendly synthesis of plasticiser offers its use for high-performance applications. [ABSTRACT FROM AUTHOR]