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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]

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]