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Poor electrical conductivities, structural instabilities and long synthesis procedures, limit the application of metal organic frameworks (MOFs) in energy storage systems. In the present work, we synthesize a cobalt‐benzene tricarboxylic acid based MOF (CoBTC MOF) via two different approaches i. e. solvothermal route and mechanochemical grinding for its utility in energy storage. When characterized structurally and electrochemically, the CoBTC MOF synthesized by mechanochemical method is found to be superior because of large surface area, enhanced porosity/diffusion process through MOF and structural robustness along with less time requirement. Further, its hybrid composite with graphene nanosheets (CoBTC MOF/GNS) was prepared for its performance as a supercapacitor material. The characterization reveals the formation of sandwich structure where CoBTC MOF rods (thickness ranging from 0.5 to 2 μm) are placed in between GNS. This arrangement has resulted into high specific capacitance of 608.2 F.g−1 at current density of 0.25 A.g−1 in 1 M KOH electrolyte along with excellent capacitance retention up to 94.9% after 2000 charge/discharge cycles. Also, a symmetric supercapacitor has been assembled for practical application of CoBTC MOF/GNS which demonstrates specific capacitance of 183.2 F.g−1 with high energy density and power density of 49.8 Wh.kg−1 and 1025.8 W.kg−1 respectively, along with 92.1% retention of initial capacitance after 5000 charge‐discharge cycles.

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Background: Electroanalytical techniques play a very important role in the areas of medicinal, clinical as well as pharmaceutical research. Amongst these techniques, the voltammetric methods for the determination of drugs using nanomaterials based chemically modified electrodes (CMEs) have received enormous attention in recent years. This is due to the sensitivity and selectivity they provide on qualitative as well as quantitative aspects of the electroactive analyte under study. The aim of the present review was to discuss the work on nanomaterials based CMEs for the analysis of drugs covering the period from 2000 to present employing various voltammetric techniques for different classes of the drugs. Methods: The present review deals with the determination of different classes of drugs including analgesics, anthelmentic, anti-TB, cardiovascular, antipsychotics and anti-allergic, antibiotic and gastrointestinal drugs. Also, a special section is devoted for enantioanalysis of certain chiral drugs using voltammetry. The detailed information of the voltammetric determination for the drugs from each class employing various techniques such as differential pulse voltammetry, cyclic voltammetry, linear sweep voltammetry, square wave voltammetry, stripping voltammetry, etc. are presented in tabular form below the description of each class in the review. Results: Various nanomaterials including carbon nanotubes, graphene, carbon nanofibers, quantum dots, metal/metal oxide nanoparticles, polymer based nanocomposites have been used by researchers for the development of CMEs over a period of time. The large surface area to volume ratio, high conductivity, electrocatalytic activity and biocompatibility make them ideal modifiers where they produce synergistic effect which helps in trace level determination of pharmaceutical, biomedical and medicinal compounds. In addition, macrocyclic compounds as chiral selectors have been used for the determination of enantiomeric drugs where one of the isomers captured in the cavities of chiral selector shows stronger binding interaction for one of the enantiomorphs. Conclusion: arious kinds of functional nanocomposites have led to the manipulation of peak potential due to drug - nanoparticles interaction at the modified electrode surface. This has facilitated the simultaneous determination of drugs with almost similar peak potentials. Also, it leads to the enhancement in voltammetric response of the analytes. It is expected that such modified electrodes can be easily miniaturized and used as portable, wearable and user friendly devices. This will pave a way for in-vivo onsite real monitoring of single as well as multi component pharmaceutical compounds.

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Herein, a novel nanostructure hybrid electrode based on silicon carbide supports a bismuth‐cobalt‐zinc ternary oxide composite (SiC/BiCoZnO) material that is designed for a high‐performance supercapattery device. The hybrid microstructure SiC/BiCoZnO is synthesized by a simple hydrothermal method subsequently followed by a calcination process. The mesoporous BiCoZnO nanoparticles (with specific surface area of 154.5 m2 g−1) are linked on the large surface of SiC structures in a SiC/BiCoZnO nanocomposite. The hybrid electrode possesses a high specific capacity of 841.1 C g−1 at a current density of 1 A g−1 in a mixed electrolyte of 1 m KOH + 1 m Na2SO4 due to synergistic effects of high conduction as well as large SiC structures and redox active metals present in the BiCoZnO nanoparticles. Moreover, the SiC/BiCoZnO nanocomposite displays excellent rate performance in a symmetric supercapattery device, which offers an excellent energy density of 76.25 Wh kg−1 at 1 A g−1 and maximum power output of 19 000 W kg−1 at 20 A g−1 with an outstanding capacity retention of 84.2% after 10 000 charge–discharge cycles. Thus, the hybrid architecture of the SiC/BiCoZnO nanocomposite with superior electrochemical properties can make it highly beneficial for the fabrication of energy and power devices.

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Synthesis process of Fe3O4/Ag nanocomposite followed by its fabrication as an electrochemical sensor for determination of DcCl using adsorptive stripping square wave voltammetry.