In this study, electrochemical oxidation of methanol to formic acid using the economical and highly active catalytic Nickel Benzene tricarboxylic acid metal organic framework (Ni-BTC-MOF) and reduced graphene oxide (rGO) nanocomposites modified glassy carbon electrode GCE in alkaline media, which was examined via cyclic voltammetry technique. Nickel based MOF and rGO nanocomposites were prepared by solvothermal approach, followed by morphological and structural characterization of prepared samples through X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and energy dispersive X-ray (EDX) analysis. The electrochemical testing of synthesized materials represents the effect of the sequential increase in rGO concentration on electrocatalytic activity. The Ni-BTC/4 wt % rGO composite with a pronounced current density of 200.22 mA/cm² at 0.69 V versus Hg/HgO electrode at 50 mV/s was found to be a potential candidate for methanol oxidation in Direct Methanol Fuel Cell (DMFC) applications. Product analysis was carried out through Gas Chromatography (GC) and Nuclear Magnetic Resonance (NMR) spectroscopy, which confirmed the formation of formic acid during the oxidation process, with approximately 62% yield.

In this work a novel bimetallic nickel oxide/copper oxide metal–organic framework (NiO/CuO MOF) has been developed by using two linkers: Benzene Dicarboxylic acid (BDC) and Pyrazine. The composites of NiO/CuO MOF with different amounts of reduced graphene oxide (rGO) were synthesized through a hydrothermal method and subsequently characterized by multiple significant techniques like XRD, SEM, EDX, FTIR and Raman IR for an investigation of their structural and morphological properties. The prepared series of material was later employed for electrochemical oxidation of methanol, tested by cyclic voltammetry (CV) in basic medium on a modified glassy carbon electrode (GCE). The electrochemical response depicts that increasing concentration of rGO enhances the electrocatalytic activity of the catalyst for methanol oxidation reaction (MOR). The catalyzed oxidation reaction of methanol by NiO/CuO MOF and rGO-NiO/CuO MOF composites give a superlative current density of 437. 28 mA/cm² at 0.9 V potential at 50 mV/s scan rate. This activity makes it a promising catalytic material for electrolysis of methanol in direct methanol fuel cell (DMFC).

The objective of the present study was to achieve the successful encapsulation of a therapeutic agent to achieve antifouling functionality regarding biomedical applications. Considering nanotechnology, drug-loaded polycaprolactone (PCL)-based nanoparticles were prepared using a nano-precipitation technique by optimizing various process parameters. The resultant nano-formulations were investigated for in vitro drug release and antifouling applications. The prepared particles were characterized in terms of surface morphology and surface properties. Optimized blank and drug-loaded nanoparticles had an average size of 200 nm and 216 nm, respectively, with associated charges of −16.8 mV and −11.2 mV. Studies of the in vitro release of drug were carried out, which showed sustained release at two different pH, 5.5 and 7.4 Antifouling activity was observed against two bacterial strains, Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. The zone of inhibition of the optimized polymeric drug-loaded nanoparticle F-25 against both strains were compared with the pure drug. The gradual pH-responsive release of antibiotics from the biodegradable polymeric nanoparticles could significantly increase the efficiency and pharmacokinetics of the drug as compared to the pure drug. The acquired data significantly noted that the resultant nano-encapsulation of antifouling functionality could be a promising candidate for topical drug delivery systems and skin applications.

Solar energy conversion through photoelectrochemical water splitting (PEC) is an upcoming promising technique. MoS₂/CoTe heterostructures were successfully prepared and utilized for PEC studies. MoS₂ and CoTe were prepared by a hydrothermal method which were then ultrasonicated with wt. % ratios of 1:3, 1:1 and 3:1 to prepare MoS₂/CoTe (1:3), MoS₂/CoTe (1:1) and MoS₂/CoTe (3:1) heterostructure, respectively. The pure materials and heterostructures were characterized by XRD, UV–vis-DRS, SEM, XPS, PL and Raman spectroscopy. Photoelectrochemical measurements were carried out by linear sweep voltammetry and electrochemical impedance spectroscopic measurements. A maximum photocurrent density of 2.791 mA/cm² was observed for the MoS₂/CoTe (1:1) heterojunction which is about 11 times higher than the pristine MoS₂. This current density was obtained at an applied bias of 0.62 V vs. Ag/AgCl (1.23 V vs. RHE) under the light intensity of 100 mW/cm² of AM 1.5G illumination. The enhanced photocurrent density may be attributed to the efficient electron–hole pair separation. The solar to hydrogen conversion efficiency was found to be 0.84% for 1:1 MoS₂/CoTe, signifying the efficient formation of the p-n junction. This study offers a novel heterojunction photocatalyst, for PEC water splitting.

Methyl orange (MO) is mutagenic, poisonous, and carcinogenic in nature, hence, effective methods are required for its degradation. We have synthesized pure ZrO₂, Ag-doped ZrO_2, and Ag-doped ZrO₂/rGO as hybrid photocatalysts by facile hydrothermal method. These photocatalysts were characterized by powder XRD, scanning electron microscopy, EDX, FTIR, photoluminescence, UV–Vis diffuse reflectance (DRS), and Raman spectroscopy. The photodegradation of MO (10 ppm) was studied with pure ZrO₂, Ag-doped ZrO_2, and Ag-doped ZrO₂/rGO (10 mg/100 mL catalyst dosage) photocatalysts at 100 min irradiation time under UV–Visible light. The pH effect and catalyst dosage on photodegradation of MO was investigated. Ag_0.04ZrO₂/rGO photocatalyst exhibited the maximum photocatalytic degradation of MO (87%) as compared to Ag_0.04ZrO₂ (60%) and pure ZrO₂ (26%). Reusability experiments ensured the excellent stability of photocatalyst after five consecutive experiments. To the best of our knowledge, this is the first report on the facile hydrothermal synthesis of Ag_0.04ZrO₂/rGO photocatalyst for photocatalytic degradation of methyl orange.