Multi-colored, water soluble fluorescent carbon nanodots (C-Dots) with quantum yield changing from 4.6 to 18.3% were synthesized in multi-gram using dated cola beverage through a simple thermal synthesis method and implemented as conductive and ion donating supercapacitor component. Various properties of C-Dots, including size, crystal structure, morphology and surface properties along with their Raman and electron paramagnetic resonance spectra were analyzed and compared by means of their fluorescence and electronic properties. α-Manganese Oxide-Polypyrrole (PPy) nanorods decorated with C-Dots were further conducted as anode materials in a supercapacitor. Reduced graphene oxide was used as cathode along with the dicationic bis-imidazolium based ionic liquid in order to enhance the charge transfer and wetting capacity of electrode surfaces. For this purpose, we used octyl-bis(3-methylimidazolium)diiodide (C8H16BImI) synthesized by N-alkylation reaction as liquid ionic membrane electrolyte. Paramagnetic resonance and impedance spectroscopy have been undertaken in order to understand the origin of the performance of hybrid capacitor in more depth. In particular, we obtained high capacitance value (C = 17.3 μF/cm2) which is exceptionally related not only the quality of synthesis but also the choice of electrode and electrolyte materials. Moreover, each component used in the construction of the hybrid supercapacitor is also played a key role to achieve high capacitance value.

Numerous methods have been reported for the preparation of liposomes, many of which, in addition to requiring time-consuming preparative steps and the use of organic solvents, result in heterogeneous liposome populations of incontrollable size. Taking into consideration the phenomenon of spontaneous vesiculation and the theory of curvature, here we present an extremely rapid and simple, solvent-free method for the preparation of monodisperse solutions of highly stable small unilamellar vesicles using both charged and zwitterionic lipids mixed with lyso-palmitoylphosphatidylcholine, exploiting a combination of a rapid pH change followed by a defined period of equilibration. Various experimental parameters and their interactions were evaluated in terms of their effect on resulting liposome size and shape, as well as on liposome stability and size distribution, with transmission electron microscope imaging being used to visualize the formed liposomes, and photon correlation spectroscopy to obtain statistical data on mean diameter and monodispersity of the liposome population. zeta potential measurements also provided information about the interpretation of vesiculation kinetics and liposome stability. The time interval of pH jump, operation temperature, equilibration time, and lipid type were shown to be the determining factors controlling the size, shape, and monodispersity of the liposomes. Buffer type was also found to be important for the long-term storage of the liposomes. Ongoing work is looking at the application of the developed method for encapsulation of bioactive molecules, such as drugs, genetic materials, and enzymes.

A robust supercapacitor device consisting of a 3D nanoassembly of conductive polymers fostered with Mn2+ and carbon dots has been fabricated.

An amyloid-like peptide molecule self-assembling into one-dimensional nanofiber structure in ethanol was designed and synthesized with functional groups that can bind to gold ions. The peptide nanofibers were used as templates for nucleation and growth of one-dimensional gold nanostructures in the presence of ascorbic acid as reducing agent. We performed multistep seed-mediated synthesis of gold nanoparticles by changing peptide/gold precursor and peptide/ reducing agent ratios. Gold nanostructures with a wide range of morphologies such as smooth nanowires, noodle-like onedimensional nanostructures, and uniform aggregates of spherical nanoparticles were synthesized by use of an environmentally friendly synthesis method. Nanoscale electrical properties of gold-peptide nanofibers were investigated using atomic force microscopy. Bias dependent current (IV) measurements on thin films of gold-peptide nanofiber hybrid revealed tunneling dominated transport and resistive switching. Gold-peptide nanofiber composite nanostructures can provide insight into electrical conduction in biomolecular/inorganic composites, highlighting their potential applications in electronics and optics.

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Herein, we reported the synthesis of solvatochromic, red fluorescence-emitting carbon dots (rCDs) from para-phenylenediamine (p-PD) by a one-step microwave-assisted solvothermal method. The effect of surface passivation with hydroxyl-enriched HBPs of varying generation numbers (G2 and G4) on the optical, physicochemical, and solvatochromic properties of the rCDs was evaluated. The quantum yield (QY) of rCDs was altered from 31.4% to 79.8% in EtOH when their surface was passivated with HBP-G4 (rCD-bis64); however, surface passivation of rCDs with HPBs did not alter the solvatochromic property of rCDs, where only a slight decay was observed in rCD-bis64. The solvatochromism of rCDs with a red-shifted fluorescence emission from green to red as a response to increased solvent polarity was used as a simple and economical quantitative analysis tool for naked-eye, fluorometric, and smartphone-applicable on-site detection of moisture in organic solvents by converting the digital images to RGB. The polarity-dependent fluorescence color switchability of rCDs and rCDs-bis64 was then applied for the visual analysis of surface characteristics of paper strips. The visual response of both CDs to the changing paper type was transformed to a color map of the paper surface that was further used for visual and quantitative analyses of surface properties of the filter papers.

A bioinspired peptide amphiphile nanofiber template for formation of one-dimensional Pd nanostructures is demonstrated. The Pd and peptide nanocatalyst system enabled efficient catalytic activity in Suzuki coupling reactions in water at room temperature. The nanocatalyst system can be easily separated and reused in successive reactions without significant loss in activity and structural integrity.