A5020270160- Graphene research and applications
- Diamond and Carbon-based Materials Research
- Carbon Nanotubes in Composites
- Graphene and Nanomaterials Applications
- Advancements in Battery Materials
- Supercapacitor Materials and Fabrication
- ZnO doping and properties
- Metal and Thin Film Mechanics
- Carbon and Quantum Dots Applications
- Conducting polymers and applications
- Chalcogenide Semiconductor Thin Films
- 2D Materials and Applications
- Gas Sensing Nanomaterials and Sensors
- High-pressure geophysics and materials
- Electrocatalysts for Energy Conversion
- MXene and MAX Phase Materials
- Copper-based nanomaterials and applications
- Quantum Dots Synthesis And Properties
- Semiconductor materials and devices
- Nanocluster Synthesis and Applications
- Advanced Memory and Neural Computing
- Fuel Cells and Related Materials
- Electronic and Structural Properties of Oxides
- Transition Metal Oxide Nanomaterials
- Advanced biosensing and bioanalysis techniques
University of South Africa
2015-2024
Siksha O Anusandhan University
2024
Tamkang University
2007-2024
Institute of Technical Education
2024
Pioneer (United States)
2015-2023
University of the Witwatersrand
2010-2019
University of Pretoria
2018
Institute of Materials Research of the Slovak Academy of Sciences
2011
Indian Association for the Cultivation of Science
1991-2009
Consejo Superior de Investigaciones Científicas
2005
Fluorescent carbon nanoparticles (CNPs) 2−6 nm in size with a quantum yield of about ∼3% were synthesized via nitric acid oxidation soot, and this approach can be used for milligram-scale synthesis these water-soluble particles. These CNPs are nanocrystalline predominantly graphitic structure show green fluorescence under UV exposure. Nitric induces nitrogen oxygen incorporation into soot particles, which afforded water solubility light-emitting property; the isolation small particles from...
Fluorescent nanoparticle-based imaging probes have advanced current labelling technology and are expected to generate new medical diagnostic tools based on their superior brightness photostability compared with conventional molecular probes. Although significant progress has been made in fluorescent semiconductor nanocrystal-based biological imaging, the presence of heavy metals toxicity issues associated severely limited application potential these nanocrystals. Here, we report a carbon...
Electronic structures of graphene oxide (GO) and hydro-thermally reduced oxides (rGOs) processed at low temperatures (120–180°C) were studied using X-ray absorption near-edge structure (XANES), emission spectroscopy (XES) resonant inelastic scattering (RIXS). C K-edge XANES spectra rGOs reveal that thermal reduction restores = sp2 bonds removes some the oxygen hydroxyl groups GO, which initiates evolution carbonaceous species. The combination Kα XES shows overlapping π π* orbitals in GO are...
Grain boundaries in bulk perovskite films are considered as giant trapping sites for photo-generated carriers. Surface engineering <italic>via</italic> inorganic quantum dots has been employed creating monolithically grained, pin-hole free films.
The rational approach motivated the design of novel antimicrobial silver and silver–copper bimetallic nanoparticles contained within zeolitic imidazolate framework-8 supported on graphene oxide (GO), Ag@ZIF-8@GO, AgCu@ZIF8@GO. In resultant composites, ZIF-8 was able to prevent stacking GO sheets also acted as a carrier for its cavities. GO, other hand, an anchoring support enabling uniform dispersion nanocomposites, thus eliminating their aggregation. morphological physicochemical properties...
O K-, Au, Ag, and Pt L3-edge X-ray absorption near-edge structure (XANES), emission spectroscopy, scanning photoelectron microscopy (SPEM) measurements have been performed to study the correlation between electronic structures photocatalytic activities of nanocrystalline (nc)-(Au, Pt) particles on surface ZnO nanorods (ZnO-NRs). The K-edge XANES spectra reveal greater occupation 2p orbitals, i.e., a negative effective charge ions, in nc-Pt/ZnO-NRs than nc-(Au, Ag)/ZnO-NRs. This result...
Water soluble graphene with various chemical- and biofunctionalities is essential for their different applications. However, exfoliated graphenes are insoluble in water oxide precipitate if they chemically reduced to graphene. We have developed a polyacrylate coating method then it into found that can improve the colloidal stability of both oxide. The coated has been characterized using XPS, FTIR, XRD micro-Raman spectroscopy. primary amine present on backbone used derive glucose...
We report an investigation into the magnetic and electronic properties of partially hydrogenated vertically aligned few layers graphene (FLG) synthesized by microwave plasma enhanced chemical vapor deposition. The FLG samples are at different substrate temperatures to alter degree hydrogenation their depth profile. unique morphology structure gives rise a geometry in which graphane/graphone is supported bulk, very from other widely studied structures such as one-dimensional nanoribbons....
This study investigates the strong photoluminescence (PL) and X-ray excited optical luminescence observed in nitrogen-functionalized 2D graphene nanoflakes (GNFs:N), which arise from significantly enhanced density of states region π gap between π* states. The increase number sp2 clusters form pyridine-like N-C, graphite-N-like, C=O bonding resonant energy transfer N O atoms to were found be responsible for blue shift enhancement main PL emission feature. is strongly related induced changes...
Abstract Nitrogen-doped graphene oxides (GO:N x ) were synthesized by a partial reduction of oxide (GO) using urea [CO(NH 2 ]. Their electronic/bonding structures investigated X-ray absorption near-edge structure (XANES), valence-band photoemission spectroscopy (VB-PES), emission (XES) and resonant inelastic scattering (RIXS). During GO:N synthesis, different nitrogen-bonding species, such as pyrrolic/graphitic-nitrogen, formed replacing oxygen-containing functional groups. At lower...
Various synchrotron radiation-based spectroscopic and microscopic techniques are used to elucidate the room-temperature ferromagnetism of carbon-doped ZnO-nanowires (ZnO-C:NW) via a mild C+ ion implantation method. The photoluminescence magnetic hysteresis loops reveal that C reduces number intrinsic surface defects increases saturated magnetization ZnO-NW. interstitial implanted ions constitute majority in ZnO-C:NW as confirmed by X-ray absorption studies. circular dichroism spectra O...
Synthesizing co-amorphous system is one of the most promising approaches to enhance solubility, and dissolution rate pharmaceuticals improve their oral bioavailability. Here, we screen eleven co-formers to...
Abstract Fluorescent gold clusters (FGCs) with tunable emission from blue to red and quantum yields in the range of 6–17 % have been synthesized by simple modification conditions used for synthesis nanoparticles, namely replacing stronger reducing agent a controlled amount thiol. Various functional FGCs hydrodynamic diameters 5–12 nm successfully as cell labels. The results our investigations strongly indicate that composed Au 0 are more stable imaging probes than commonly reported...