Black aluminum is a material characterized by high surface porosity due to columnar growth and exhibits unique optical properties that make it attractive for applications such as light trapping, infrared detection, and passive thermal radiation cooling. In this study, we correlate the structural and optical properties of black aluminum by comparing it with conventional reflective aluminum layers. These layers of varying thicknesses were deposited on fused silica substrates, and their optical properties were analyzed.
View Article and Find Full Text PDFAs an atomically thin electric conductor with a low density of highly mobile charge carriers, graphene is a suitable transducer for molecular adsorption. In this study, we demonstrate that the adsorption properties can be significantly enhanced with a laser-deposited TiO nanolayer on top of single-layer CVD graphene, whereas the effective charge transfer between the TiO-adsorbed gas molecules and graphene is retained through the interface. The formation of such a heterostructure with optimally a monolayer thick oxide combined with ultraviolet irradiation (wavelength 365 nm, intensity <1 mW/mm) dramatically enhances the gas-sensing properties.
View Article and Find Full Text PDFPlant resource sharing mediated by mycorrhizal fungi has been a subject of recent debate, largely owing to the limitations of previously used isotopic tracking methods. Although CdSe/ZnS quantum dots (QDs) have been successfully used for in situ tracking of essential nutrients in plant-fungal systems, the Cd-containing QDs, due to the intrinsic toxic nature of Cd, are not a viable system for larger-scale in situ studies. We synthesized amino acid-based carbon quantum dots (CQDs; average hydrodynamic size 6 ± 3 nm, zeta potential -19 ± 12 mV) and compared their toxicity and uptake with commercial CdSe/ZnS QDs that we conjugated with the amino acid cysteine (Cys) (average hydrodynamic size 308 ± 150 nm, zeta potential -65 ± 4 mV) using yeast as a proxy for mycorrhizal fungi.
View Article and Find Full Text PDFFluorescent nanoparticles (FNPs) have been widely used in chemistry and medicine for decades, but their employment in biology is relatively recent. Past reviews on FNPs have focused on chemical, physical or medical uses, making the extrapolation to biological applications difficult. In biology, FNPs have largely been used for biosensing and molecular tracking.
View Article and Find Full Text PDFNanomaterials (Basel)
October 2020
In this manuscript, we explore the sensor properties of epitaxially grown graphene on silicon carbide decorated with nanolayers of CuO, FeO, VO, or ZrO. The sensor devices were investigated in regard to their response towards NH as a typical reducing gas and CO, CH, CHO, and NO as gases of interest for air quality monitoring. Moreover, the impact of operating temperature, relative humidity, and additional UV irradiation as changes in the sensing environment have been explored towards their impact on sensing properties.
View Article and Find Full Text PDFGraphene in its pristine form has demonstrated a gas detection ability in an inert carrier gas. For practical use in ambient atmosphere, its sensor properties should be enhanced with functionalisation by defects and dopants, or by decoration with nanophases of metals or/and metal oxides. Excellent sensor behaviour was found for two types of single layer graphenes: grown by chemical vapour deposition (CVD) and transferred onto oxidized silicon (Si/SiO₂/CVDG), and the epitaxial graphene grown on SiC (SiC/EG).
View Article and Find Full Text PDFWe present, to the best of our knowledge, a new method for differential temperature measurement based on thermal sensitivity of the fluorescence lifetime of thermographic phosphors. Pairs of thermographic phosphors are excited with intensity-modulated light at frequencies ω and ω+Δω. The phase shift Δθ of the summary fluorescence intensity beat signal envelope is measured.
View Article and Find Full Text PDFBeilstein J Nanotechnol
March 2017
Graphene has been recognized as a promising gas sensing material. The response of graphene-based sensors can be radically improved by introducing defects in graphene using, for example, metal or metal oxide nanoparticles. We have functionalised CVD grown, single-layer graphene by applying pulsed laser deposition (PLD) of VO which resulted in a thin VO layer on graphene with average thickness of ≈0.
View Article and Find Full Text PDFAn enhanced Raman scattering from a thin layer of adenine molecules deposited on graphene substrate was detected. The value of enhancement depends on the photon energy of the exciting light. The benzene ring in the structure of adenine molecule suggests π-stacking of adenine molecule on top of graphene.
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