Today, the development of nanomaterials with sensing properties attracts much scientific interest because of the demand for low-cost nontoxic colloidal nanoprobes with high sensitivity and selectivity for various biomedical and environment-related applications. Carbon dots (CDs) are promising candidates for these applications as they demonstrate unique optical properties with intense emissions, biocompatibility, and ease of fabrication. Herein, we developed synthesis protocols to obtain CDs based on o-phenylenediamine with a variety of optical responses depending on additional precursors and changes in the reaction media. The obtained CDs are N-doped (N,S-doped in case of thiourea addition) less than 10 nm spherical particles with emissions observed in the 300–600 nm spectral region depending on their chemical composition. These CDs may act simultaneously as absorptive/fluorescent sensing probes for solvent polarity with ∆S/∆ENT  up to 85, for ∆ENT from 0.099 to 1.0 and for pH values in the range of 3.0–8.0, thus opening an opportunity to check the pH in non-pure water or a mixture of solvents. Moreover, CDs preserve their optical properties when embedded in cellulose strips that can be used as sensing probes for fast and easy pH checks. We believe that the resulting dual-purpose sensing nano probes based on CDs will have high demand in various sensing applications.

Chemically synthesized carbon dots (CDs) have attracted a lot of attention as an eco-friendly and cost-efficient light-emitting material, and functionalization of CD surface with additives of different nature is a...

3D anisotropic semiconductor nanostructures have unique physical properties including a high aspect ratio, optical polarization anisotropy, polarized photoluminescence, giant birefringence, and many others. Theoretical studies of anisotropic semiconductor nanostructures have shown that their electronic and optical properties dramatically depend on their shape and size. These factors open up an access to new generation of optical, optoelectronic, and light‐harvesting devices. In this article, we demonstrate advances in the development of new 3D quantum‐confined colloidal nanostructures such as semiconductor nanotetrapods, nanomultipods, nanoflowers, nanostar and other shapes. We present the latest progress in various colloidal chemistry approaches for the synthesis of these nanostructures. We also consider the self‐organization of quantum dots in 3D superparticles. We discuss structure–property relations as well as the corresponding potential applications of these nanomaterials in light‐harvesting, energy‐conversion devices, sensing, photocatalysis, biology, and other areas. Finally, we provide conclusions and an outlook for the future development of anisotropic semiconductor nanomaterials and their technological prospects.

The project of organizing mineral-and-energy clusters with spatial conjugation of deposits of solid minerals (SM) and hydrocarbons (HC) localized on the continental margin and shelf of the Arctic zone of the Russian Federation is substantiated. Four clusters of the kind are characterized, i.e.: Murmansk-Barents, YamalNorilsk, Lena-Laptev Sea and Northeast-Chukotka, with the corresponding characteristics of the SM and HC resource bases, as well as substantiation of the bedrock gold and porphyry copper prospective areas in the Northeast-Chukotka cluster.An example of prediction and localization of the HC accumulations in the deep-water part of the Arctic Basin outside the 200-mile zone of the Russian shelf is considered. Geological and morphostructural evidence of the epicontinental nature of the bottom of the Amerasian and Eurasian basins is presented as a criterion for substantiating Russia's right to expand the outer boundary of the continental shelf.

On-going development of carbon dots (CDs) for different applications calls for search of novel methods for their synthesis and surface functionalization. For fabrication of light-emitting devices (LEDs), CDs should be soluble in non-polar solvents that are used for ink-printing of their functional layers, apart from the obvious requirement of bright luminescence. Herein, we introduce amphiphilic CDs synthesized from a mixture of benzoic acid and ethylenediamine in acetylacetone, which satisfy both above mentioned requirements. These CDs are quasi-spherical nanoparticles 20-50 nm in size, holding aliphatic, carbonyl, amide, imine, and carbamate groups at the surface which renders them amphiphilic and soluble in a variety of substances with relative polarity ranging from 0.002 to 1, such as toluene, chloroform, alcohols, and water. By variation of the molar ratio of benzoic acid and ethylenediamine, an optimal value for photoluminescence quantum yield of 36 % in non-polar solvents is achieved. Importantly, these CDs are easily mixable with a charge transport polymer – polyvinylcarbazole, a common component of organic LEDs. As a demonstration of use of developed amphiphilic CDs in LEDs, green emitting charge-injection devices are fabricated with a broad emission band centered at 515 nm, maximal luminance of 1716 cd/m2, and ССT of 5627 K.