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Triethanolamine is a widely used model electron donor that enables a fast screening of the photocatalyst parameters in both, homogeneous and heterogeneous scenarios. We report a new role of triethanolamine in heterogeneous photoregeneration of cofactor molecules – nicotinamide adenine dinucleotide (NADH) – using state-of-the-art heterogeneous photocatalysts. In contrast to the common model involving the light-induced electrons and holes generation to reduce the substrate and oxidize triethanolamine simultaneously, we identified glycolaldehyde as a stable product of triethanolamine degradation capable of reducing NAD+. Triethanolamine, apart from playing a role of a precursor for reducing agent, maintains the alkalinity of the solution to drive the reduction. Our findings offer a fresh insight into the triethanolamine-assisted photocatalysis because glycolaldehyde as such have generally been neglected in mechanistic considerations. Moreover, a spatial and temporal decoupling of the photocatalyst from the substrate reduction reaction minimizes the product re-oxidation, thus implying a relevant feature for the real-world applications using a continuous flow setting., F. V. would like to thank ScotChem for the financial support. Y. R. would like to thank The Ministry of Education and Science of the Russian Federation (grant no. 14.Y26.31.0011).

Strong exciton–plasmon interaction enables effective control of the photonic properties of hybrid organic–inorganic nanostructures encompassing light absorption, scattering and luminescence. Whereas the manifestations of light-matter interactions in the absorption and scattering are reasonably well understood their relation to the luminescence as well as luminescence properties themselves in strongly coupled plexcitonic hybrids is still largely underexplored especially for a system with a complex mechanism of hybridisation of states. Here we report on investigation of the interaction between localized and hybridized plasmons in gold nanostars and excitons in J-aggregates under ambient conditions. Our findings demonstrate the quality performance of the formed plexciton system with multiple hybridization channels in terms of the parameters of strong coupling, such as Rabi splitting (230 meV), coupling-strength-to-transition energy ratio (0.07), and cooperativity (2.03). The results of time-resolved experiments elucidate the observed enhanced spontaneous emission rate with regard to the Purcell effect, whose value was estimated from the extinction spectra of the strongly coupled plexciton system., Financial supports from Projects PID2019-111772RB-I00 of the Spanish MINECO and the Ministry of Science and Higher Education of the Russian Federation (Grant No. 14.Y26.31.0011) are acknowledged. Y. R. acknowledges the support from the Basque Government (grant no. IT1164-19). P.S. and I.N acknowledge support from the Russian Science Foundation (grant no. 21-79-30048) of the part of this work related to nanomaterials manufacturing and functionalisation. I.N. acknowledges support from the Université de Reims Champagne-Ardenne. A.S.-I. acknowledges the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720).

The optical properties of diamond spherical-like particles, prepared by the hot-filament chemical vapor deposition technique on opal substrates, have been investigated. The particles were studied using scanning electron microscopy, micro-Raman spectroscopy and micro-photoluminescence techniques. The diamond particles, consisting of polycrystalline diamond, have a size of about 5 μm. Periodic peaks in the background of the photoluminescence spectra have been revealed. Analysis of the position of these peaks with the Lorentz–Mie theory for light scattering by single dielectric spherical particles confirms that these observed peaks can be regarded as whispering-gallery mode.

We have studied the Raman spectra of a system consisting of a polystyrene latex microsphere coated by CdTe colloidal quantum dots. The cavity-induced enhancement of the Raman scattering allows the observation of Raman spectra from only one CdTe monolayer. Periodic structure with very narrow peaks in the Raman spectra of a single microsphere was detected both in Stokes and anti-Stokes spectral regions, arising from the coupling between the emission from quantum dots and spherical cavity modes.

We report evidence for highly efficient F€ resonance energy transfer between CdTe nanocrystals (donors) and Rhodamine B (acceptors) in mixed solid films. Enhancement of the acceptor photoluminescence intensity and a decrease of the donor decay time are observed in the films containing nanocrystals mixed with Rhodamine B. For a wide range of films with a ratio between the amount of acceptors and the amount of donors of 0.2–5, an efficiency of energy transfer of more than 20% is estimated from time resolved measurements. � 2004 Elsevier B.V. All rights reserved.

The influence of dc electric field is examined on the photoluminescence spectra of various PbI2 nanocrystals in a poly (vinyl alcohol) matrix, prepared by fast and slow cooling of a hot saturated aqueous PbI2 solution. The thin flat PbI2 nanocrystals with a thickness of less than 1 nm exhibit a strong 1D quantum confinement. The application of an electric field of up to 16 kV cm−1 causes a pronounced Stark effect in the differential absorption spectrum and enhancement of excitonic photoluminescence. The last effect results probably from the field-induced detachment of surface-trapped excitons (thermoelectronic ionization or Frenkel effect). While, the larger PbI2 nanocrystals of size 5 nm did not show an appreciable field-induced effect in the photoluminescence spectra. Such different behaviour between large and small nanocrystals demonstrates the dramatic influence of the surface on the excitonic radiative recombination in semiconductor quantum dots.

We report on the efficient photoluminescence up-conversion in colloidally-prepared core-shell CdSe/ZnS quantum dots. We demonstrate that the efficiency of photon energy up-conversion and the magnitude of the spectral shift can be controlled by the thickness of the ZnS shell, the temperature and the excitation intensity. Based on the analysis of the experimental data we propose that intrinsic gap states are involved in the photoluminescence up-conversion as intermediate states rather than nonlinear two-photon absorption or Auger processes.