[en] Low cost and easy biodegradability makes the deep eutectic solvents (DESs) viable alternative to expensive ionic liquids (ILs).Thus, DESs promise wide ranging applications including nanomaterial synthesis, dearomatization of gasoline and CO₂ sequestration. DESs have been marked as electrolyte for dye-sensitized solar cell, and in redox flow battery as catholyte or anolyte. In all these advanced energy related applications electron transport and transfer events are integrally involved. The C₃₇ value, a measure of the efficiency of scavenging pre-solvated electrons is the highest in ethaline in case of nitrate ions, which indicates the slowest solvation process in this DES. The pre-solvated electron capture by a DNA base, an aspect considered to be important in cancer radiotherapy, could be monitored conveniently in these liquids at much longer time scale, compared to those reported in aqueous solutions. Bimolecular rate constants for the reaction of solvated electrons with nitrate and the DNA base have been calculated, and compared in the three DESs. These experimentally obtained values are comparable to the diffusion controlled rate constants in DESs. (author)

[en] Bilirubin (BR) plays two extreme roles in physiology, one hand it is a toxic metabolite while at micromolar concentration it acts as antioxidant. It has been observed that hydroxyl, glutathiyl and Linoleic peroxyl radicals abstract hydrogen atom from bilirubin, whereas N₃, Br₂, CCl₃OO, NO₂ radicals react via single electron transfer action. Our study demonstrates that oxidation of bilirubin occurs via both hydrogen atom transfer and single electron transfer depending on the nature of the radical. (author)

[en] Existence, yield, and properties of solvated electrons in three deep eutectic solvents, reline, ethaline, and glyceline composed of choline chloride as hydrogen bond acceptor and urea, ethylene glycol (EG) and glycerol (Gly) as hydrogen bond donors, respectively at a molar ratio of 1:2 have been compared. The varied transient absorption spectra of solvated electrons in these DESs have been explained on the basis of polarity, hydrogen bonding effect and the moieties responsible for creating the environment for solvation. The yield and average life time follow the trends in viscosity as well as the reactivity of electrons with the components. The C₃₇ value, a measure of the efficiency of scavenging pre-solvated electrons is the highest in ethaline in case of nitrate ions, which indicates the slowest solvation process in this DES. (author)

[en] Owing to the wide-ranging applications, Selenium (Se), especially in its amorphous form (a-Se) has gained a lot of attention in the arena of nanoscience in recent times. However, applications of ‘a-Se’ NPs are limited due to their meticulous synthetic procedures and rapid phase transformation leading to low stability. In this perspective, a facile approach targeted towards the synthesis of primarily a-Se NPs (with long term phase stability) has been formulated by integrating the radiolytic technique with the host matrix of solvents such as room temperature ionic liquids (RTILs). Besides, the effect of the nature of ionic combinations (in RTILs) on their size and the phase stability was also investigated. For the said purpose, three RTILs were used as follows: 1-ethyl-3-methyl imidazolium boron tetrafluoride ((EMIM)(BF₄)), 1-(2-hydroxyethyl)-3-methylimidazolium boron tetrafluoride ((EOHMIM)(BF₄)) and 1-ethyl-3-methylimidazolium methane sulfonate ((EMIM)(MS)). The synthesis of a-Se NPs has been briefly discussed as follows. An optimized amount of SeO₂ was dissolved in aforementioned RTILs followed by e-beam irradiation (optimized absorbed dose ~80 kGy). Post-irradiation, the solution colour changed to brick-red, which indicated the formation of NPs. The precipitates were obtained by centrifugation and characterized. The results of the study have been discussed in this article

[en] Radiation chemistry can be used to study reactions of free radicals not only in homogeneous medium but also in micro-heterogeneous medium, microemulsion being typical example of this type of medium. This article intends to summarize some radiation chemical studies in microemulsion using pulse radiolysis as a tool. Attempt has been made to show that the reaction and self-decay of hydrated electron can lead to achieve useful results relating to the physical properties of micro-droplets. Moreover, free radical reactions with biomolecules in these media can sometime be extrapolated to living systems. (author)

[en] Futuristic applications of nanomaterials are imminent, therefore to meet their growing demands, the development of time-efficient, facile, eco-friendly and sustainable synthetic protocols is very much desirable. In this pretext, radiation-assisted approach can play an important role in addressing some of the aforementioned vital issues being faced by other conventional methodologies. (author)

[en] Impending applications of room temperature ionic liquids (RTILs) in the areas involving high radiation fields (nuclear fuel cycle and space) requires microscopic understanding of the radiation induced perturbations in their molecular structure. Here in, the photophysical properties of the post-irradiated imidazolium ILs revealed significant changes in their molecular structure and bonding interactions, however their physicochemical properties do not change significantly, even at high absorbed doses. (author)

[en] CdSe quantum dots (QDs) were synthesized by a rapid and one step templated approach inside the water pool of AOT (sodium bis(2-ethylhexyl) sulfosuccinate) based water-in-oil microemulsions (MEs) via electron beam (EB) irradiation technique with high dose rate, which favours high nucleation rate. The interplay of different experimental parameters such as precursor concentration, absorbed dose and ${\mathcal{W}}_0$ values (aqueous phase to surfactant molar ratio) of MEs were found to have interesting consequences on the morphology, photoluminescence (PL), surface composition and carrier recombination dynamics of as-grown QDs. For instance, highly stable ultrasmall (∼1.7 nm) bluish-white light emitting QDs were obtained with quantum efficiency (η) of ∼9%. Furthermore, QDs were found to exhibit tunable broadband light emission extending from 450 to 750 nm (maximum FWHM ∼180 nm). This could be realized from the CIE (Commission Internationale d’Eclairage) chromaticity co-ordinates, which varied across the blue region to the orange region thereby, conferring their potential application in white light emitting diodes. Additionally, the average PL lifetime $(⟨\mathrm{\tau <!--\; ??\; -->}⟩)$ values could be varied from 18 ns to as high as 74 ns, which reflect the role of surface states in terms of their density and distribution. Another interesting revelation was the self-assembling of the initially formed QDs into nanorods with high aspect ratios ranging from 7 to 20, in correspondence with the ${\mathcal{W}}_0$ values. Besides, the fundamental roles of the chemical nature of water pool and the interfacial fluidity of AOT MEs in influencing the photophysical properties of QDs were investigated by carrying out a similar study in CTAB (cetyltrimethylammonium bromide; cationic surfactant) based MEs. Surprisingly, very profound and contrasting results were observed wherein $⟨\mathrm{\tau <!--\; ??\; -->}⟩$ and η of the QDs in case of CTAB MEs were found to be at least three times lower as compared to that in AOT MEs. (paper)

[en] In the present study photoluminescent tin di-oxide nanoparticles have been successfully synthesized in the deep eutectic solvent reline as the host matrix via electron beam irradiation. Reline acts as the stabilizing medium as well as the in situ source of radicals which carry out the synthesis. The effect of dose on the bang gap of the nanomaterial has been studied. The synthesized nanoparticles have been characterized using XRD, XPS, SAED and TEM. (author)

[en] Silicon (Si) has received a great deal of attention in the field of nanoscience and nanotechnology over the past three decades due to its excellent biocompatibility, natural abundance and cost-effectiveness. Considering the imminent importance of Si nanomaterials (NMs) in various areas, a highly rapid, eco-friendly, and one-pot scalable approach based on radiation-induced technique is being reported for their preparation. In order to tune the photoluminescence (PL) properties, different metal ions were doped into SiONCs. For instance, on doping with Mn²⁺ ions, the PL of SiONCs exhibited tunability from blue to green region. This is an indication of the tetrahedrally coordinated Mn²⁺ ions in the matrix of SiONCs. In addition to this, lanthanides such as Eu³⁺ and Tb³⁺ were doped into SiONCs, which resulted in significant changes in their PL properties. The as obtained doped SiONCs were explored for the sensing of toxic metal ions. Detailed analysis and the possible sensing mechanism will be discussed