Waste-driven single crystalline sulphur-doped GQDs are synthesized via a green hydrothermal route with the highest quantum yield and excellent biocompatibility for bioimaging.

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Self-organized pattern evolution on SiO surface under low energy Ar-ion irradiation has been investigated extensively at varied ion energies, angles of ion incidence, and ion flux. Our investigations reveal an instability on SiO surface in an angular window of 40° ̶ 70° and for a comprehensive range of Ar-ion energies (200-1000 eV). Different topographical features, viz. ripples, mounds, and elongated nanostructures evolve on the surface, depending upon the angle of incidence and ion fluence. The results are compiled in the form of a parametric phase diagram (ion energy versus angle of incidence) which summarizes the pattern formation on SiO surface. To understand the evolution of observed patterns, we have carried out theoretical estimation, taking into account the synergetic roles of ion induced curvature-dependent sputter erosion and prompt atomic redistribution. It is shown that irradiation-induced mass redistribution of target atoms plays a crucial role in determining the critical angle of ion incidence for pattern formation on SiO under the present experimental conditions, whereas the contribution of curvature-dependent sputtering needs to be considered to understand the existence of the angular window of pattern formation. In addition, ion-beam shadowing by surface features are shown to play a dominant role in the formation of mounds and elongated structures at higher ion fluences.

Non-covalently functionalized PFNGS, exhibiting exceptional biocompatibility, were employed for sensing nitric oxide with high temporal resolution.

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Since precise control of nanoscale features is in high demand, it is being exploited to develop and improve OSL dosimetric materials, where striking improvement might also be expected in lanthanide-doped metal halides. The major challenge in the development of a nanophosphor lies in avoiding the aggregation of a dopant element in host materials, which has long prevented an in-depth exploration for the same purpose. This study focuses on the synthesis and characterization of Sm-doped KCl nanophosphors to develop a novel accession to investigate the highly sensitive trivalent Sm-doped KCl phosphor. Herein, we were able to overcome the aggregation phenomena and we showed that Sm-doped KCl with 0.45 mol% of Sm, which is the optimised dopant concentration, exhibits the high-intensity luminescence performance under blue light stimulation for the gamma doses in the range from 100 mGy to 1000 Gy.This sensitivity is attributed to the uniform nanospheres encapsulated in KCl along with the predominant existence of a trivalent (Sm 3+ ) state, where these conditions can introduce additional defects centres.The presence of these additional defect centres was confirmed by photoluminescence studies, plausibly supporting the charge transfer due to the optical energy between these states, leading to high sensitivity.To establish KCl:Sm as a good OSL dosimetric materials (DM), we investigated fading, reusability, and reproducibility and compared these with those of commercial DM compounds such as Al 2 O 3 :C and BeO. Overall, Sm-doped KCl is non-toxic, cost-effective, robust, and a promising candidate for reusable dosimetry.

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