Defect originated photoluminescence tuning of silica nanoparticles prepared by electron beam irradiation and their applications

Size Tuning, Phase Stabilization, and Anticancer Efficacy of Amorphous Selenium Nanoparticles: Effect of Ion-Pair Interaction, −OH Functionalization, and Reuse of RTILs as Host Matrix

“…In this perspective, a methodology of clubbing the radiation-mediated technique with the host matrix of solvents such as room-temperature ionic liquids (RTILs) could be a promising approach. − Electron beam-induced nanomaterial synthesis is a versatile technique with several inherent advantages, such as facileness, nanocharacteristic-maneuvering parameters (such as absorbed dose and dose rate), time efficiency, scale-up potential, and not requiring any external reducing agents. − In the current work, an electron beam was used to generate reducing species, deriving nucleation that eventually leads to the formation of α-Se NPs, while RTILs played multiple roles: as a host matrix, a source of reducing species, and a stabilizer. Nonetheless, apart from the synthesis of α-Se NPs with prolonged stabilization, the main objective of the current work was to investigate the effect of the nature of cation–anion combinations (in RTILs) on the size and phase stability of α-Se NPs.…”

Photoluminescent Silica Nanostructures and Nanohybrids

“…[7] Optical absorption (OA) and photoluminescence (PL) properties of SiO 2 , in mid bandgap energy region, are attributed to intrinsic or extrinsic defects. [8][9][10] Free excitons (FEs), formed by photoexcitation, transfer energy to impurities and structural defects. Intrinsic defect emission is invariably accompanied by nonradiative decay and sometimes, formation of new kinds of defects.…”

“…In spite of being widely studied, the field is rife with anomalies, ambiguities and controversies about the role and chemical nature of point defects associated with different optical bands and their interplay with structural and environmental disorder. [9,[13][14][15][16][17][18][19][20][21] In the present minireview, we shall focus on this aspect of SiO 2 nanoparticles (NPs).…”

“…Amorphous silicon dioxide ( a‐ SiO 2 ) finds extensive application in optical fibers, lenses and optoelectronic devices, by virtue of its wide band gap (E g ∼9 eV), [1–3] optical transparency (visible, UV and vacuum‐UV) [4–6] and low conductivity [7] . Optical absorption (OA) and photoluminescence (PL) properties of SiO 2 , in mid bandgap energy region, are attributed to intrinsic or extrinsic defects [8–10] . Free excitons (FEs), formed by photoexcitation, transfer energy to impurities and structural defects.…”

“…The variety of kinds and environments of defects is manifested in sample‐dependent PL of SiO 2 , which can be observed over the entire range of wavelengths, from IR to UV. In spite of being widely studied, the field is rife with anomalies, ambiguities and controversies about the role and chemical nature of point defects associated with different optical bands and their interplay with structural and environmental disorder [9,13–21] . In the present minireview, we shall focus on this aspect of SiO 2 nanoparticles (NPs).…”