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Borosilicate glass system (SiO 2 :B 2 O 3 :Na 2 O:ZnO) with the addition of 3 wt% CdS was prepared by conventional melt quench technique. Amorphous nature of glass sample was confirmed from XRD measurement. CdS QDs were grown in the glass matrix using an optimized heat treatment schedule in between glass transition (T g) and crystallization (T c) temperature. The phases of CdS QDs were noted by XRD and confirmed by HRTEM. Optical absorption study was carried out to measure the energy band gap and it is found that the energy band gap decreases with an increase in the size of QDs. Size determination was done by optical absorption spectra and match with HRTEM results. This change in the size of QDs was confirmed by PL spectra. The optimized glass sample was used for the degradation of methyl orange (MO) dye. Unlabelled Image • Borosilicate glass system doped with CdS semiconductor was prepared by conventional melt quench technique. • Growth of CdS QDs was controlled by optimized heat treatment schedule and confirmed by various characterization techniques. • The size of CdS QDs increases and energy band gap decreases with increasing annealing time. • Optical properties were tuned by controlling size of CdS QDs. • CdS QDs embedded in glasses shows MO dye degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Glass system containing Ag-TiO 2 QDs was prepared by the melt quench technique. • Due to addition of Ag in TiO 2 , the band gap tunes in visible light region. • Glasses containing Ag-TiO 2 QDs has been effectively utilized for dyes degradation. • The hydro-photo stability improved due to the incorporation in the glass matrix. Borosilicate glasses with Ag-TiO 2 were successfully prepared by the melt quench technique. Ag-TiO 2 quantum dots (QDs) were grown by heat-treatment (HT) schedule and confirmed by XRD study. The size of the glass powder was determined by SEM and found to be 1.757 µm which was confirmed FESEM cluster formation. FTIR spectra examined the structural changes that occurred in glasses on heat-treatment. The size determination of QDs was done by HRTEM and found to be 6.45 nm. The shift in band edge towards a longer wavelength and increase in absorption intensity of plasmonic peak with an increase in heat-treatment time entails the increase in size of QDs with heat-treatment and a decrease in the band gap. Incorporation of Ag-TiO 2 QDs in the inert glass matrix exhibits a superior photocatalyst for indigo carmine (IC) and eosin Y (EY) dyes degradation and good stability with near initial capacity under irradiation of visible light. [ABSTRACT FROM AUTHOR]

In this paper, sodium borosilicate glass SiO 2 -B 2 O 3 -Na 2 O-ZnO with 2 wt% CdS and 1 wt% TiO 2 were prepared by the melt quench technique. For the growth of QDs, single-step heat treatment was given using glass transition (T g) and glass crystallization (T c) temperature. Hexagonal and anatase phase of grown CdS and TiO 2 QDs were confirmed by XRD pattern. The size of powders was observed by SEM and cluster formation of CdS/TiO 2 QDs was studied by FESEM. EDS pattern confirms the elemental composition which was used during synthesis. The structural changes due to heat treatment were explored by FTIR study. The growth of QDs and size determination was done by HRTEM. An increase in the size of QDs with annealing time was confirmed by optical absorption and emission spectra. Photocatalytic activity of Cd3:3 h (5.33 μm) and Cd3:5 h (3 μm) is investigated by degrading indigo carmine (IC) dye and degradation efficiency was found to be 85.30% and 91.64% respectively for 5 h. Unlabelled Image • CdS/TiO 2 QDs were grown in glasses by single step heat treatment. • CdS improves the absorbing capability of TiO 2 QDs in visible light. • Effect of CdS/TiO 2 QDs doped glass powder size on IC dye degradation is tested. • Synthesized CdS/TiO 2 QDs doped glasses showed better efficiency for the IC dye degradation. [ABSTRACT FROM AUTHOR]

An inhibition of pathogenic bacteria using light source is an attractive phenomenon. The present study is based on the application of CdS quantum dots (QDs) grown in the glass matrix for growth inhibition of bacteria. Glass system 36SiO 2 –15B 2 O 3 –15Na 2 O–9K 2 O–25ZnO with 3 wt % CdS was prepared by the melt-quench technique. CdS QDs were grown in glass matrix with single-step heat treatment and characterized by XRD, HRTEM, XPS, and micro-Raman for phase identification. Their size related to quantum confinement properties were studied with optical absorption (UV–Vis), photoluminescence (PL) spectroscopy. The structural and optical studies confirm the growth of CdS QDs in a glass matrix which was then utilized for antimicrobial activity. The generation and recombination of electron-hole pairs by CdS QDs due to absorption of light were responsible for the formation of reactive oxygen species (ROS). The use of these ROS in bacterial colonies inhibition has been discussed. Image 1 • Glasses were prepared by conventional melt quench technique. • Glasses were heat treated by optimized single stage heat treatment schedule. • Growth of CdS QDs was confirmed by XRD, RAMAN, HRTEM, and XPS. • Optical properties were studied by UV–Vis and Photoluminescence. • Antimicrobial activity of CdS QDs on S. aureus and E. coli bacteria is discussed. [ABSTRACT FROM AUTHOR]