Red florescent Ag2S-CdS hybrid nanoparticles prepared by a one pot and rapid microwave method

Reviving near infra‐red emission of Ag2S nanoparticles using interfacial defects in the Ag2S@CdS core–shell structure

“…This NIR emission in terms of intensity is comparable with the NIR emission of our recent report on Ag 2 S@ZnS. This finding could be due to the rapid growth of CdS particles and the catalyst role of Ag 2 S in its surface passivation by CdS nucleation . The roughly 50 nm blue shift of both absorption and emission spectra compared with Ag 2 S@ZnS core–shells could be due to the rapid growth of CdS and the smaller size of Ag 2 S cores, as also confirmed by Doh et al .…”

“…The slight blue shift of 10 nm compared with sample B is due to better shell growth and the slight compression of the core structure, which is consistent with the XRD results. Moreover, with increase in irradiation time, the exciton emission peak shrinks to zero and the appearance of red emission indicates growth of the CdS shell . After 12 min of irradiation, two separate peaks were distinguished located at 658 nm and 895 nm.…”

“…ZnS as a shell could passivate the Ag 2 S surface traps and enhance its NIR emission . We also reported, from a different study, that continued microwave irradiation during the preparation of Ag 2 S/CdS hybrid nanoparticles can lead to very strong red emission at room temperature . Thus, the combination of a pulsing method and the growth of CdS with a strong red emission suggested a new pathway for NIR emission of Ag 2 S QDs.…”

“…[16] We also reported, from a different study, that continued microwave irradiation during the preparation of Ag 2 S/CdS hybrid nanoparticles can lead to very strong red emission at room temperature. [17] Thus, the combination of a pulsing method and the Abbreviations used: EDX, energy dispersive X-ray; FWHM, full width half maximum; IDS, interfacial defect states; INSF, Iran National Science Foundation; IR, infra-red; LED, light-emitting diode; NIR, near infra-red; OA, oleic acid; ODE, octadecene; OLA, oleylamine; PL, photoluminescence; QD, quantum dots; SEM, scanning electron microscope; TEM, transmission electron microscope; TGA, thioglycolic acid; XRD, X-ray diffraction. growth of CdS with a strong red emission suggested a new pathway for NIR emission of Ag 2 S QDs.…”

CdSe and CdSe/CdS core–shell QDs: New approach for synthesis, investigating optical properties and application in pollutant degradation

“…Recently, surface modification of the QDs with the other inorganic shells, is an interesting subject of the research, which it can considerably promote the optical properties of QDs. CdSe is an II − VI semiconductor material with excellent physical properties and it is a proper material for the mentioned applications . In most of the previously reported works, CdSe QDs indicates a broad band emission related to the surface defects.…”