Fig. 1. Flow chart of CoS QDs/PDMS nanocomposite film preparation

Fig. 2. The morphology and component analysis of CoS QDs. (a) TEM image (inset shows the particle size distribution); (b) HR-TEM image; (c) HR-TEM image (inset shows the FFT pattern); (d) AFM image; (e) Height analysis of the particle size at positions 1, 2 and 3 marked in Fig.(d); (f) EDS energy spectrum of CoS QDs

Fig. 3. The component, chemical bond, phase, and vibrational spectrum analysis of CoS QDs. (a) XPS full spectrum; (b) Co 2p XPS spectrum; (c) S 2p XPS spectrum; (d) FTIR spectrum; (e) XRD diffraction pattern; (f) Raman spectrum

Fig. 4. Infrared characterization of CoS QDs and their PDMS nanocomposite films. (a) UV-Vis absorption spectra of CoS QDs solutions (inset: photos of CoS QDs solutions under natural and UV light); (b) UV-Vis absorption spectra of CoS QDs films; (c) UV-Vis absorption spectra of CoS QDs of PDMS and CoS QDs/PDMS nanocomposite films; (d) PL spectra of CoS QDs solution; (e) PL spectra of normalized CoS QDs; (f) PL spectra of NIR CoS QDs; (g) PLE spectra of CoS QDs; (h) PLE spectra of CoS QDs; (i) PLE spectra of NIR CoS QDs; (j) PL spectra of PDMS plots; (k) PL spectra of CoS QDs/PDMS nanocomposite films; (l) PL spectra of near-infrared CoS QDs/PDMS nanocomposite films