Figure 1.

Fabrication and characterization of CsPbBr₃ quantum dots (QDs) inside transparent amorphous matrix. a) XRD patterns of precursor glass (PG), CsPbBr₃ QDs with and without Eu dopant in GC. b) TEM image of CsPbBr₃ QDs without Eu dopant in glass (quantum dot size distribution shown in inset). c) HRTEM image of CsPbBr₃ GC. d) TEM image of CsPbBr₃:Eu GC (quantum dot size distribution shown in inset). e) Transmittance spectra of CsPbBr₃:xEu QDs in glass as a function of Eu concentration (transmittance spectrum of PG measured as a reference). f) Photographs of CsPbBr₃ GC, CsPbBr₃:1.5%Eu GC (optimal concentration of Eu dopant) and conventional CsPbBr₃ nanocrystal film with thickness of about 100 µm (CsPbBr₃ nanocrystals and polystyrene are uniformly mixed with the ratio of 1:5). g) Pb 4f XPS spectra of CsPbBr₃ GC with and without Eu dopant. h) Eu 3d_5/2 XPS spectrum of CsPbBr₃:1.5%Eu GC. i) Photoluminescence (PL) spectra of CsPbBr₃:xEu GC as a function of Eu concentration under 365 nm UV excitation (photograph of CsPbBr₃:1.5%Eu GC emission and enlargement of Eu³⁺ emission shown in the inset). PL spectra is measured with integrating sphere to ensure fair comparison