Optical properties and thermal sensitivity of AgInS2 and AgInS2/ZnS quantum dots embedded in barium sulphate and calcium carbonate matrices

Quantum dots of AgInS2 and AgInS2 doped with ZnS were embedded in microscale spherical BaSO4 and CaCO3 matrices by co-precipitation approach. Energy dispersive X-ray analysis (EDX) confirmed the homogeneous distribution of quantum dots within the matrices. The effect of encapsulation on the optical properties of quantum dots (QDs) and the dependence of photoluminescence (PL) spectra on temperature were investigated. The similar appearance of the spectra and the same position of the emission maximum for the composites with BaSO4 and CaCO3 indicate that the nature of the matrix does not significantly affect the spectral characteristics of quantum dots. While the application of composites based on CaCO3 at high temperatures is limited due to the degradation, composites with BaSO4 demonstrate high stability and thermal sensitivity (1.89 +/- 0.0012 %/K). Therefore, the composites we studied are well-suited for light conversion and optical temperature sensing applications.