Preparation and Properties of Carbon Dot-Grafted CaAl12O19: Mn4+ Color-Tunable Hybrid Phosphor

Abstract

A series of carbon dots (CDs) grafted CaAl12O19:Mn4+ (CAO) color-tunable hybrid phosphors have been synthesized via a facile sol-gel method. Through the hydrolysis and condensation reactions of the silica precursor, CDs can be incorporated into highly flexible hybrid materials through combining with a CaAl12O19:Mn4+ phosphor within silica gel networks for the fabrication of flexible displays and multicolor luminescent materials. By tuning the mass ratio of CDs/CAO and by adjusting the excitation wavelength, the color of the luminescence can be systematically tailored from purplish-red (0.504, 0.250) to greenish-blue (0.238, 0.192). Furthermore, the temperature-dependent luminescent properties of the CDs/CAO phosphors makes them suitable as thermometers with a wide linear temperature sensing range from 80 to 300 K. Easily tunable color displays are obtained by incorporating carbon dots (CDs) into highly flexible hybrid materials. By carefully controlling the concentration of CDs in relation to that of the used CaAl12O19:Mn4+ phosphor (CAO) and by changing the excitation wavelength, the obtained hybrid phosphors exhibit tunable colorful luminescence. The CD/CAO phosphors show great potential in multicolor displays and luminescent thermometers with a sensing temperature range from 80 to 300 K. Copyright