Luminescent properties and energy transfer of luminescent carbon dots assembled mesoporous Al2O3: Eu3+ co-doped materials for temperature sensing

Abstract

Owning to the hydrogen-band interactions, blue-light-emitting luminescent carbon dots (CDs) synthesized by one-pot hydrothermal treatment were successfully assembled into Eu3+ doped mesoporous aluminas (MAs). Interesting, dual-emissive CDs/MAs co-doped materials with higher quantum yield (QY), long-term stability, mesoporous structure, high thermal stability, and large surface areas were obtained. Furthermore, the obtained CDs/MAs co-doped materials possessed tunable color, and excellent temperature sensitivity due to the existing of energy transfer between CDs and Eu3+ ion. The energy transfer efficiency (η) and energy transfer probability (P) for CDs/Eu3+ co-doped materials possessed a monotonous tendency with the change of Eu3+ content. More importantly, the dual-emissive colors can be regularly adjusted through regulating their excitation wavelength or relative mass ratio. In addition, the emission intensity of the CDs/MAs co-doped materials gradually decreased with increasing temperature showing the clear temperature dependence, this dual-emissive thermometer was with high sensitivity, owning a great fitted curve in the range from 100 to 360K under a single wavelength excitation.