Achieving power-dependent fluorescence intensity ratio via enhanced photothermal effect in rare-earth and CaCu3TiO12 co-doped alkali niobate ceramics

Abstract

Controlling the laser power density is one of the major means to bring photothermal conversion phenomenon. However, only a slight temperature enhancement was achieved by exposure to the laser. How to enhance photothermal conversion to develop power-sensitive fluorescence intensity ratio technology becomes a problem. Here, we report an eco-friendly niobate-based ceramic (K 0.25 Na 0.25 NbO 3 ) doped with rare earth ions (Er 3+ , Yb 3+ ) and simultaneously modified with CaCu 3 TiO 4 , exhibiting superior photothermal effect (PTE) and fluorescence intensity ratio (FIR). Thereinto, PTE originating from the up-conversion luminescence of Er 3+ greatly elevates due to the Cu 2+ quenching and Yb 3+ sensitization. Meanwhile, the defects formed by the volatilization of potassium and sodium at high temperature can enhance PTE (70 °C, 0.4 W) and power sensitivity ( S p = 0.61 W -1 ). Under multiple power cycles, stable FIR of the ceramic shows outstanding resistance to temperature in long-term power-dependent tests. Furthermore, this strategy can open opportunities for preparing efficient photothermal conversion ceramics and exploiting PTE for vision-to-tactile sensory conversion.