Effect of crystal structures on energy transfer behavior from Bi3+ to Eu3+ in alkaline earth metalstannates

A single phased color-tunable phosphor via energy transfer has drawn much attention, whereas it is still a question that how to choose a suitable host to realize an efficient energy transfer. In this work, novel single Bi3+ or Eu3+ doped and Bi3+, Eu3+ co-activated Ca2SnO4 (CSO) and Sr2SnO4 (SSO) phosphors have been prepared through a high temperature solid state reaction. The energy transfer happening from hosts to Eu3+ has been confirmed. By co-doping of Bi3+, a brighter red light is realized which is attributed to the much more efficient energy transfer from Bi3+ to Eu3+. After comparison, the energy transfer efficiency from Bi3+ to Eu3+ is much higher in CSO:Bi3+, Eu3+ than that in SSO:Bi3+, Eu3+. Furthermore, the experiment reveals that the single-phased color-tunable phosphors exhibit excellent resistance against thermal quenching, suggesting that they can be potential candidates in UV-pumped white light emitting diodes (LEDs).