Upconversion luminescence modification induced near infrared luminescence enhancement of Bi2Ti2O7:Yb3+, Er3+ inverse opals

To date, there are comprehensive researches on rare-earth doped photonic band gap (PBG) materials. The PBG materials can effectively modify the up-conversion luminescence (UCL) of rare earth ions. However, few people pay attention to the influence of modification of the UCL of rare earth ions on their near infrared (NIR) luminescence. In this article, the Bi2Ti2O7: Yb3+, Er3+ inverse opal PBG materials were prepared, and the influence of modification of the UCL of Er3+ on their NIR luminescence was investigated systematically by changing the PBG position. The green and red UCL were suppressed when the PBG was overlapped the UCL of Er3+. The UCL modification induced NIR luminescence enhancement was observed in the Bi2Ti2O7: Yb3+, Er3+ inverse opal, which was attributed to the energy redistribution caused by the PBG effect. The suppression of UCL results in that the electrons located at the UCL levels relax to the NIR luminescence level of I-4(13/2), causing the NIR luminescence enhancement. Our research can provide a promising method for the enhancement of the NIR luminescence.