Efficient near-infrared emission from neodymium by broadband sensitization of bismuth in zeolites.

Nd-Bi codoped zeolites were prepared by an ion-exchange process, and the optical properties were investigated by photoluminescence (PL) and PL excitation spectra, and decay time measurements. The results show that the NIR emission of Nd3+ ions is significantly enhanced by the introduction of bismuth in codoped samples, and the lifetime reaches 246 μs. It is also observed that NIR-active Bi acts as a sensitizer of Nd3+ ions. The energy transfer efficiency is also estimated. The peculiar optical properties make Nd-Bi codoped zeolites promising for potential application in biological probes.