Surface enhanced strong visible photoluminescence from one-dimensional multiferroic BiFeO3 nanostructures

The surface defect dominated visible emission from one-dimensional multiferroic BiFeO₃ (BFO) nanowires (NWs) is characterized by photoluminescence (PL) spectroscopy. The PL spectra of BFO NWs exhibit a weak near band emission (NBE) along with a strong defect-level emission (DLE). It is suggested that excess surface defects exist in BFO NWs which are responsible for strong visible green emission. Passivation of BFO NW surface with H₂ significantly improves the NBE emission while suppressing surface recombination. Such a surface enhanced emission promises many potential applications of BFO NWs not only in photonic devices such as LEDs but also in fluorescence-based chemical sensing.