Synthesis and Room Temperature d~o Ferromagnetic Properties of α-MoO3 Nanofibers

Herein,we report the magnetic properties of α-MoOnanofibers synthesized via a hydrothermal method.X-ray photoelectron and Raman spectroscopic studies have been employed to evidence the presence of oxygen vacancy defects in the α-MoOnanofibers.To elucidate the oxygen vacancy related ferromagnetism,post-thermal annealing in oxygen and vacuum was performed.The UV emission band of α-MoOnanofibers reveals a red shift from oxygen annealed to vacuum annealed,indicating a bandedge reduction.The saturation magnetization of oxygen annealed nanofibers decreases while that of vacuum annealed nanofibers increases.These results strongly confirm that the oxygen vacancies play a significant role in inducing ferromagnetism.The origin of ferromagnetism may be due to the exchange interactions among localized electron spin moments resulting from oxygen vacancies of α-MoOnanofibers.The presence of such defects was further supported by the photoluminescence measurements.