Bi_(5)FeTi_(2.5)Co_(0.5)O_(15)(BFTC)ceramics was successfully synthesized using the sol-gel method.It exhibits simultaneously visible-light response,ferroelectric and weak ferromagnetic orders at room temperature.The ...Bi_(5)FeTi_(2.5)Co_(0.5)O_(15)(BFTC)ceramics was successfully synthesized using the sol-gel method.It exhibits simultaneously visible-light response,ferroelectric and weak ferromagnetic orders at room temperature.The narrow band gap of 2.06 eV was determined via the UVevis diffuse absorption spectrum.The x-ray photoelectron spectroscopy results show that the Fe ions in the samples is 3 t and 2 t valence states while the doped Co ions is 2 t valence state.The BFTC sample undergoes a ferromagnetic-like transition at~552 K.Weak ferromagnetism is mainly due to spin-canting of Fe-based and Co-based sublattices via Dzyaloshinskii-Moriya(DM)interaction.Dielectric loss and dielectric modulus exhibit the characteristics of dielectric relaxation,which can be ascribed to oxygen/vacancy hopping.These results reveal many potentially useful physical phenomena and open a new avenue to design of novel solar-energy conversion devices and multiferroic applications.展开更多
基金the National Science Foundation of China(Grant No.51402256 and Grant No.11374227)Natural Science Foundation of Jiangsu Province,China(No.BK 20161409)the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province,China(Grant No.12KJB140013).
文摘Bi_(5)FeTi_(2.5)Co_(0.5)O_(15)(BFTC)ceramics was successfully synthesized using the sol-gel method.It exhibits simultaneously visible-light response,ferroelectric and weak ferromagnetic orders at room temperature.The narrow band gap of 2.06 eV was determined via the UVevis diffuse absorption spectrum.The x-ray photoelectron spectroscopy results show that the Fe ions in the samples is 3 t and 2 t valence states while the doped Co ions is 2 t valence state.The BFTC sample undergoes a ferromagnetic-like transition at~552 K.Weak ferromagnetism is mainly due to spin-canting of Fe-based and Co-based sublattices via Dzyaloshinskii-Moriya(DM)interaction.Dielectric loss and dielectric modulus exhibit the characteristics of dielectric relaxation,which can be ascribed to oxygen/vacancy hopping.These results reveal many potentially useful physical phenomena and open a new avenue to design of novel solar-energy conversion devices and multiferroic applications.