부산대학교 도서관

Single-phase La-substituted bismuth ferrite (Bi $_{\boldsymbol {1-x}}$ La $_{\boldsymbol {x}}$ FeO $_{\mathbf {3}}$ ) nanoparticles have been synthesized by thermal decomposition of a glyoxylate precursor. The crystal structure transition of BiFeO $_{\mathbf {3}}$ from the rhombohedral (R3c) to the cubic $\boldsymbol {Pm}\bar {\mathbf {3}}\boldsymbol {m}$ structure by La addition was confirmed by X-ray diffraction and infrared spectrometry methods. Furthermore, the Bi $_{\boldsymbol {1-x}}$ La $_{\boldsymbol {x}}$ FeO $_{\mathbf {3}}$ nanoparticles showed a weak ferrimagnetism behaviour, while the magnetization increased from 0.18 to 0.48 emu g $^{\mathbf {-1}}$ with La substitution. The Bi $_{\boldsymbol {1-x}}$ La $_{\boldsymbol {x}}$ FeO $_{\mathbf {3}}$ nanoparticles exhibited strong absorption in the visible region with the optical band gap calculated from Tauc's plot in the range of 2.19-2.15 eV. Furthermore, the effects of La substitution on the photodegradation of the methylene blue (MB) under visible light were also studied. The photodegradation of MB dye was enhanced from 64 to $\sim $ 99% with increasing La substitution from $\boldsymbol {x =}$ 0 to 0.1 and then decreased to 8% for $\boldsymbol {x =}$ 0.15. [ABSTRACT FROM AUTHOR]