Bài viết Khả năng sinh nhiệt của các hạt nano CoxFe3-xO4 trình bày một vài kết quả nghiên cứu cấu trúc, tính chất từ và đốt nóng cảm ứng từ của NPs sắt từ CoxFe3-xO4 (0 ≤ x ≤ 1) được tổng hợp bằng phương pháp thủy nhiệt. | TNU Journal of Science and Technology 227 11 87 - 94 HEATING EFFICIENCY OF CoxFe3-xO4 NANOPARTICLES Le Thi Hong Phong1 2 Pham Hong Nam1 Nguyen Van Dang3 Pham Thanh Phong4 Do Hung Manh1 2 1 Institute of Materials Science VAST 2Graduate University of Science and Technology - VAST 3 TNU - University of Sciences 4Science and Technology Advances Institute Van Lang University ARTICLE INFO ABSTRACT 2 2 Received 01 6 2022 The substitution of Co for Fe ions in CoxFe3-xO4 nanoparticles NPs to change the magnetic anisotropy and coercivity of Fe3O4 NPs is expected to Revised 14 7 2022 increase the heating efficiency SAR of NPs under alternating magnetic Published 14 7 2022 field AMF . However SAR also depends on other parameters such as size shape of NPs as well as frequency and intensity of AMF. This article KEYWORDS presents some results of studying the structure magnetic and heating properties of CoxFe3-xO4 NPs 0 x 1 synthesized by hydrothermal Iron oxide method. The structural and morphological investigations showed that the Cobalt ferrite obtained NPs were single-phase spinel ferrite with mean sizes ranging from 20-50 nm. Magnetic measurements pointed out that saturation magnetization Magnetic nanoparticles MS depended simultaneously on the particle size and Co content. In Superparamagnetism contrast the change of coercive force HC mainly depended on Co content Magnetic inductive heating which gradually increased and reached the highest value at x then decreased as x increased further. Magnetic induction heating results indicated that the presence of Co ions in CoxFe3-xO4 NPs did not lead to an increase of SAR because their coercive force had a higher value than the intensity of AMF. The high SAR value 339 W g of Fe3O4 NPs was due to the simultaneous contribution of relaxation and hysteresis losses and represented their potential application in hyperthermia. KHẢ NĂNG SINH NHIỆT CỦA CÁC HẠT NANO CoxFe3-xO4 Lê Thị Hồng Phong1 2 Phạm Hồng Nam1 Nguyễn Văn Đăng3 Phạm .
