Home
Giới thiệu
Tài khoản
Đăng nhập
Quên mật khẩu
Đổi mật khẩu
Đăng ký tạo tài khoản
Liệt kê
Công trình khoa học
Bài báo trong nước
Bài báo quốc tế
Sách và giáo trình
Thống kê
Công trình khoa học
Bài báo khoa học
Sách và giáo trình
Giáo sư
Phó giáo sư
Tiến sĩ
Thạc sĩ
Lĩnh vực nghiên cứu
Tìm kiếm
Cá nhân
Nội dung
Góp ý
Hiệu chỉnh lý lịch
Thông tin chung
English
Đề tài NC khoa học
Bài báo, báo cáo khoa học
Hướng dẫn Sau đại học
Sách và giáo trình
Các học phần và môn giảng dạy
Giải thưởng khoa học, Phát minh, sáng chế
Khen thưởng
Thông tin khác
Tài liệu tham khảo
Hiệu chỉnh
Số người truy cập: 107,320,872
Detailed microwave loss mechanisms for nanocomposites of La-doped BaFe12O19 and polyaniline
Tác giả hoặc Nhóm tác giả:
P.T. Tho, N. Tran , N.Q. Tuan, T.A. Ho , C.T.A. Xuan , H.N. Toan, B.W. Lee
Nơi đăng:
Ceramics International (J);
S
ố:
49 (14);
Từ->đến trang
: 23669-23679;
Năm:
2023
Lĩnh vực:
Khoa học;
Loại:
Bài báo khoa học;
Thể loại:
Quốc tế
TÓM TẮT
To mitigate the undesirable effects of electromagnetic pollution on the precise instrument, biological health, and human life, high-efficiency microwave-absorbing materials (MAMs) have been pursued by the scientific community. MAMs also have important potential for information security, 5G, energy harvesting, reduced radar cross-section, and military stealth technology. In this work, magnetic/dielectric composites of La-doped BaFe12O19 (La-BaM) and polyaniline (PANI) were developed to be MAMs. Composites with no and 30% of La concentration (named M0-C and M3-C, respectively) showed poor microwave absorption performance with reflection loss (RL) values of about −20 dB, meaning 99% of the incident microwave was absorbed. The effective absorption bandwidths (EABs) were narrow, with values of 0.70 and 1.55 GHz, respectively. In contrast, the microwave absorption performance of composites with 10% and 50% of La concentration (named M1-C and M5-C, respectively), reached excellent values in both RL and EAB of −47.83 and −43.53 dB and 3.98 and 3.43 GHz, respectively. These RL values implied that 99.99% of the incident microwave could be absorbed. The superior microwave absorption properties of M1-C and M5-C composites could be attributed to their excellent impedance matching, better natural ferromagnetic resonance, exchange resonance, and better attenuation constant. The loss mechanism of microwave energy in La-BaM/PANI composites could be attributed to interfacial polarization at the interfaces of two phases, dipole polarization and micro-current and conductive loss (from PANI), eddy current (from La-BaM), multiple reflection and scattering (from the dispersion of PANI into La-BaM), as well as thermal energy dissipation (from embedding La-BaM/PANI into the epoxy matrix).
ABSTRACT
To mitigate the undesirable effects of electromagnetic pollution on the precise instrument, biological health, and human life, high-efficiency microwave-absorbing materials (MAMs) have been pursued by the scientific community. MAMs also have important potential for information security, 5G, energy harvesting, reduced radar cross-section, and military stealth technology. In this work, magnetic/dielectric composites of La-doped BaFe12O19 (La-BaM) and polyaniline (PANI) were developed to be MAMs. Composites with no and 30% of La concentration (named M0-C and M3-C, respectively) showed poor microwave absorption performance with reflection loss (RL) values of about −20 dB, meaning 99% of the incident microwave was absorbed. The effective absorption bandwidths (EABs) were narrow, with values of 0.70 and 1.55 GHz, respectively. In contrast, the microwave absorption performance of composites with 10% and 50% of La concentration (named M1-C and M5-C, respectively), reached excellent values in both RL and EAB of −47.83 and −43.53 dB and 3.98 and 3.43 GHz, respectively. These RL values implied that 99.99% of the incident microwave could be absorbed. The superior microwave absorption properties of M1-C and M5-C composites could be attributed to their excellent impedance matching, better natural ferromagnetic resonance, exchange resonance, and better attenuation constant. The loss mechanism of microwave energy in La-BaM/PANI composites could be attributed to interfacial polarization at the interfaces of two phases, dipole polarization and micro-current and conductive loss (from PANI), eddy current (from La-BaM), multiple reflection and scattering (from the dispersion of PANI into La-BaM), as well as thermal energy dissipation (from embedding La-BaM/PANI into the epoxy matrix).
[
la-bam-300a_ceri_36480.pdf
]
© Đại học Đà Nẵng
Địa chỉ: 41 Lê Duẩn Thành phố Đà Nẵng
Điện thoại: (84) 0236 3822 041 ; Email: dhdn@ac.udn.vn