In modern detection technology, the integration of lidar and microwave radar significantly increases the risk of exposure for high-value military equipment. Developing materials with multi-band stealth compatibility is a critical countermeasure to mitigate detection risks. In this study, a brownish-yellow samarium iron oxide material compatible with both 1.06 μm laser stealth and radar stealth was synthesized using the co-precipitation method, whose properties can be tuned by varying the raw material ratios. When the samarium-to-iron (Sm:Fe) ratio was 3:7, the primary crystalline phase was Sm 3 Fe 5 O 12 . Conversely, at Sm:Fe ratios of 1:1, the primary crystalline phase shifted to perovskite-type SmFeO 3 . Notably, Sm 3 Fe 5 O 12 material, prepared with a samarium-to-iron molar ratio of 3:7 and sintered at 800°C, demonstrated a reflectivity of 29.6 % at 1064 nm and excellent microwave absorption performance at 14.64 GHz, achieving a minimum reflection loss (RL min ) of −24.56 dB at a thickness of 4 mm and the effective absorption bandwidth of 1.36 GHz (13.76–15.12 GHz). This study provides a simple method for synthesizing brownish – yellow magnetic samarium iron oxide, which shows wide application in laser stealth, radar stealth and visual camouflage in plateau desert environments.
Muhammad Yousaf,Majid Niaz Akhtar,M.A.K. Yousaf Shah,Sajid Rauf,Naveed Mushtaq,Asma Noor,Muhammad Akbar,Muhammad Afzal,Baoyuan Wang
Rare earth element doping is a popular methodology for improving the electrical and electrochemical properties of materials. Inspired by this ideology, garnet ferrite material Sm 3 Fe 5 O 12 (SFO) doped by rare earth (Yb, La) metal ions to form Sm 3-0.5 Yb 0.5 Fe 5 O 12 (SYFO) and Sm 3-0.5 La 0·5 Fe 5 O 12 (SLFO). The samples are synthesized by sol gel auto combustion and have been applied as electrolyte membrane for the first time in low temperature solid oxide fuel cell (LT-SOFC). The results indicate that the as-prepared materials have triple charge transport (H + /O −2 /e − ) carrier which promotes the hydrogen oxidation reaction (HOR) and oxygen reduction reactions (ORR) in SOFC at triple phase boundary region (TPB). Electrochemical impedance spectroscopy (EIS) reveals that the polarization resistance of SLFO membrane significantly reduces from 0.92 Ω-cm 2 to 0.45 Ω-cm 2 and the power output improve from 310 mW/cm 2 to 650 mW/cm 2 at 550 °C temperature in comparison with that of SYFO and SFO electrolyte supported cells. UV-vis diffused spectroscopy explains the semiconducting nature of the prepared materials due to the existence of optical bandgap in the semiconductor region. The further investigation also verifies the protonic conduction of SLFO membrane by constructing oxygen ion blocking fuel cell with configuration of Ni-NCAL/BZCY/SLFO/BZCY/Ni-NCAL having 427.94 mW/Cm 2 fuel cell performance with 1.03 OCV at 550 °C temperature.
危险品化学品经营许可证（带存储）