Preparation of copper ion doped strontium zirconate and its infrared emission characteristics

Cu2+ doped SrZrO3 (SrZr1-xCuxO3, x = 0, 0.01, 0.03, 0.05 and 0.07) perovskite powders were prepared by sol-gel method with Zr(NO3)4·5H2O, Sr(NO3)2 and Cu(NO3)2·2.5H2O as raw material. The influence of the ratio of metal ion to citric acid, pH value, and calcination temperature on the synthesis of high-purity SrZrO3 powder and the infrared emissivity characteristics of the synthesized material was systematically studied. XRD, XPS, FT-IR and dual-band emittance measuring instrument were used to study the phase composition, microstructure of the sample and the effect of copper ion doping on the infrared emittance of SrZrO3 at 3–5 μm. The results show that the infrared emissivity of SrZrO3 doped with Cu2+ is lower than that of SrZrO3. When x = 0.03, the infrared emissivity at room temperature of 3∼5 μm reaches the lowest value of 0.4259. With the increase of temperature and time, SrZr1-xCuxO3 showed better thermal infrared properties, and the samples all showed weak thermal infrared intensity, and the surface temperature was lower than the background temperature and relatively stable. These findings suggest that Cu2+-doped SrZrO3 holds great potential as a promising candidate material for infrared stealth applications.