Mid-infrared transparent Y2O3-MgO composites with wide transmittance range and weak absorption peaks via the reduction of carbon contamination and agglomerations

Y 2 O 3 -MgO composites are promising for mid-infrared windows and domes in harsh environments. However, the insufficient transmittance range (the transmittance >30 % only in ∼2–7 μm) and strong absorption peak (the transmittance <32 % at 7.0 μm) of Y 2 O 3 -MgO composites severely limit their application range because of agglomerations and carbon contamination from organics in the raw materials, currently. In this study, utilizing carbon-free raw materials and high molecular motions, the reduction of carbon contamination and agglomerations within the as-synthesized nanopowers was achieved via the modified co-precipitation synthesis. A highly mid-infrared transparent (the maximum transmittance of 79 % at 6.0 μm) Y 2 O 3 -MgO composite with wide transmittance range (the transmittance >30 % in 2.2–9.7 μm) and weak absorption peaks (the transmittance ≈68.57 % at 7.0 μm) was fabricated by the hot-pressing sintering method using the as-obtained nanopowders in the absence of exogenous dopants. And the modified co-precipitation synthesis is a method with great potential for the development of mid-infrared transparent Y 2 O 3 -MgO composites with wide transmittance range and weak absorption peaks.