Synergetic enhancement of electrical conductivity and infrared emissivity of SiC-MoSi₂ ceramics via N doping

N-doped SiC-MoSi2 ceramics were successfully fabricated by hot pressing in N-2 using Y(NO3)(3).6 H2O as both sintering aids and additional N sources. The impact of Y(NO3)(3).6 H2O content on the densification, electrical properties, and infrared emission performance of the resulting ceramics were investigated. The distribution of Y based sintering aid is improved by melting of Y(NO3)(3).6 H2O during slurry drying, enabling the relative density to increase up to 97.4%. Y(NO3)(3).6 H2O subsequently decomposes during sintering and allows the substitution of atomic N for the C sites in SiC lattice and production of the N-derived donor level. A larger amount of N dopant elevates the carrier density up to 1.90 x 1016 cm(-3). Remarkably, The SiC 10 wt% MoSi2 ceramics sintered with 16.9 wt% Y(NO3)(3).6 H2O exhibits the lowest electrical resistivity (0.791 omega.cm at room temperature) and highest infrared emissivity (0.913 at 800 ?), the latter of which may also be attributed to lattice distortion induced by N doping. This work demonstrates N doping as a prospective strategy for synergistically optimizing the electrical conduction and infrared emission performance of SiC-based ceramics for infrared source applications.