Review on High-Temperature Porous Media Materials for Clean Combustion of Hydrogen and Ammonia Fuels

ABSTRACT: Porous media combustion technology is regarded as one of the promising routes for efficient thermochemical conversion of hydrogen and ammonia fuels. However, porous skeletal materials are exposed to demanding service conditions including temperatures of 900–1500 °C, high-concentration water-vapor atmospheres, and frequent cyclic thermal shock, which can promote sintering, hydrothermal corrosion, oxidation, and thermomechanical fatigue cracking. Reviews addressing high-temperature material degradation, topological thermomechanical failure, manufacturing-induced defects and surface protection remain comparatively limited in the literature surveyed. In this work, four categories of high-temperature porous materials, i.e., oxide ceramics, non-oxide ceramics, silicate refractories and intermetallic compounds, are comprehensively reviewed. The thermomechanical failure mechanisms of conventional disordered structures and novel additively-manufactured ordered topologies (including triply periodic minimal surfaces, TPMS) under cyclic thermal shock are discussed based on thermal-shock-resistance figure-of-merit R. High-temperature micro-defects originating from replica impregnation, extrusion, and lithography-based ceramic manufacturing (LCM) additive manufacturing are analyzed. Special attention is paid to the hydrothermal-volatilization corrosion mechanism of SiC in water-vapor-rich atmosphere generated by ammonia combustion, together with the performance of multi-layer protective coatings including mullite, cordierite, Al₂O₃–Cr₂O₃ solid-solution and rare-earth silicate systems. A synergistic fuel-material-topology-coating selection matrix is proposed for hydrogen, ammonia and blended fuels. Finally, key bottlenecks and future research directions, covering composite ultra-refractory ceramics, self-healing environmental barrier coatings, high-temperature additive manufacturing, and catalytic-refractory integrated porous architectures, are put forward. This review aims to provide material-oriented references to support the development of porous media operating under the conditions of hydrogen–ammonia combustion.