Development of a porous 304L Stainless steel substrate enhanced with graphene and platinum for hydrogen mitigation in passive autocatalytic recombiners

Abstract

The rapid expansion of the hydrogen economy poses significant safety challenges related to hydrogen handling across a wide range of applications. This study investigates the feasibility of using porous sintered 304 L stainless steel, coated with graphene and doped with platinum, as an advanced material for passive autocatalytic recombiners (PARs) to mitigate hydrogen release and improve operational safety. Detailed characterization using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy confirmed the uniform deposition of graphene and platinum layers, as well as structural features such as spinel phase segregation. The low surface wettability, attributed to the armchair configuration of graphene edges, further enhances the material’s suitability for catalytic recombination reactions in humid environments. Hydrogen removal tests demonstrated that an optimized platinum doping level of 0.5 wt% combined with a controlled substrate porosity of 50 µm resulted in a maximum hydrogen conversion efficiency of 40 %. These results highlight the critical influence of doping concentration and pore architecture on catalytic performance and overall PAR efficiency. Overall, this research provides valuable insights into the development of high-performance, passive hydrogen recombination systems, offering a promising pathway to improve safety and sustainability in emerging hydrogen technologies and to advance the hydrogen industry.