PNNL

Abstract

Metal and metal oxide nanoparticles supported on high surface area materials are widely used in industry for fuel and chemical production and for environmental pollution control, but preventing nano-sized particle sintering has remained a great challenge. In this paper, we report that Ni-Cu alloy nanoparticles can be effectively stabilized in cubic mesostructured silica (SBA-16) following a conventional impregnation and thermal treatment process. The three-dimensional interconnected cage structure of the mesoporous SBA-16 allows good accessibility of reactant gas molecules to the metal nanoparticles and confines these particles within its nano-sized cages. This confinement hinders metal nanoparticle migration and sintering under harsh conditions. Based on this strategy, a new class of regenerable metal-based adsorbents which can remove sulfur impurities from warm syngas stream down to less than 60 parts per billion by volume (ppbv) is described. This same confinement strategy is expected to have impact for minimizing sintering or particle coarsening of nano-sized materials employed in other applications.