catalystsupport

A catalyst support is a material that carries and disperses the active catalytic species in heterogeneous catalysis. The support provides a high surface area, porous structure, and mechanical stability to enhance the accessibility of active sites, improve dispersion, and reduce sintering or leaching of the active phase during reaction conditions. Supports can also influence the catalyst’s electronic properties and acid–base characteristics, affecting activity, selectivity, and durability.

Common supports include oxide materials such as silica (SiO2), alumina (Al2O3), and titania (TiO2), which offer high surface areas and robust thermal stability; carbon-based materials like activated carbon, graphene, and carbon nanotubes, valued for electrical conductivity and tunable porosity; and structured materials such as zeolites and mesoporous silicas (e.g., MCM-41, SBA-15) that provide shape and size selectivity. Some supports also possess acidic or basic sites that interact with the active phase or reactants.

Preparation and design of catalyst supports involve methods such as impregnation or incipient wetness to load active metals, co-precipitation, and sol-gel procedures to tailor surface chemistry and porosity. Metal–support interactions, including SMSI (strong metal–support interactions), influence dispersion, particle size, and resistance to sintering.

Applications span broad areas of heterogeneous catalysis, including hydrogenation, oxidation, reforming, hydrodesulfurization, and environmental catalysis, as well as electrocatalysis and fuel-cell technologies where supports like carbon play a key role. Characterization typically covers surface area and porosity (BET), pore distribution, particle size (TEM/XRD), and surface composition (XPS/chemistry).

Challenges include thermal sintering, metal leaching, coking, and chemical degradation of the support, which can reduce activity and selectivity over time.