Tubular Clay Nano-Straws in Ordered Mesoporous Particles Create Hierarchical Porosities Leading to Improved CO₂ Uptake

The use of solid adsorbents for CO2 capture is importance in the development technologies to remove this greenhouse gas. High surface area mesoporous materials are used encapsulate or functionalize amines that selectively CO2. MCM-41 class hexagonally ordered silicas have areas between 1000 and 1500 m2/g, which principle allows a significant degree when such as polyethyleneimine (PEI) encapsulated within pores occupy entire materials. However, tight 3 nm pore channels create challenge infiltration PEI throughout volume, resulting much lower uptake at high concentrations. This work describes introduction clay nanotubes (halloysite) with an inner diameter 15–30 into pellets mitigate diffusional restrictions. through one-step ship-in-a-bottle approach synthesis aerosol-assisted system where synthesized droplets containing halloysite. morphology composite material several extend from interior protrude pellet like straws. These ceramic 0.5–2 μm length, their lumen ranges 15 30 nm, thus providing improved entry pathway molecules access pellets. concept enhance loading MCM-41, leads increase levels. composites halloysite nano-straws (MCM-41/HNT) show doubling levels (7.1 wt %) kinetics (k = 0.11 s–1) comparison sorbents (3.9 % k 0.05 50 loading. indicates potential validity improve coupling enhanced molecular transport material. generality further applications adsorption catalysis.