화학공학소재연구정보센터
Applied Surface Science, Vol.493, 897-903, 2019
Uniform and reactive hydrogen polysilsesquioxane hollow spheres immobilized with silver nanoparticles for catalytic reduction of methylene blue
The facile synthesis of a new class of reactive hydrogen polysilsesquioxane (HPSQ, (HSiO1.5)(m)) hollow spheres is reported in this work. HPSQ hollow spheres can be controllably fabricated from triethoxysilane (TES, HSi(OEt)(3)) as a sole precursor through a polystyrene template-directed sol-gel process under aqueous acid-catalyzed conditions followed by template removal. The particle size and shell thickness of the spheres could be fine-tuned by utilizing different amounts of TES. Total preservation of Si-H bonds and formation of a Si-O-Si framework in the HPSQ hollow spheres are confirmed by FTIR and Si-29 NMR. Reactive Si-H moieties combined with a hollow structure make HPSQs suitable as carriers for noble metal nanoparticles. HPSQ hollow spheres function not only as a host that can adsorb Ag ions but also as a mild reducing agent for these ions. TEM studies show that the synthesized AgNPs are dispersed well on the HPSQ hollow spheres with an average particle size of 2-10 nm. XRD studies indicate that the resulting AgNPs are highly crystalline with a face-centered cubic geometry. SEM-EDS shows that the Ag content on the selected surface is 4.76 wt%. HPSQ hollow spheres loaded with AgNPs exhibit high performance when utilized as a catalyst to reduce methylene blue.