A simple way to prepare palladium nanoparticles decorated with cyclodextrins and ionic liquid. The effects of coating on the catalytic activity and colloidal stability

BRAVO, M. VIRGINIA; SILVA, O. FERNANDO; ADAM, CLAUDIA; GRANADOS, ALEJANDRO M.

JOURNAL OF MOLECULAR LIQUIDS

ELSEVIER SCIENCE BV

Año: 2020 vol. 304

0167-7322

In thiswork, palladiumnanoparticles (PdNps)were synthesized by reducing palladiumchloridewith sodiumborohydride(NaBH4) aqueous solutions in presence of organic capping ligands such as β-cyclodextrin (βCD), anamphiphilic imidazole-based Ionic Liquid (C12mimBr) and an amphiphilic βCD derivative (βCDMOD14). The resultsdemonstrated that the molecular organization of the capping agents has an important role in the stability ofcolloidal solution of PdNPs. In particular, the stability of PdNPs coatedwith βCDMOD14 (Pd@βCDMOD14) can becontrolled by changing the pH of the colloidal suspension. In addition, we propose that during the synthesis ofPdNps and capped with C12mimBr (Pd@C12mimBr), the source of palladium is a coordination complex formeddue to the presence of C12mimBr. Additionally, we studied the catalytic activity of Pd@βCDMOD14 and Pd@C12mimBr using the reduction reaction of aromatic nitro compounds to aromatic amine in the presence ofNaBH4, as a model in the remediation of aqueous phase. The kinetic data were modeled to the Langmuir?Hinshelwood equation that allows us to discriminate the affinity of 4-NP and NaBH4 towards modified surfaceof NPs in terms of their association constants (K4-NP, KBH4).