Synthesis and catalytic performance of highly dispersed platinum nanoparticles supported on alumina via supercritical fluid deposition

Highly dispersed platinum nanoparticles (NPs) supported on alumina were prepared by supercritical fluid deposition (SFD) with the aid of co-solvent ethanol using inorganometallic Na2PtCl6 center dot 6H(2)O as Pt precursor. The mean Pt particle size (1.5 nm) was obtained at the optimized deposition conditions of 40 degrees C and 110 bar and 3 h of deposition time. The catalysts were characterized by high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), CO diffuse reflectance infrared Fourier transform spectroscopy (CO-DRIFTS), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma optical emission spectrometry (ICP-OES) and hydrogen-oxygen titrations to investigate the structure-activity relationship. Compared with the catalyst prepared via an impregnation method, the Pt was highly dispersed to smaller particles for Pt/Al2O3 catalysts prepared by SFD and showed much higher catalytic activity of catalytic reforming of cyclohexane dehydrogenation. (C) 2020 Elsevier B.V. All rights reserved.