Self‐Assembly Film of Zeolite Y Nanocrystals Loading Palladium on an Au Electrode for Electrochemical Applications

Abstract

Nano-scale zeolite Y crystals were synthesized, and palladium nanoparticles were prepared in the supercage of the zeolite by "ship-in-a-bottle" approach. A novel method to fabricate zeolite-modified electrode (ZME) loading Pd nanoparticles was developed, in which the zeolite Y loading Pd 2þ ions was self-assembled on (3-mercaptopropyl) trimethoxysilane-attached Au surface to form the stable and density packed multilayers (SAM-ZME). The structures of zeolite Y and the SAM-ZME were investigated by using TEM, XRD and SEM techniques. Pd 2þ ions in the SAM-ZME were converted into Pd nanoparticles (Pd n 0 ) by two steps consisting of the electrochemical reduction as well as the succeeding admission and release of CO. The redox couple [Fe(CN) 6 ] 3À/4À was used to probe the electron-transfer barrier properties during self-assembling process. Moreover, the special properties of the SAM-ZME loading Pd n 0 were studied by using cyclic voltammetry and CO-probe in situ FTIR spectroscopy. The results illustrated that Pd n 0 in the SAM-ZME exhibits higher electrocatalytic activity for oxidation of adsorbed CO than that of ZME prepared in our previous study by zeolite coating method. The present study is of importance in design and preparation of SAM-ZME, which poccesseses excellent properties for the immobilization of electrocatalysts or biomolecules.

Electrocatalytic Oxidation of Formaldehyde onto Carbon Paste Electrode Modified with Nickel Decorated Nanoporous Cobalt‐Nickel Phosphate Molecular Sieve for Fuel Cell

“…The inclination of the base line for the voltammogram of VSB‐5/CPE and CoVSB‐5 electrodes can be attributed to the additional resistance obtained from the presence of VSB‐5 molecular sieves and the oxidation–reduction process of oxygen species in the molecular sieve layer 30. This inclination in baseline has been reported previously for all electrodes modified with aluminosilicate zeolites 30–32.…”

Electroanalytical Applications of Microporous Zeolites and Mesoporous (Organo)Silicas: Recent Trends

“…It was then reported that the application of pulsed voltage instead of dc voltage was likely to better control the amount of deposited zeolite from sub-monolayer to multilayer [63]. After a pioneering work on covalent attachment of zeolite particles to SnO 2 electrode via a silane coupling agent [64], some related strategies have recently appeared: the covalent self-assembly of zeolite particles on (3-mercaptopropyl)trimethoxysilane-attached gold surface and subsequent silanization of zeolite particles [65], or the controllable arrangement of zeolite/polyelectrolyte multilayers deposited on indium-tinoxide (ITO) electrode by the layer-by-layer (LBL) assembly technique [66,67]. An alternative coupling more or less these two approaches is the silanization of a gold surface with (3-mercaptopropyl)trimethoxysilane, hydrolysis and exposition of this monolayer to a cationic polymer and final contact with zeolites that are immobilized on the polymer film by favorable electrostatic interactions [68].…”

Reactive Deposition of Palladium Nanoparticles onto Zeolite Membranes in Supercritical CO2

“…In the viewpoint of practical applications, more benefits would be expected for Pd-loaded zeolite films and membranes. As a typical example, the film of zeolite-Y loading Pd nanoparticles fabricated via self-assembly on the (3-mercaptopropyl)trimethoxysilane-modified Au electrode exhibited higher electrocatalytic activity for oxidation of adsorbed CO than the pure zeolite-Y film . It has been well recognized that the Pd membranes possess the application potential for hydrogen-selective separation processes. − The thin membranes of Pd-loaded zeolites with selective permeability to hydrogen should be advantageous to intensify a hydrogen-related catalytic reaction in the membrane reactor. , …”

“…The fabrication of Pd-loaded zeolite membranes can be performed through self-assembling postsynthetic Pd-loaded zeolite crystals . However, the membranes synthesized as such may contain large crystal boundaries, resulting in low separation efficiencies .…”