Hydrogen Permeability of Composite Pd–Au/Pd–Cu Membranes and Methods for Their Preparation

Abstract

Thin Pd–40%Cu films were obtained via the classical melting and rolling method, magnetron sputtering, and modified with nanostructured functional coatings to intensify the process of hydrogen transportation. The films were modified by electrodeposition, according to the classical method of obtaining palladium black and “Pd–Au nanoflowers” with spherical and pentagonal particles, respectively. The experiment results demonstrated the highest catalytic activity (89.47 mA cm−2), good resistance to CO poisoning and long-term stability of Pd–40%Cu films with a pentagonal structured coating. The investigation of the developed membranes in the hydrogen transport processes in the temperature range of 25–300 °C also demonstrated high and stable fluxes of up to 475.28 mmol s−1 m−2 (deposited membranes) and 59.41 mmol s−1 m−2 (dense metal membranes), which were up to 1.5 higher, compared with membrane materials with classic niello. For all-metal modified membranes, the increase in flux was up to sevenfold, compared with a smooth membrane made of pure palladium, and for deposited films, this difference was manyfold. The membrane materials’ selectivity was also high, up to 4419. The developed strategy for modifying membrane materials with functional coatings of a fundamentally new complex geometry can shed new light on the development and fabrication of durable and highly selective palladium-based membranes for gas steam reformers.

Hydrogen Flux Inhibition of Pd-Ru Membranes under Exposure to NH3

“…Traditional hydrogen purification methods like pressure swing adsorption (PSA) have drawbacks such as high energy consumption, low hydrogen purity, and large foot-print area [8]. Hydrogen purification using Pd membranes 2 of 13 shows great potential in small-to medium-scale hydrogen production [9,10]. By integrating the NH 3 decomposition process with membrane purification in a single chamber [11,12], the separation and purification of hydrogen are realized while the decomposing reaction is conducted.…”

High-Performance Hydrogen-Selective Pd-Ag Membranes Modified with Pd-Pt Nanoparticles for Use in Steam Reforming Membrane Reactors

“…Therefore, pentagonally structured nanoparticles with a big number of high-energy facets are of major interest. The application of a modifier based on such nanoparticles to the surface of a palladium-containing membrane can significantly increase the catalytic activity of the material and the hydrogen permeability in low-temperature operation mode [54]. That is, the key factors contributing to the high activity of the material in reactions are the adjustment of the morphology and structure of particles (presence of high index facets, defects, and undercoordinated atoms) and the addition of a secondary metal [55][56][57][58][59].…”

A Commemorative Special Issue in Honor of Professor Victor Nikonenko

“…Polina Pushankina et al [ 9 ] obtained thin Pd-40%Cu films using the classical melting and rolling method and magnetron sputtering. The films were modified via electrodeposition according to the classical method of obtaining palladium black and “Pd-Au nanoflowers” with spherical and pentagonal particles, respectively.…”