The poisoning of Pd–Y alloy membranes by carbon monoxide

We have explored the poisoning mechanism of CO on Pd–Y alloy membranes by means of thermal desorption spectroscopy (TDS) and X-ray photoelectron spectroscopy (XPS). TDS results show the total deuterium content sharply decreases and the desorption peak shifts to higher temperature with the increasing concentration of CO (from 0% to 26%) in gaseous deuterium. XPS results show that there are YO x , carbon, carbonate and adsorbed molecular CO on Pd–Y alloy surfaces after reaction with the mixture of D 2 + 26%CO at 623 K followed by cooling to room temperature. But no carbides and PdO x are detected.