Biomaterial Database

Coadsorption of hydrogen and CO on hydrogen pre-covered PtRu/Ru(0001) surface alloys. 2010

Thomas Diemant, and Joachim Bansmann, and Hubert Rauscher

Institute of Surface Chemistry and Catalysis, Ulm University, 89069 Ulm, Germany. thomas.diemant@uni-ulm.de

The influence of pre-adsorbed hydrogen on the adsorption of CO on well-defined PtRu/Ru(0001) surface alloys and the modification of the adsorption properties of both adsorbate species due to coadsorption was studied by a combination of temperature-programmed desorption and infrared spectroscopic measurements. The hydrogen binding strength is weakened both by surface alloy formation and by CO coadsorption. In the densely packed coadsorbate layers, which can be formed after CO post-adsorption, the adsorption properties of the adsorbed CO molecules are also affected significantly. Depending on the Pt surface concentration, the CO adsorption process on hydrogen pre-covered surfaces is blocked to a different extent with a decreasing blocking tendency for Pt-rich alloys.

UI	MeSH Term	Description	Entries
D010984	Platinum	A heavy, soft, whitish metal, resembling tin, with atomic number 78, atomic weight 195.084, symbol Pt. It is used in manufacturing equipment for laboratory and industrial use. It occurs as a black powder (platinum black) and as a spongy substance (spongy platinum) and may have been known in Pliny's time as "alutiae".	Platinum Black
D002248	Carbon Monoxide	Carbon monoxide (CO). A poisonous colorless, odorless, tasteless gas. It combines with hemoglobin to form carboxyhemoglobin, which has no oxygen carrying capacity. The resultant oxygen deprivation causes headache, dizziness, decreased pulse and respiratory rates, unconsciousness, and death. (From Merck Index, 11th ed)	Monoxide, Carbon
D006859	Hydrogen	The first chemical element in the periodic table with atomic symbol H, and atomic number 1. Protium (atomic weight 1) is by far the most common hydrogen isotope. Hydrogen also exists as the stable isotope DEUTERIUM (atomic weight 2) and the radioactive isotope TRITIUM (atomic weight 3). Hydrogen forms into a diatomic molecule at room temperature and appears as a highly flammable colorless and odorless gas.	Protium,Hydrogen-1
D000327	Adsorption	The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.	Adsorptions
D000497	Alloys	A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions.	Alloy
D012428	Ruthenium	A hard, brittle, grayish-white rare earth metal with an atomic symbol Ru, atomic number 44, and atomic weight 101.07. It is used as a catalyst and hardener for PLATINUM and PALLADIUM.
D013499	Surface Properties	Characteristics or attributes of the outer boundaries of objects, including molecules.	Properties, Surface,Property, Surface,Surface Property