In a statement, the Nobel committee said Gerhard Ertl was awarded "for his studies of chemical processes on solid surfaces."
The committee noted Ertl's work in determining the mechanisms at the molecular level, of the catalytic synthesis of ammonia over iron and the catalytic oxidation of carbon monoxide over palladium.
In 1998, Ertl won the Wolf Prize in Chemistry along with Gabor Somorjai of the University of California, Berkeley for "their outstanding contributions to the field of surface science.
Ertl works as professor emeritus at the Department of Physical Chemistry, Fritz-Haber-Institut der Max-Planck-Gesellschaft in Berlin.
The prize, which is to be formally awarded Dec. 10, carries a cash award of about $1.5 million.