Front dynamics in the O2 + NH3 reaction on Rh(110) surfaces

BENJAMIN BORKENHAGEN,MATÍAS RAFTI, GERHARD LILIENKAMP, WINFRIED DAUM, AND RONALD IMBIHL

Hong Kong

Congreso; 8th LEEM/PEEM International meeting; 2012

Hong Kong University of Science & Technology, Hong Kong

Recent research on the O2 + NH3 reactions on Rh(110) focused on interface instabilities in thisbistable reaction system [1]. Since different adsorbate structures and changes in the surfaceanisotropy presumably play a central role in the mechanism of the front instabilities we studiedthis reaction system in the 10e-6 and 10e-5 mbar range with LEEM and micro-LEED. We identified the mixed coadsorbate phase c(2×4)-O,N and the c(2×6)-O phase in the bistable range. At higher temperatures we observed the formation of micrometer-sized islands. Within these islands structural transitions occur via fronts. These fronts are sensitive to the microscopic surface structure such as surface steps.