Fractal analysis of surface geometry effects on catalytic reactions

Abstract

Abstract We study the effects of the surface morphology of catalysts on their performance. The surface geometry parameter is varied by taking surfaces of different fractal dimensions. The reaction mechanisms studied are the Eley-Rideal process (diffusion controled) and some modifications of it (chemically controled and side-reaction of the reactant). Theory predicts B(t) = Kt3−D/2 were B(t) is the amount reacted after time t, D is the surface fractal dimension, and K is a collection of constants. In a detailed simulation study we verified the theoretical prediction and were able to retrieve not only D, but, for the first time also K. Conditions under which an increase in surface roughness can either enhance or quench the efficiency of the catalytic reaction are identified and explained.