Rationalization of the Promotional Rules

Electrochemical promotion studies have used from the beginning5 7 two very simple qualitative rules in order to explain all the observed effects of varying potential Uwr or work function d on the reaction kinetics  

Increasing work function 0 (e.g. via addition of electronegative promoters) strengthens the chemisorptive bond of electron donor adsorbates (D) and weakens the chemisorptive bond of electron acceptor adsorbates (A). 

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