Characterization of Potassium Catalysts Added as Koh to Carbon Surfaces

Potassium c a t a l y s t s a c t i v e toward g a s i f i c a t i o n o f carbon by 90 and CO2 can be generated by a d d i t i o n o f KOH t o carbon. We have cha rac te r i zed the c o n t r o l l e d a d d i t i o n o f KOH t o the edge sur face of g raph i te and the sur face o f a glassy carbon us ing AES, XPS and UPS. Submonolayer concentrat ions o f potassium-oxygen sur face species are formed from KOH on pre-ox id ized edge g raph i te and glassy carbon surfaces which are s t a b i l i z e d t o 8OO0C i n vacuum. These surfaces have two O(1S) peak envelopes centered near 531 eV and 533 eV. The higher b ind ing energy peak i s c h a r a c t e r i s t i c o f oxygen s t r o n g l y bound t o carbon. Heating t o 950' C r e s u l t s i n t h e l oss o f potassium and the lower b ind ing energy oxygen peak associated w i t h the p o t a s s i m c a t a l y s t . In cont r a s t the i n t e r a c t i o n o f KOH w i t h t h e a tomica l l y c lean edge g raph i te sur face does not produce the a c t i v e potassium form. The i n i t i a l oxygen content o f the carbon sur face i s impor tant i n c a t a l y s t p repara t i on from KOH.