Can hydrocarbon help to split molecular hydrogen into atoms?

I am a physicist and have the following chemistry problem. 
When a sample is exposed to H2 (molecular hydrogen), a tiny amount of atomic hydrogen or, maybe, protons is generated. Extremely small amount but exceeding the thermally generated amount by many orders of magnitude. The origin can be traced to the ever existing surface contamination by hydrocarbons and water (monolayer). They somehow help to generate protons/atomic hydrogen on the surface.
Any tips?
Thanks, 
Hengan


PS It can be H+ from adsorbed water, too, but why molecular hydrogen is then needed? 


Sample: Graphite in a hydrogen atmosphere at room temperature. The graphite has probably some remnants of PMMA from processing plus it was exposed long enough to ambient atmosphere and, hence, adsorbed water and other ambient polymers (standard contamination layer of nanometer thickness). 


