4086
It was found that the edge polar nature of the newly prepared EFGnPs without heteroatom doping into their basal plane played an important role in regulating the ORR efficiency with the electrocatalytic activity in the order of SGnP > CSGnP > CGnP > HGnP > pristine graphite .
 graphite
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 graphite