21031
The three factors work together , leading to superb electrochemical catalytic activities for both hydrazine oxidation ( its current generation ability is comparable to that of 10 wt % Pt - C catalyst ) and oxygen reduction ( its limiting current is comparable to that of 20 wt % Pt - C catalyst ) with four - electron transfer processes and excellent durability .
 hydrazine, Pt, C, oxygen, Pt, C
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 hydrazine, Pt, C, oxygen, Pt, C