11080
Due to the desirable characteristics of BOMCs , BOMCs are highly active , cheap , and selective metal - free electrocatalysts for the oxygen reduction reaction ( ORR ) in alkaline solution .
 Chemical: oxygen
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: oxygen