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Graphene , a one - atom - thick two - dimensional ( 2D ) layer of sp ( 2 ) - bonded carbon , has received worldwide attention owing to its extraordinary physical and chemical properties .
 Chemical: Graphene; Chemical: carbon
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: Graphene; Chemical: carbon