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Graphene ' s success has shown that it is possible to create stable , single and few - atom - thick layers of van der Waals materials , and also that these materials can exhibit fascinating and technologically useful properties .
 Chemical: Graphene
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