8608
In recent years , flexible devices based on nanoscale materials and structures have begun to emerge , exploiting semiconductor nanowires , graphene , and carbon nanotubes .
 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