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Due to the unique nanohierarchy of multiple functional layers , the resultant 3D nanoforest of C / Sn / Ni / TMV1cys , binder - free composite electrode already and evenly assembled on a stainless steel current collector , exhibited supreme capacity utilization and cycling stability toward Na - ion storage and release .
 Chemical: C; Chemical: Sn; Chemical: Ni; Chemical: steel; Chemical: Na
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: C; Chemical: Sn; Chemical: Ni; Chemical: steel; Chemical: Na