19146
Phase - controlled nickel sulfide ( Ni3 S4 and NiS1 . 03 ) nanoparticle ( NP ) / nitrogen - doped graphene ( NG ) composites are prepared through a facile one - pot hydrothermal process .
 Chemical: nickel sulfide; Chemical: Ni3 S4; Chemical: NiS1 . 03; Chemical: nitrogen - doped 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: nickel sulfide; Chemical: Ni3 S4; Chemical: NiS1 . 03; Chemical: nitrogen - doped graphene