6933
Hydrogen evolution from Pt / Ru - coated p - type WSe2 photocathodes .
 Chemical: Hydrogen; Chemical: Pt; Chemical: Ru
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: Hydrogen, Pt, Ru 
Answer:
 Chemical: Hydrogen; Chemical: Pt; Chemical: Ru