12084
Such a synergistic effect successfully improves the power conversion efficiency ( PCE ) from 4 . 68 % ( reference cells ) to 6 . 11 % .
 None
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:  
Answer:
 None