8491
( ii ) The predicted optical band gaps are around 2 . 1 eV ( 590 nm ) , thus having much better performance in the absorption of visible light compared with both binary oxides .
 Chemical: oxides
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: oxides