4793
Enhancing the photocatalytic activity of anatase TiO2 by improving the specific facet - induced spontaneous separation of photogenerated electrons and holes .
 Chemical: TiO2
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: TiO2