4796
An optimal ratio of the oxidative { 001 } facets to the reductive { 101 } facets exists with regard to the photocatalysis of the faceted TiO ( 2 ) nanocrystals , and this is crucial for balancing the recombination and redox reaction rates of photogenerated electrons and holes .
 Chemical: TiO ( 2 )
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: TiO ( 2 )