18120
The high performance can be attributed to the unique structure : ( i ) the ultra - long MWCNT array facilitates fast electron transfer ; ( ii ) the tight adhesion between Co3O4 and MWCNTs prevents particle drifting and agglomeration ; ( iii ) the free space between MWCNTs promotes fast ion transport and alleviates the large volume variation during discharge - charge process .
 Chemical: Co3O4
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: Co3O4