28521
With an ordered polystyrene ( PS ) template - assisted electrochemical approach we synthesized three - dimensional ordered macroporous ( 3DOM ) Cu2O / Ni inverse opals as electrodes for supercapacitors .
 polystyrene, Cu2O, Ni
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 polystyrene, Cu2O, Ni