27131
Here we report a stable , scalable design and molecular level fabrication strategy to create photoelectrochemically active heterostructure ( PAH ) units consisting of an efficient semiconductor light absorber in contact with oxidation and reduction electrocatalysts and otherwise protected by alumina .
 Chemical: alumina
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: alumina