Secures part of Batman's outfit for picture (9)
I believe the answer is:
landscape
'picture' is the definition.
(landscape is a kind of picture)
'secures part of batman's outfit' is the wordplay.
'secures' becomes 'lands' (land can mean to obtain or secure).
'part of batman's outfit' becomes 'cape' (Batman wears a cape).
'lands'+'cape'='LANDSCAPE'
'for' is the link.
(Other definitions for landscape that I've seen before include "Expanse of scenery" , "Countryside for a painter" , "Painters may paint it" , "Oil perhaps" , "Art of laying out scenic grounds" .)