IDIOM HELP NEEDED URGENTLY : 'Researched on'

[Pdgmat2010]

which one is correct and sounds better?
to me, both sound correct.

I researched on the domain and the possible implications that any IT implementation would have.

I researched about the domain and the possible implications that any IT implementation would have.

[magnus opus]

reasearch on is correct.

the scientists are crrently researching on Dolohin echolocation.

But the predicate of both the sentences is incorrect.

[Pdgmat2010]

thanks.
Could you tell me why you think the predicate of the sentence is wrong