Even if Black Zetsu, whose Chakra was already almost depleted, had tried to detonate himself, it would not have caused much damage, but it did indeed slow down Orochimaru's pace slightly.
By the time Orochimaru reappeared on the ground in a couple of blinks, Black Zetsu had already vanished from his original spot.
Orochimaru hastily placed his palms on the ground, sensing briefly to pinpoint Black Zetsu's approximate location.
Chapter 261