Vokoun turned aside all 11 shots he saw in the final period as the Penguins were netting a pair of goals to break a scoreless tie. He turn in his third whitewash of the season, and second in two starts, for the streaking Penguins, who have won 15 straight games overall and 12 straight at home.
Vokoun, starting in place of the injured Marc-Andre Fleury, blanked Winnipeg 4-0 Thursday.
Matt Cooke tallied 8:10 into the third period and James Neal added an insurance tally for the Pens, who finished March 15-0 -- becoming the first NHL team to go undefeated in a calendar month with at least 10 games.
Evgeni Nabokov made 25 saves for the Islanders, whose three-game streak was broken.
The squad also announced defenseman Paul Martin will miss the rest of the regular season due to a broken bone in his wrist that will require surgery.