The win was the third straight for the Senators (20-18-1) in front of a record home crowd of 20,214 at Scotiabank Place. It was also Ottawa's second straight shutout over New York-based teams - the Senators blanked the Islanders 2-0 at Scotiabank Place on Wednesday night in front of 20,192, the previous attendance record.
Emery was in goal for both those games and has not allowed a goal in 141 minutes and 10 seconds.
The Rangers (18-17-4), who were shut out 2-0 by the Islanders on Tuesday, have lost seven straight games.
It took just 32 seconds for the Senators to take the lead as Alfredsson tipped a Chris Phillips point shot for his 10th goal of the season. Rangers netminder Henrik Lundqvist got a piece of the re-direct but the puck slowly squeezed through his pads and across the goal line.
That was the only blemish of the night for Lundqvist, who kept things close in the first and third periods. He stopped Alfredsson on a breakaway in the first period and then got his glove down to snag Alfredsson's rebound attempt.
Lundqvist finished with 27 saves.
Emery was at his best in the second period when the Senators were outshot 14-7, and also the second half of the third period when the Rangers pressed hard for the tying goal.
The Senators finished 0-3 on the power play while the Rangers went 0-6.
Notes: Josh Hennessey was recalled from the Binghamton Senators for the game to replace Mike Fisher, who suffered a knee injury against the New York Islanders on Wednesday night. ... The Senators are in Toronto on Saturday to face the Maple Leafs while the Rangers are home to face the Washington Capitals.