For AC @ 60Hz, I use 1N4002 or higher (rectifier for 1A - 100V reverse voltage - 0.8V forward voltage).
If you need up to 3A current, use 1N5402 or higher.
For higher frequencies @ 3A, use Schottky diodes1 1N5822 or higher series (lower forward voltage 0.52V) or 1N4934 fast recovery diodes (@1 A - 100V reverse voltage)