The regulator datasheet tells about the use of a schottky diode at the power output (1N5824).
Unfortunately, I cannot find this diode in the LCSC store.
On the Internet, I heard about an analogue of this diode - SS54.
Is it suitable for my purposes? Maybe someone connected this regulator with other diodes?
You need to look at the data sheets to see if it’s an equivalent in terms of current , voltage etc . The one you show is surface mount - do you really want that ?
I googled the diode of the data sheet and there are lot of hits for suppliers , so buy elsewhere ?
I fear your problems won't be over when you locate a suitable diode, because the PCB layout of a switching power supply is quite critical.
If you've never designed a switched mode power supply before, then you might be better off buying a ready built module.
When designing a high frequency switching regulated power supply, layout is very important. Using a good layout can solve many problems associated with these types of supplies. The problems due to a bad layout are often seen at high current levels and are usually more obvious at large input to output voltage differentials. Some of the main problems are loss of regulation at high output current and/or large input to output voltage differentials, excessive noise on the output and switch waveforms, and instability.
Loads of cheap LM2596 based buck-converters all over eBay. They use the adjustable output
voltage version with a 10-turn pot to set the output voltage. Some have an LED voltmeter
built in even.
The SS diode family are general purpose schottky diodes, SSxy being x amps at 10y volts,
so SS14 is 40V 1A, SS54 is 40V 5A, they are perfectly good choices, although I'm sure there
are devices with lower losses if you look.
As mentioned above, layout is crucial for a switch-mode power supply, careful control of
loop area in the high current paths is needed, although usually datasheets have a suggested
layout section you can just copy. Choice of inductor is also crucial, use an inadequate
part and the whole circuit can fail, or the inductor overheat.