I have a question about diodes and the PN junction

[Etherealist]

Is the PN junction inside a diode what makes the electrical current only flow in one direction and not in the opposite direction? If this is so, why does it happen?
Also
Why is the P-type material said to have empty holes and the N-type material to have free electrons?

 

[berkeman]

Is the PN junction inside a diode what makes the electrical current only flow in one direction and not in the opposite direction?

Yes.

If this is so, why does it happen?

What have you found so far in your Google searching? There are a lot of resources on the net that explain this. What is your background in EE and solid state physics? The level of our replies will depend on your reading so far and your background, so we can try to do our best in our replies. Thanks.

 

[DaveE]

There is a good set of lectures here:
https://www.khanacademy.org/science...onductors-class-12-india-physics-khan-academy