I found below video at TED site on how to grow fresh air in your home and work area. The practical has been done and is proven to give adequate results. Also, you don't have to do much for living in an oxygen rich environment but to grow some very common plants inside your home/office building.

Actually, we have money plant at our home but that is outside the walls, so I will see how I can shift that in the house and take advantage.

PS: The unfortunate news is that we used to have all the three mentioned plants at our old house but left them there when we shifted in this new place :(

So guys, get them and Go Green...