With electricity prices rising everyday, homeowners are looking for alternative means of powering their homes. Solar panels are on the top of everyone's list, but there still pretty expensive. But there's a DIY solution that could possibly give you some extra juice (albeit, in very small quantities). It's called a solar cell, and this video shows you how to make and test a solar cell using a sheet of copper.
These solar cells are basically sheets of copper with a layer of cuprous oxide (Cu2O) on them. The cuprous oxide is a semiconductor. You won't get much electricity from it, and in fact you'd need acres of these to power a home, but it's fun to make!
Start by cleaning the copper sheet. The cleaner the better. Then heat it on a red hot stove element or in a flame. This creates a thin layer of reddish cuprous oxide (or copper oxide) followed by a thicker layer of black cupric oxide. Cook it for about a half hour to get the black layer really thick. Then let it cool slowly. As it cools, most of the black layer flakes off, leaving only the red cuprous oxide layer.
To test, get a clear container of salty water. Put your solar cell inside, near one side, with some of it above the water for connecting a test lead. Put a plain sheet of copper inside, near the other side. Scrape off a little of the cuprous oxide from the solar cell and connect it to the positive test lead of your ammeter. Connect the negative test lead to the plain sheet of copper. The current will be in microamps.