How to Make a Solar Panel?
Normally, solar panels are manufactured out of silicon, a semiconductor. The process of purifying silicon, however, is very costly. The good news is that silicon is not the only material or semiconductor that displays a photoelectric effect, there are other metal compounds that show the photoelectric effect too. Cuprous oxide is a well known semiconductor which has been in use even before the advent of silicon as a semiconductor. So how is making solar panels possible without silicon? The clever use of cuprous oxide in place of silicon does the trick. The efficiency of cuprous oxide is much lower than silicon, but the cost of manufacture is comparatively negligible. So, what we do is, create a thin film of cuprous oxide over copper metal, and use it as a solar cell. The procedure for creating this thin film of cuprous oxide is to literally burn copper in air, creating a layer of cuprous and cupric oxide over it. You will need a very high wattage (1000 watts or more) electric coil type heater with a wide base. Buy a square piece of copper flashing of such a size, that it is lesser than the coil diameter, and fits inside it. Scrub the plate thoroughly with sandpaper and clean it. The procedure then starts with heating the square plate. You will see a beautiful potpourri of oxidation patterns forming on the plate after a sufficiently high temperature is reached. The color will change from pinkish red to then brown, and ultimately black as you go on heating it. The black layer that forms is cupric oxide (CuO) and below that, the reddish layer formed is cuprous oxide (Cu2O). The red film is what we are interested in. The black layer is more like soot that can be cleared off carefully after cooling. Once the surface is sufficiently black, stop heating and let the copper plate cool. As it cools, the copper plate contracts differentially, that is unequally, and therefore patches of the red pinkish layer is exposed. After the plate has totally cooled off, rinse it carefully and remove the black soot. Do not scrub the plate as it may remove the red cuprous oxide film too. Thus the main part of the procedure of building a solar panel is over. Cut the top of a large water bottle or can and place the oxidized sheet of copper in it. Let the oxidized film part face the outside of the bottle. Place another same sized piece of copper in the bottle, without letting the two plates touch each other. Fill the bottle with salt water till about 80% of the plates are submerged. Attach two crocodile clips to the plates, and connect the positive lead of a microammeter to the copper plate, and the negative lead to the oxide coated plate. Keep the whole apparatus in the Sun. As you place it in the Sun, you will see the ammeter reading going up. This shows that there is current flowing through the apparatus and you have succeeded in making a solar cell! This cell can give you an approximate power output of around 10 microwatts. It is not sufficient for lighting even a bulb but its a start! Thus you can make your own solar panel at home and enjoy the process of creating something new! This method is not
feasible for commercial production currently, but shows an alternative to silicon as a solar cell. In future, an advanced form of this method may make cheap and affordable solar cells possible!