Solar panels are primarily made of silicon, not silicon dioxide. Silicon is a semiconductor material that is a key component in the manufacturing of photovoltaic (PV) cells, which are the building blocks of solar panels. Silicon is chosen for its semiconducting properties, making it an ideal material for converting sunlight into electricity through the photovoltaic effect.

Here’s a simplified overview of the process:

1. Silicon Wafers: The basic unit of a solar cell is a thin wafer typically made from crystalline silicon. These wafers are sliced from a larger ingot of purified silicon.
2. Doping: The silicon wafers are then doped with small amounts of other elements to create layers with different electrical properties. This process is crucial for forming the p-n junctions necessary for the photovoltaic effect.
3. Photovoltaic Effect: When sunlight strikes the silicon in the solar cell, it excites electrons, creating an electric current. The p-n junction facilitates the movement of these excited electrons, resulting in the generation of electricity.

Silicon dioxide (SiO2) is a compound that contains silicon and oxygen, commonly known as quartz or silica. While silicon is a key material in solar panels, silicon dioxide is not used as a direct component of the solar cell. However, silicon wafers can be coated or passivated with a thin layer of silicon dioxide to improve their performance and durability.

In summary, solar panels are made primarily of silicon, specifically in the form of silicon wafers, to harness the photovoltaic effect and convert sunlight into electricity.