Answer: Silicon
Notes: The photovoltaic effect is employed by Solar Cells (or Photovoltaic Cells) to directly convert light energy into electricity. The most commonly used material for these cells is Silicon, including its mono-crystalline, polycrystalline, and amorphous varieties. While single-crystal silicon has a uniform molecular structure for efficient electron transfer, it must be "doped" with other elements to create an effective cell. Multi-crystalline silicon may be less efficient but is cheaper to produce. Amorphous silicon's ability to absorb 40 times more solar radiation renders it ideal for cost-efficient, building-integrated photovoltaic products.
