Methylammonium iodide is a chemical compound with the formula CH3NH3I. It consists of a methylammonium cation and an iodide anion. This compound is often studied for its role in the field of perovskite solar cells, where it is used as a precursor material to create thin films that can efficiently convert sunlight into electricity. In addition to its applications in solar energy, methylammonium iodide is also of interest in crystal growth and material science. Its unique properties, such as solubility and stability, make it a valuable component in various research areas, including optical devices and semiconductors.