In-Situ Fourier Transform Infrared Spectroscopy (In-Situ FTIR) is an advanced analytical method used to investigate the chemical composition and molecular interactions of materials in real-time under controlled conditions, such as specific temperatures or atmospheres. It employs infrared light to probe the sample, measuring the vibrations of chemical bonds to produce a detailed spectrum. In-Situ FTIR is widely utilized in catalysis, materials science, and chemical engineering to study reaction mechanisms, surface interactions, and the evolution of species during processes like oxidation and reduction.