Ruthenium(II) nitrosyl chloride monohydrate is primarily used in research and industrial applications due to its unique properties. It serves as a catalyst in various chemical reactions, particularly in organic synthesis, where it facilitates the formation of complex molecules. This compound is also employed in the study of nitric oxide (NO) chemistry, as it can release NO under specific conditions, making it valuable in biochemical and medical research related to NO signaling pathways. Additionally, it is utilized in the development of materials for electrochemical applications, such as sensors and energy storage devices, owing to its redox-active nature. Its role in photochemistry is also notable, where it is explored for light-induced reactions and potential use in solar energy conversion systems.