A Novel Type of Water Desalination Technology Using MoS2-Based Thin Films for Selective Ion Transport.

Molybdenum disulfide (MoS₂) is a widely studied transition metal dichalcogenide with a range of potential applications including next-generation electronics, hydrogen evolution, and catalysis. It can also be used as a thermoelectric, exploiting the Seebeck effect to generate an electric voltage in response to a temperature gradient. Additionally, lithium-intercalated MoS₂ is known to undergo a transition from the 2H to 1T phase. Together, these two properties make this material suitable as a novel desalination technology that relies on selective ion movement. To assess MoS₂’s capabilities for ion transport, two types of experiments were conducted. The first set of experiments investigated changes in electric potential resulting from dropwise contact of various salt solutions with an MoS₂ membrane. Droplet test data displayed abrupt changes in electric potential followed by an exponential decay representing ion movement over time. A second set of experiments measured ion concentration changes over time using an MoS2 film in contact with separated DI water and salt solutions. Significant changes in solution ion osmolarities were recorded after a duration of one week. Results are promising for future development of thermoelectric desalination, battery and medical technologies.