Hydrophilic MoS2/polydopamine (PDA) nanocomposites as the electrode for enhanced capacitive deionization

Because of its special architectures and excellent capacitive property, molybdenum disulfide (MoS 2 ) showed great potential in electrochemical-related applications. Nevertheless, the poor water wettability remains one of the primary weaknesses of MoS 2 for its application in capacitive deionization (CDI). In this work, MoS 2 was facilely modified by hydrophilic polydopamine (PDA) in a self-polymerization pathway to ameliorate the wettability of MoS 2 . With the soak time being carefully adjusted, MoS 2 modified by PDA for 4 h (MoS 2 /PDA-4) could exhibit not only lower inner resistances due to its better wettability, but also much higher specific capacitance because of the incorporation of electroactive PDA compared to original MoS 2 , resulting in the enhanced electrosorption rate (less than 9 min) and desalination capacity (14.80 mg/g). Moreover, the electrochemical stability of MoS 2 /PDA-4 guaranteed the nanocomposites a good regenerability. The results suggested the MoS 2 /PDA-4 electrodes a promising material for CDI device.