MoS2 nanoflakes-coated electrospun carbon nanofibers for “rocking-chair” capacitive deionization

Abstract

Developing highly efficient electrical-driven desalination techniques with minimum energy consumption and high stability is urgently required to settle the global water shortage. Herein, MoS2 nanoflakes-coated carbon nanofibers (CNFs@MoS2) are synthesized via electrospinning and subsequent hydrothermal reaction. The CNFs@MoS2 shows excellent dual-mode capacitive performance, and the CNFs@MoS2-based RCDI exhibits excellent desalination performances (desalination capacity: 53.03 mg g−1; desalination rate: 0.157 mg g−1 s−1) with good long-term stability (11.2% reduction in 30 cycles). The superior desalination performance should be ascribed to the dual-mode capacitive behavior of the CNFs@MoS2 and the rational cell architecture (the ion intercalation/deintercalation capacity of “rocking-chair” capacitive deionization is more balanced than that of the asymmetrical cells like hybrid capacitive deionization). This study is interesting since it exemplifies the critical importance of both dual-mode capacitance electrode materials and rational cell architecture, which could cast light on the further development of high-efficiency electrochemical desalination systems.