Self-Standing Soft Carbon-Coated MoS2 Nanofiber Film Anode for Superior Potassium Storage

The poor electronic conductivity and large volume expansion effect of MoS2limit its application in potassium-ion batteries (PIBs). In addition to exploring effective modification methods, it is also necessary to build a new self-standing electrode system to improve its energy density. In this work, based on the potassium storage advantages and disadvantages of MoS2and carbon nanofibers, we have successfully prepared a self-standing soft carbon-coated MoS2nanofiber film electrode without any additives or metal collectors. As for the application in PIBs, it exhibits excellent rate performances (about 93 mA h g−1at the current density of 10 A g−1), and superior long-term cycling stability performances (a high-capacity retention of ~75% after 1800 cycles at the current density of 1 A g−1). The enhanced potassium storage performance can be attributed to the unique self-standing nanofiber film architectures.