Topochemical synthesis of two-dimensional molybdenum carbide (Mo2C) via Na2CO3-Assited carbothermal reduction of 2H–MoS2

Abstract

Due to its promising applications on catalysis, electronics and electrochemical energy storage, 2D Mo2C has emerged as an important member in the 2D family. Herein, an efficient and high-yield method was proposed for the preparation of ultra-thin 2D Mo2C via Na2CO3-assited carbothermal reduction of 2H–MoS2. It was found that 2H–MoS2 can be completely carbonized to Mo2C at a MoS2:Na2CO3:C molar ratio of 2:4.2:11 at 850 °C for 2 h. Meanwhile, the prepared Mo2C were intercalated by the co-product Na2S. After leaching treatment with deionized water, the intercalated Na2S was removed and high crystalline 2D Mo2C were successfully prepared. Furthermore, the addition of Na2CO3 as a desulfurizer can greatly promote the carburization and exfoliation rates of 2H–MoS2. As can be seen from the FE-SEM images, the prepared Mo2C has a pretty regular layered structure with the layer thickness of 5–15 nm.