Construction of 1T-MoSe2 /TiC@C Branch-Core Arrays as Advanced Anodes for Enhanced Sodium Ion Storage

ChemSusChem. 2020 Mar 20;13(6):1575-1581. doi: 10.1002/cssc.201902565. Epub 2019 Nov 14.

Abstract

The use of active sites and reaction kinetics of MoSe2 anodes for sodium ion batteries (SIBs) are highly related to the phase components (1T and 2H phases) and electrode architecture. This study concerns the design and fabrication of wrinkled 1T-MoSe2 nanoflakes anchored on highly conductive TiC@C nanorods to form 1T-MoSe2 /TiC@C branch-core arrays by a powerful chemical vapor deposition (CVD)-solvothermal method. The 1T-MoSe2 branch can be easily transformed into its 2H-MoSe2 counterpart after a facile annealing process. In comparison to 2H-MoSe2 , 1T-MoSe2 has larger interlayer spacing and higher electronic conductivity, which are beneficial for the acceleration of reaction kinetics and capacity improvement. In addition, direct growth of 1T-MoSe2 nanoflakes on the TiC@C skeleton not only enhance the electrical conductivity, but also contribute to reinforced structural stability. Accordingly, 1T-MoSe2 /TiC@C branch-core arrays are demonstrated with higher capacity and better rate performance (184 mAh g-1 at 10 A g-1 ) and impressive durability over 500 cycles with a capacity retention of approximately 91.8 %. This phase modulation plus branch-core design provides a general method for the synthesis of other high-performance electrode materials for application in electrochemical energy storage.

Keywords: MoSe2; batteries; chalcogenides; electrodes; sodium-ion battery.