Topological Insulator‐Assisted MoSe2/Bi2Se3 Heterostructure: Achieving Fast Reaction Kinetics Toward High Rate Sodium‐Ion Batteries. Issue 4 (20th January 2021)

• Record Type: Journal Article
• Authors: Li, Yu; Han, Manshu; Zhou, Zhihao; Xia, Xinhui; Chen, Qingguo; Chen, Minghua
• Is Part Of: ChemElectroChem. Volume 8:Issue 4(2021)
• Page Start: 697
• Page End: 704
• Publication Date: 2021-01-20
• Subjects: sodium-ion batteries -- heterostructures -- MoSe2 -- Bi2Se3 -- build-in electric field; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.202001409
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: Owing to the large interlayer spacing and the excellent theoretical capacity of MoSe2, it has great potential to be applied as an anode material for sodium‐ion batteries. However, the rate performance of MoSe2 is strongly limited by the insufficient intrinsic electron transfer kinetics. Herein, a simple two‐step hydrothermal method to construct MoSe2 /Bi2 Se3 heterostructures was developed by growing MoSe2 nanosheets onto Bi2 Se3 nanoflakes directly. The typical topological insulator possesses ultrafast surface electronic conductivity, which makes the batteries exhibit a superior rate capability and considerable cycling stability. At a high rate of 10 A g −1, the MoSe2 /Bi2 Se3 electrode still delivered a superior capacity of 244 mA h g −1 (about 60 % of the discharge capacity at 0.1 A g −1 ), which is better than that in some of the previously reported MoSe2 /carbon composites. It also can compare with some of the MoSe2 ‐containing complex sandwich architectures. Such unique rate performance is bound strongly with high interlayer spacing and rapid electron transfer kinetics. Besides, the different Fermi level energies of Bi2 Se3 (work function is 5.61 eV) and MoSe2 (work function is 4.3 eV) probably induce a built‐in electric field nearby the heterofaces. The electric force could promote Na ions diffusibility upon cycling, leading to high reversible capacity and excellent rate performance. Abstract : Better than bare : A hierarchical MoSe2 /Bi2 Se3 heterostructure is synthesized through a simple two‐step hydrothermal process. Owing to the high surface electronic conductivity of Bi2 Se3, large interlayer space of MoSe2, and built‐in electric field at the phase boundary, the heterostructure electrode presented superior rate capability and high surface‐controlled capacitive contribution compared with the bare MoSe2 and bare Bi2 Se3 electrodes.