Novel Designed MnS‐MoS₂ Heterostructure for Fast and Stable Li/Na Storage:Insights into the Advanced Mechanism Attributed to Phase Engineering

Abstract

Combining 2D MoS2 with other transition metal sulfide is a promising strategy to elevate its electrochemical performances. Herein, heterostructures constructed using MnS nanoparticles embedded in MoS2 nanosheets (denoted as MnS‐MoS2) are designed and synthesized as anode materials for lithium/sodium‐ion batteries via a facile one‐step hydrothermal method. Phase transition and built‐in electric field brought by the heterostructure enhance the Li/Na ion intercalation kinetics, elevate the charge transport, and accommodate the volume expansion. The sequential phase transitions from 2H to 3R of MoS2 and α to γ of MnS are revealed for the first time. As a result, the MnS‐MoS2 electrode delivers outstanding specific capacity (1246.2 mAh g−1 at 1 A g−1), excellent rate, and stable long‐term cycling stability (397.2 mAh g−1 maintained after 3000 cycles at 20 A g−1) in Li‐ion half‐cells. Superior cycling and rate performance are also presented in sodium half‐cells and Li/Na full cells, demonstrating a promising practical application of the MnS‐MoS2 electrode. This work is anticipated to afford an in‐depth comprehension of the heterostructure contribution in energy storage and illuminate a new perspective to construct binary transition metal sulfide anodes.

2D Material‐Based Heterostructures for Rechargeable Batteries

“…This is one to two orders of magnitude higher than that of bare MnS or MoS 2 , calculated from GITT results. [ 110 ] Besides, through ex situ electrochemical impedance spectroscopy (EIS) tests, MnS–MoS 2 heterostructures demonstrate the smallest resistance, corresponding to the best electrical conductivity. The built‐in electric field contributes to both increased electron transfer and elevated ion migration of the heterostructure.…”

Porous graphene-like MoS2/carbon hierarchies for high-performance pseudocapacitive sodium storage

“…4a, the Mo 3d spectrum for the bare MoS 2 can be fitted into three peaks at 232.7, 229.6 and 226.8 eV, corresponding to Mo 4+ 3d 3/2 , Mo 4+ 3d 5/2 and S 2s, respectively. 49 In contrast, the Mo 3d and S 2s peaks shift to higher binding energy with Δ E 1 = 0.2 eV and Δ E 3 = 0.3 eV, while two new peaks at 236.1 eV and 233.0 eV emerge, corresponding to Mo 6+ 3d 3/2 and Mo 6+ 3d 5/2 , which can be ascribed to the surface oxidation of few-layered MoS 2 . 50 To further confirm the chemical states of the surface component, XPS measurement after argon ion etching was performed (Fig.…”

Stable and Dendrite‐Free Lithium Metal Anodes Enabled by Ionic/Electronic Li2S/Mo Interlayer

“…The peak at 226.1 eV is S 2 s characteristic peak. [ 36,37 ] In Figure 2e, the peaks at 161.3 and 163 eV are ascribed to S 2 p 3/2 and S 2 p 1/2 for S 2− , respectively. After discharge to 0.01 V, the peaks of Mo 3 d 5/2 and 3 d 3/2 shift to 232.1 and 235.2 eV, indicating the phase transformation to 3 R phase (Figure 2d).…”