Sacrificial Template Synthesis of Two-Dimensional Few-Layer MoSe₂ Coupled with Nitrogen-Doped Carbon Sheets for High-Performance Sodium Ion Hybrid Capacitors

Abstract

Molybdenum diselenide (MoSe2) is emerging as a promising anode material for sodium-ion hybrid capacitors (SIHCs) due to its high theoretical capacity. However, the limited rate capability and the poor stability restrain its practical applications. Herein, we report a template approach to prepare two-dimensional (2D) few-layer MoSe2 embedded in nitrogen-doped carbon sheets (MoSe2@NCS). Specifically, graphitic carbon nitride is in situ transformed as the sacrificial template, which not only inhibits the accumulation of the MoSe2 but also endows the MoSe2@NCS composite with a 2D morphology. Benefiting from this architecture, the heterostructure reveals the accelerated ion diffusion rate, enhanced electronic conductivity, and well-controlled volume expansion. Consequently, the MoSe2@NCS delivers a high specific capacity of 398.9 mAh g–1 at 0.1 A g–1 and a good rate performance of 229 mAh g–1 at 5 A g–1 . Meanwhile, an outstanding long cyclic stability with high capacity of 225.2 mAh g–1 is maintained after 1000 cycles at 1 A g–1. Hence, a SIHC based on the MoSe2@NCS anode is established and exhibits a high energy of 122.8 Wh kg–1 at 105 W kg–1 and power densities of 65.3 Wh kg–1 at 10500 W kg–1.

Exploring 2D Energy Storage Materials: Advances in Structure, Synthesis, Optimization Strategies, and Applications for Monovalent and Multivalent Metal‐Ion Hybrid Capacitors

“…Reproduced with permission. [ 412 ] Copyright 2021, American Chemical Society. g) Schematic illustration showing the synthetic procedure of NG@SnSe/C.…”

“…[370,411] For example, 2D few-layer MoSe 2 embedded in nitrogen doped carbon sheets (MoSe 2 @NCS) prepared by a template method was reported (Figure 24f). [412] This attractive 2D morphology and unique coupled structure inhibited the accumulation of MoSe 2 , promoted ion diffusion and enhanced electronic conductivity, thus endowing both MoSe 2 @NCS anode and MoSe 2 @NCS-based SIHC with superior electrochemical performance. Aiming to further enhance the rate capability and cyclic stability of MoSe 2 for SIHCs, the heterostructures constructed by MoSe 2 and various metal oxides have been proposed, [370,409,411,413] which may be the future development direction of MoSe 2 -based electrode materials for SIHCs.…”

“…f) Schematic illustration for the synthesis of MoSe 2 @NCS. Reproduced with permission [412]. Copyright 2021, American Chemical Society.…”

Facile Construction of Nano-Dimensional Bi Encapsulated in N-Doped Porous Carbon Frameworks for High-Performance Sodium-Ion Hybrid Capacitors

“…The SEM images (Figure a–c) present a 3D continuous porous network structure with microns of large pores, which is composed of cross-linked carbon nanosheets. The good electrical conductivity of carbon sheets is helpful to accelerate the Na + transmission rate . The TEM images (Figure d,e) of Bi@NPC-850-U further reveal that a large number of ultrafine bismuth NPs are completely and uniformly wrapped by the carbon layers.…”

Defect-Induced and Synergistic Na-Ion Storage Capability of TiO2(B)@MoSe2/Carbon Trinity for Ultrafast and Ultralong Cycling

“…The Mo 3d spectrum (Figure e) can be deconvoluted into six parts. The most distinct doublets at 228.9 and 232.0 eV belong to the Mo 3d 5/2 and Mo 3d 3/2 orbitals of Mo 4+ in MoSe 2 , respectively. − The two peaks at the binding energies of 235.8 and 230.6 eV can be assigned to the Mo–O–C and Mo–C bonds, respectively . The other two peaks at 233.1 and 229.0 eV are usually attributed to Mo–N bonds. , The Mo–N and Mo–C bonds cannot be observed from the Mo 3d spectra of pure MoSe 2 .…”