Strongly Coupled 2D Transition Metal Chalcogenide-MXene-Carbonaceous Nanoribbon Heterostructures with Ultrafast Ion Transport for Boosting Sodium/Potassium Ions Storage

Abstract

Highlights Unique “Janus” interfacial assemble strategy of 2D MXene nanosheets was proposed firstly. Ternary heterostructure consisting of high capacity transitional metal chalcogenide, high conductive 2D MXene and N rich fungal carbonaceous matrix was achieved for larger radius Na/K ions storages. The highly accessible surfaces and interfaces of the strongly coupled 2D based ternary heterostructures provide superb surficial pseudocapacitive storages for both Na and K ions with low energy barriers was verified. Abstract Combining with the advantages of two-dimensional (2D) nanomaterials, MXenes have shown great potential in next generation rechargeable batteries. Similar with other 2D materials, MXenes generally suffer severe self-agglomeration, low capacity, and unsatisfied durability, particularly for larger sodium/potassium ions, compromising their practical values. In this work, a novel ternary heterostructure self-assembled from transition metal selenides (MSe, M = Cu, Ni, and Co), MXene nanosheets and N-rich carbonaceous nanoribbons (CNRibs) with ultrafast ion transport properties is designed for sluggish sodium-ion (SIB) and potassium-ion (PIB) batteries. Benefiting from the diverse chemical characteristics, the positively charged MSe anchored onto the electronegative hydroxy (–OH) functionalized MXene surfaces through electrostatic adsorption, while the fungal-derived CNRibs bonded with the other side of MXene through amino bridging and hydrogen bonds. This unique MXene-based heterostructure prevents the restacking of 2D materials, increases the intrinsic conductivity, and most importantly, provides ultrafast interfacial ion transport pathways and extra surficial and interfacial storage sites, and thus, boosts the high-rate storage performances in SIB and PIB applications. Both the quantitatively kinetic analysis and the density functional theory (DFT) calculations revealed that the interfacial ion transport is several orders higher than that of the pristine MXenes, which delivered much enhanced Na+ (536.3 mAh g−1@ 0.1 A g−1) and K+ (305.6 mAh g−1@ 1.0 A g−1 ) storage capabilities and excellent long-term cycling stability. Therefore, this work provides new insights into 2D materials engineering and low-cost, but kinetically sluggish post-Li batteries.

Modulating the Open-Circuit Voltage of Two-Dimensional MoB MBene Electrode via Specific Surface Chemistry for Na/K Ion Batteries: A First-Principles Study

“…In addition, the abundance of active sites on 2D electrode surfaces endows them with high theoretical capacities and desired ion mobilities. The theoretical capacity and ion-diffusion dynamics could be further improved by specific assembly technology to form a novel heterostructure. , To this end, numerous 2D materials such as graphene and graphene-based materials, − transition-metal dichalcogenides (TMDCs), − Ti 3 C 2 MXenes, − borophene, , and phosphorene , have been extensively studied as electrode materials for Na and K ion batteries. However, most 2D materials show low affinity toward Na and K ions, whose adsorption energy is typically smaller than 1.5 eV, − resulting in a low open-circuit voltage (OCV).…”

Perspectives on Working Voltage of Aqueous Supercapacitors

“…With the booming development of membrane technology, Janus membrane quickly solves the shortcoming of CEM single functionality and has been applied to separator for energy storage devices. [72,73] Janus membrane surface with the opposing properties in two sides, such as positive/negative charge, hydrophilic/hydrophobic, to name just a few. Liang et al [72] prepared an asymmetric supercapacitor in aqueous solution with a 2.2 V voltage, which consists of two activated carbon electrodes, Janus membrane as the separator (sulfonated polystyrene on the H 2 SO 4 side and quaternized polystyrene on the KOH side), 2 m KOH as negative electrolyte and 1 m H 2 SO 4 as positive electrolyte (Figure 5d).…”

Recent Research Progress in the Structure, Fabrication, and Application of MXene-Based Heterostructures

“…Integrating different materials to build heterostructures can combine their advantages and achieve synergistic effects. In one work, Cao et al [ 102 ] prepared a new self-assembled ternary heterostructure based on transition metal selenides, MXene nanosheets, and nitrogen-rich carbonaceous nanoribbons (CNRibs) with ultrafast ion transport properties for sodium and potassium-ion storage. This MXene-based ternary heterostructure could effectively prevent the re-stacking of 2D materials and increase the inherent conductivity.…”