Molecular Engineering on MoS₂ Enables Large Interlayers and Unlocked Basal Planes for High‐Performance Aqueous Zn‐Ion Storage

Abstract

Aqueous Zn‐storage behaviors of MoS2‐based cathodes mainly rely on the ion‐(de)intercalation at edge sites but are limited by the inactive basal plane. Herein, an in‐situ molecular engineering strategy in terms of structure defects manufacturing and O‐doping is proposed for MoS2 (designated as D‐MoS2‐O) to unlock the inert basal plane, expand the interlayer spacing (from 6.2 to 9.6 Å), and produce abundant 1T‐phase. The tailored D‐MoS2‐O with excellent hydrophilicity and high conductivity allows the 3D Zn2+ transport along both the ab plane and c‐axis, thus achieving the exceptional high rate capability. Zn2+ diffusion through the basal plane is verified by DFT computations. As a proof of concept, the wearable quasi‐solid‐state rechargeable Zn battery employing the D‐MoS2‐O cathode operates stably even under severe bending conditions, showing great application prospects. This work opens a new window for designing high‐performance layered cathode materials for aqueous Zn‐ion batteries.

Unexpected Role of the Interlayer “Dead Zn2+” in Strengthening the Nanostructures of VS2 Cathodes for High‐Performance Aqueous Zn‐Ion Storage

“…Generally, Zn‐ion tends to migrate from one hexagonal (H) site to another through the adjacent tetrahedral (T) site, [ 27,35 ] and the corresponding migration barrier is only 0.29 eV. This value is much lower than those of the reported Zn‐host materials, [ 15,21,35,44 ] demonstrating the facile Zn‐ion transportation in the VS 2 nanospheres. Density of states (DOS) are subsequently simulated (Figure 3h), the considerable states at Fermi level reveal the high electronic conductivity of the VS 2 nanospheres owing to its metallic 1T‐phase.…”

“…[8][9][10][11][12][13][14][15] Therefore, designing high-performance cathodes enabling the facile and stable Zn-ion transport is one of the key points to advance the ZIBs technologies toward a commercial prosperity.Layered materials such as vanadiumbased oxides and molybdenum disulfide (MoS 2 ) have been widely recognized as promising cathode candidates for aqueous ZIBs, benefiting from their convenient 2D Zn 2+ diffusion channels. [16][17][18][19][20][21][22] However, layered vanadium disulfide (VS 2 ), which combines the advantages of the above two materials in terms of the rich redox chemistry of vanadium and large interlayer spacing/ high electrical conductivity of transition metal dichalcogenides (TMDs), has not received popular interests. Furthermore, compared to the mainstream oxide cathode materials, VS 2 features weaker electrostatic interactions with divalent Zn 2+ due to the lower electronegativity of S 2− than that of O 2− , enabling the faster ion-diffusion kinetics.…”

Interfacial Kinetics Regulation of MoS2/Cu2Se Nanosheets toward Superior High‐Rate and Ultralong‐Lifespan Sodium‐Ion Half/Full Batteries

“…[31] For the S 2p spectrum (Figure 1f), the signals of S 2p 1/2 (163.2 eV) and S 2p 3/2 (162 eV) are clearly detected. [32,33] The morphology and microstructure of MoS 2 /Cu 2 Se are tested: as shown in Figure 2a,b, as-prepared MoS 2 /Cu 2 Se still maintains the morphology of laminated square-nanosheets after the selenization treatment, and the size does not change (Figure 2c). The classic two-dimensional nanosheet structure (Figure 2d) often owns excellent high-rate performance due to its considerable specific surface area and abundant active sites.…”

A Kinetically Superior Rechargeable Zinc‐Air Battery Derived from Efficient Electroseparation of Zinc, Lead, and Copper in Concentrated Solutions

“…Compared to lithium-ion batteries, Zn batteries are considered as the next generation of anode alternatives due to their high theoretical capacity (820 mAh g À 1 ), abundance, [23] environmental impact (nontoxicity) [24,25] and compatibility with water or organic electrolytes, [24,25] driving the boom of Zn battery research. [26,27] In this context, the research on the electrodeposition of Zn has been a hot topic in recent years.…”