Nickel Chelate Derived NiS₂ Decorated with Bifunctional Carbon: An Efficient Strategy to Promote Sodium Storage Performance

Abstract

The sodium storage performance of NiS 2 suffer from low initial coulombic efficiency and poor cycling stability which are ascribed to the volume expansion and collapse of the structure during the charge/ discharge transformation process. Compared with composites, encapsulating NiS 2 in carbon framework is more effective in buffering for the volume expansion and enhancing the electronic conductivity of sodium-ion batteries. In this work, NiS 2 decorated with bifunctional carbon (NiS 2 @C@C), where nickel dimethylglyoxime and polyaniline are employed as the precursor and carbon source, respectively, are obtained. Since the introduced carbon layer suppresses the volume expansion and enhances both the electronic conductivity and charge transfer of Na + , the attained NiS 2 @C@C displays outstanding sodium storage performance. At a current density of 0.1 A g −1 , a high reversible specific capacity of 580.8 mAh g −1 remains even after 100 cycles. The first coulombic efficiency (79.65%) and rate performance (448 mAh g −1 at 1.6 A g −1 ) of NiS 2 @C@C are also remarkable. Extraordinarily, the excogitation of NiS 2 decorated with bifunctional carbon is also significant for the preparation of similar materials.

Unlocking Few‐Layered Ternary Chalcogenides for High‐Performance Potassium‐Ion Storage

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Nickel sulfide nanocrystals on nitrogen-doped porous carbon nanotubes with high-efficiency electrocatalysis for room-temperature sodium-sulfur batteries

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A Selective Reduction Approach to Construct Robust Cu1.81S Truss Structures for High-Performance Sodium Storage

“…1 Sodium-ion batteries (SIBs) are considered a promising alternative for large-scale applications owing to their merits of natural abundance, low cost, and energy-storage mechanism similar to that of LIBs. 2,3 Among numerous anode materials for SIBs, transition metal sulfides (TMSs-e.g., Fe x S, Co x S, Ni x S, Cu x S) [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] have received great attention because of their high theoretical capacity based on a conversion reactions mechanism. [13][14][15][16] However, the conversion reactions usually cause huge volume changes upon sodiation/desodiation, which would inevitably pulverize the TMS electrodes and thus lead to fast capacity decay.…”