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As a result of its high‐energy density, metal–selenides have demanded attention as a potential energy‐storage material. But they suffer from volume expansion, dissolved poly‐selenides and sluggish kinetics. Herein, utilizing' thermal selenization via the Kirkendall effect, microspheres of NiSe2 confined by carbon are successfully obtained from the self‐assembly of Ni‐precursor/PPy. The derived hierarchical hollow architecture increases the active defects for sodium storage, while the existing double N‐doped carbon layers significantly alleviate the volume swelling. As a result, it shows ultrafast rate capability, delivering a stable capacity of 374 mAh g−1, even after 3000 loops at 10.0 A g−1. These remarkable results may be ascribed to the NiOC bonds on the interface of NiSe2 and the carbon film, which leads to the faster transfer of ions, the effective trapping of poly‐selenide, and the highly reversible conversion reaction. The kinetic analysis of cyclic voltammetry (CV) demonstrates that the electrochemical process is mainly dominated by pseudocapacitive behaviors. Supported by the results of electrochemical impedance spectroscopy (EIS), it is confirmed that the solid–electrolyte interface films are reversibly formed/decomposed during cycling. Given this, this elaborate work might open up a potential avenue for the rational design of metal‐sulfur/selenide anodes for advanced battery systems. Hierarchial hollow‐structured NiSe2/N‐C with double carbon films are designed from the self‐assembled clew‐like Ni‐Pr by the Kirkendall effect. And it is found that incorporation of NiOC into the carbon layers enables tailoring of the interfacial traits, inducing the fascinating electrochemical behaviors. This elaborate work might open up a potential avenue for these rational TMDs anodes designs for advanced battery storage systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Na 2 THBQ were combined with CDs as cathode materials in SIBs for the first time. • o -Na 2 THBQ/CDs-2 performed good cycling stability and rate performance. • The mechanism of o -Na 2 THBQ/CDs-2 was explored by ex-situ tests. • The sodium ion diffusion coefficient of the materials was tested by GITT. Organic compounds are considered auspicious due to their widespread presence in nature, low cost, and sustainability. However, the inherent drawbacks of these organics' compounds, like low-conductivity and high-solubility, restrict their large-scale application. To solve these problems, we innovatively combined carbon quantum dots (CDs) with active substances (tetrahydroxybenzoquinone ortho -disodium salt (o -Na 2 THBQ)) at different mass ratios. The optimized o -Na 2 THBQ/CDs-2 (the mass ratio of o -Na 2 THBQ to CDs is 10:2) exhibited excellent electrochemical performance, the first-cycle discharge specific capacity was 410 mAh g−1 and maintained 182 mAh g−1 after 500 cycles, and the Coulombic efficiency was nearly 100 %. After 1300 cycles, the o -Na 2 THBQ/CDs-2 composite demonstrated a high specific capacity of 63 mAh g−1 at 500 mA g−1. This work provides a reference to design an optimal composite ratio of carbon dots (CDs) and organics to fabricate cathode materials for high-performance sodium-ion batteries. [ABSTRACT FROM AUTHOR]