Nitrogen-doped yolk–shell carbon nanoparticles are one of the most promising functional nanomaterials for various potential applications because of their functionality and adaptability in both the hollow shells and yolks. Yolk–shell nanospheres are known for widely adopted template-based routes, which prove to be expensive and cumbersome and showed inadequate capability to build complex internal structures. Herein, a facile and controllable strategy for fabricating nitrogen-doped yolk–shell carbon nanospheres was proposed through a simple leaching process. The production of the yolk–shell structure is based on the selective dissolution of inhomogeneous solid polymer nanospheres using methanol as leaching agent. The yolk sizes of the nanospheres can be controlled in the range 110–360 nm by simply varying the number of leaching times. In particular, results of the electrochemical properties of the prepared nanospheres with different yolk size suggest that the optimal yolk–shell nanospheres with a yolk size of ∼230 nm delivered the best cycling performance and good capacity retention of 582 mAh g–1 at 1 C after 200 cycles. We believe that the proposed strategy will play a crucial role in energy storage application.

Functionalized carbon nanorods have attracted extensive attention in materials science and technology, due to their unique structure and excellent properties. Nevertheless, it remains a huge challenge to develop an approach that combines simple, cost-effective implementation paths with outstanding target products. Herein, we propose a soft-template strategy to achieve directional preparation of one-dimensional (1D) “urechis unicinctus”-like nitrogen-doped porous carbon nanorods with abundant nitrogen content (8.35 wt %), high surface area (2560 m2/g), and hierarchical pore structure. The anionic surfactant sodium bis­(2-ethylhexyl) sulfosuccinate (AOT) and melamine are the template agent and main carbon–nitrogen precursor, respectively. By controlling the amount of ammonia (NH4OH), the behavior of AOT molecules in the aqueous phase can be accurately interfered to construct rodlike micellar templates, thereby guiding the preparation of target structural products. The rationality and stability of the original route were verified by the rigorous control experiments and relevant characterization. Moreover, the prepared materials show excellent performance in the evaluation of supercapacitors with an outstanding specific capacitance of 398 F/g at a current density of 0.5 A/g and 73.4% of original specific capacitance retention at a current density of 20 A/g.

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