A Powerful One‐Step Puffing Carbonization Method for Construction of Versatile Carbon Composites with High‐Efficiency Energy Storage

Abstract Carbon materials play a critical role in the advancement of electrochemical energy storage and conversion. Currently, it is still a great challenge to fabricate versatile carbon‐based composites with controlled morphology, adjustable dimension, and tunable composition by a one‐step synthesis process. In this work, a powerful one‐step maltose‐based puffing carbonization technology is reported to construct multiscale carbon‐based composites on large scale. A quantity of composite examples (e.g., carbon/metal oxides, carbon/metal nitrides, carbon/metal carbides, carbon/metal sulfides, carbon/metals, metal/semiconductors, carbon/carbons) are prepared and demonstrated with required properties. These well‐designed composites show advantages of large porosity, hierarchical porous structure, high conductivity, tunable components, and proportion. The formation mechanism of versatile carbon composites is attributed to the puffing‐carbonization of maltose plus in situ carbothermal reaction between maltose and precursors. As a representative example, Li₂S is in situ implanted into a hierarchical porous cross‐linked puffed carbon (CPC) matrix to verify its application in lithium–sulfur batteries. The designed S‐doped CPC/Li₂S cathode shows superior electrochemical performance with higher rate capacity (621 mAh g^–1 at 2 C), smaller polarization and enhanced long‐term cycles as compared to other counterparts. The research provides a general way for the construction of multifunctional component‐adjustable carbon composites for advanced energy storage and conversion.