Carbon is a simple, stable and popular element with many allotropes. The carbon family members include carbon dots, carbon nanotubes, carbon fibers, graphene, graphite, graphdiyne and hard carbon, etc. They can be divided into different dimensions, and their structures can be open and porous. Moreover, it is very interesting to dope them with other elements (metal or non‐metal) or hybridize them with other materials to form composites. The elemental and structural characteristics offer us to explore their applications in energy, environment, bioscience, medicine, electronics and others. Among them, energy storage and conversion are extremely attractive, as advances in this area may improve our life quality and environment. Some energy devices will be included herein, such as lithium‐ion batteries, lithium sulfur batteries, sodium‐ion batteries, potassium‐ion batteries, dual ion batteries, electrochemical capacitors, and others. Additionally, carbon‐based electrocatalysts are also studied in hydrogen evolution reaction and carbon dioxide reduction reaction. However, there are still many challenges in the design and preparation of electrode and electrocatalytic materials. The research related to carbon materials for energy storage and conversion is extremely active, and this has motivated us to contribute with a roadmap on ‘Carbon Materials in Energy Storage and Conversion’.

Emerging trends in anion storage materials are reviewed, focusing on the classification, storage mechanisms, and electrochemical features of anion storage materials in various electrolytes for electrochemical capacitors in a symmetric or hybrid manner.

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.201803444. Electrochemical sodium storage and capture are considered an attractive technology owing to the natural abundance, low cost, safety, and cleanness of sodium, and the higher efficiency of the electrochemical system compared to fossil-fuel-based counterparts. Considering that the sodium-ion chemistry often largely deviates from the lithium-based one despite the physical and chemical similarities, the architecture and chemical structure of electrode materials should be designed for highly efficient sodium storage and capture technologies. Here, the rational design in the structure and chemistry of carbon materials for sodium-ion batteries (SIBs), sodium-ion capacitors (SICs), and capacitive deionization (CDI) applications is comprehensively reviewed. Types and features of carbon materials are classified into ordered and disordered carbons as well as nanodimensional and nanoporous carbons, covering the effect of synthesis parameters on the carbon structure and chemistry. The sodium storage mechanism and performance of these carbon materials are correlated with the key structural/chemical factors, including the interlayer spacing, crystallite size, porous characteristics, micro/nanostructure, morphology, surface chemistry, heteroatom incorporation, and hybridization. Finally, perspectives on current impediment and future research directions into the development of practical SIBs, SICs, and CDI are also provided. Nanostructured Carbon

Despite the clear benefits of Na and S active materials, Na− S hybrid energy storage devices have yet to be exploited, and existing Na−S batteries cannot provide fast kinetics and long-term stability. Herein, we describe chemical and electronic coupling of the redox-active organosulfur moiety (−S−S−S−) with carbon nanotube (CNT) networks for high power and long cyclability of Na−organosulfur hybrid energy storage devices. The facile and reversible surface redox kinetics of organosulfur-tethered CNT is associated with a two-electron transfer toward the formation of low-order polysulfide, as confirmed by in situ and ex situ analyses. The specific capacitance of SOS-OCNT is 377 F g −1 (94% of theoretical capacitance) and 61.3% of capacitance is retained at 10 A g −1 . The Na−organosulfur hybrid full cells deliver an ultrahigh power density of 13.4 kW kg −1 and high energy density of 27 Wh kg −1 over 50000 cycles.

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