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Highlights: Enhancing rate performance of cellulose-derived hard carbon anodes from the view of cellulose molecular, crystalline, and aggregation structure is explored. Relationship of storage sodium and rate performance according to theoretical calculation and characterization analysis is illustrated. Cellulose intrinsic microstructure, conversion relationship between the allotropes of cellulose, and the critical influences on cellulose-derived carbon structure are discussed. Cellulose-derived carbon is regarded as one of the most promising candidates for high-performance anode materials in sodium-ion batteries; however, its poor rate performance at higher current density remains a challenge to achieve high power density sodium-ion batteries. The present review comprehensively elucidates the structural characteristics of cellulose-based materials and cellulose-derived carbon materials, explores the limitations in enhancing rate performance arising from ion diffusion and electronic transfer at the level of cellulose-derived carbon materials, and proposes corresponding strategies to improve rate performance targeted at various precursors of cellulose-based materials. This review also presents an update on recent progress in cellulose-based materials and cellulose-derived carbon materials, with particular focuses on their molecular, crystalline, and aggregation structures. Furthermore, the relationship between storage sodium and rate performance the carbon materials is elucidated through theoretical calculations and characterization analyses. Finally, future perspectives regarding challenges and opportunities in the research field of cellulose-derived carbon anodes are briefly highlighted. [ABSTRACT FROM AUTHOR]

Developing metal-free carbon electrocatalysts with atomically precise structures of hetero-doping is crucial for inventing reliable alternatives to precious metal-based catalysts. Our study reveals that the optimal active site is the edge-exposed N-neighbored carbon site in a chained N- C -C-S structure. Carbon material with N- C -C-S functional doping is controllably synthesized through polymer dehalogenation and heteroatom doping with thiomorpholine at room temperature. The resulting N/S-co-doped carbon with N- C -C-S functionalization, named N-C 2 -S, exhibits excellent ORR performance compared to other types of N, S-co-doped carbon, and commercial Pt/C. Typically, the N-C 2 -S sample shows the earliest onset potential of 0.96 V and a high half-wave potential of 0.85 V for promoting ORR. Assembled into an Al-air battery, The N-C 2 -S delivers an exceptional open-circuit voltage of 1.95 V and a large specific power of 128.1 mW cm 2. The synthesis strategy developed in this work can potentially open up precise functionalization of synthetic carbons with heteroatoms. [Display omitted] • The C site near the N in N-C-C-S is identified as highly active for oxygen reduction. • Different types of N, S-co-doped carbon are obtained via dehalogenation of PVDC. • N-C-C-S doping is realized via dehalogenation coupling reaction with thiomorpholine. • The N-C 2 -S sample exhibits exceptionally good oxygen reduction reaction performance. • The N-C 2 -S-assembled Al-air battery delivers high cell voltages and large powers. [ABSTRACT FROM AUTHOR]

Graphite phase carbon nitride (GCN) has shown promising prospects in diverse fields due to its exfoliating two-dimensional (2D) layered structure, adjustable electronic properties, wide absorption of visible light, and excellent chemical stability. It is crucial to accurately regulate and functionalize the intercalation space of 2D membrane materials for specific functions. Herein, we demonstrate the first GCN-based photothermal membrane for efficient solar steam generation. The polyoxovanadate anion was intercalated in between protonated GCN layers via an electrostatic interaction strategy, which enlarged the layer spacing up to ∼12.4 Å and increased the water and salt ions transport capability. Owing to the excellent photothermal conversion efficiency of polyoxovanadate, the polyoxovanadate-intercalated GCN membrane fabricated by suction filtration exhibited effective absorbance in full solar spectrum (>95.5 %) and achieved efficient solar steam generation (2.62 kg m−2 h−1 under 1 sun) when floating on water. The long-term durability test showed that the evaporation performance is stable and no salt precipitation observed. These findings not only expand the functional applications of carbon nitride materials, but also provide a new strategy for solar desalination. [Display omitted] • The insertion of V 15 between the GCN layers has extended the interlayer spacing up to ∼12.4 Å. • HCNV-80 membrane shows excellent photothermal conversion performance and achieves efficient solar steam generation. • The HCNV-80 membrane is stable and no salt precipitation is observed after long-term durability test. • HCNV-80 membrane has a variety of water transport channels, which is conducive to the rapid generation of water steam. [ABSTRACT FROM AUTHOR]