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Graphical abstract Highlights • The interlayer distance of hard carbon crystallites is tunable. • The defect sites of hard carbon for Na-ion storage can be tunable. • The designed carbon anode exhibits an excellent electrochemistry property. • Na-ion full-cell delivers a high energy density of 247 Wh kg−1 (vs. anode). Abstract Hard carbon materials hold the most promising application among all anode materials for sodium-ion batteries because of the high storage capacity and good cycling stability. However, the low initial Coulombic efficiency limits their further commercialization. Herein, a new carbonization strategy is presented to prepare a cost-effective hard carbon material as anodes for sodium-ion batteries by pyrolyzing the interpenetrating polymer networks (IPNs) made from the mixture of biomass-derivative lignin and epoxy resin. By adjusting heat-treatment temperatures and the lignin/epoxy resin mass ratios, we can adjust the interlayer distance of carbon crystallites and defect sites for Sodium-ion storage, and thus obtain a hard carbon with a high capacity of 316 mAh g−1, a high ICE of 82%, and good rate capability (e.g. , 161 mAh g−1 at 300 mA g−1), all of which are superior to or comparable to those state-of-the-art carbons reported in literatures, by the help of a large interlayer distance of 3.95 Å. Besides, a full cell with the configuration of as-prepared hard carbon anode versus air-stable O3-Na 0.9 [Cu 0.22 Fe 0.30 Mn 0.48 ]O 2 cathode is further demonstrated, while it presents a high ICE of 80% and an energy density of 247 Wh kg anode −1 (vs. hard carbon) with good cycle performance. These excellent properties verify that our synthetic strategy is feasible, scalable and can be extended into the fabrication of various carbon anode materials with anticipative microstructures for the economical SIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • MIL-88B(Fe)/Fe 3 S 4 hybrids for effective water treatment by heterogeneous electro-Fenton. • Hybrid catalyst: highly uniform composition due to excellent distribution of small Fe 3 S 4. • Sulfidation allows breaking the activity-stability trade-off for high performance HEF. • Good recyclability of hybrids and fast trimethoprim removal even in urban wastewater. • Great catalytic activity and degradation mechanism confirmed by DFT calculations. Fe-based metal–organic frameworks are promising catalysts for water treatment, although their viability is hampered by the slow regeneration of active Fe(II) sites. A facile sulfidation strategy is proposed to boost the catalytic activity of MIL-88B(Fe) in heterogeneous electro-Fenton (HEF) treatment of organic micropollutants at mild pH. The synthesized MIL-88B(Fe)/Fe 3 S 4 hybrids possessed numerous and durable unsaturated iron sites, acting the S2− atoms as electron donors that enhanced the Fe(II) recycling. The sulfidated catalyst outperformed the MIL-88B(Fe), as evidenced by the 7-fold faster degradation of antibiotic trimethoprim by HEF and the fast destruction of micropollutants in urban wastewater. The hybrid catalyst was reused, obtaining >90% drug removal after four runs and, additionally, its inherent magnetism facilitated the post-treatment recovery. Electrochemical tests and DFT calculations provided mechanistic insights to explain the enhanced catalysis, suggesting that the accelerated Fe(III)/Fe(II) cycling and the enhanced mass transport and electron transfer accounted for the efficient trimethoprim degradation. [ABSTRACT FROM AUTHOR]

Graphene inducing graphitization of hard carbon can be realized via assemble of PF and GO with hydrogen bonding, and sequential inducing tendency during carbonization process. [Display omitted] • A hard carbon with less defects and lower specific surface area is synthesized. • The unique structure is realized via graphene induced graphitization of hard carbon. • The hard carbon exhibits ultrahigh initial coulombic efficiency (90.4%). • A Na-ion full cell with great stability and superior rate capability is demonstrated. Hard carbons exhibit great potential as anode materials for Sodium-ion batteries (SIBs). However, the large initial irreversible capacity is still a major obstacle in their practical application. It is widely known that lower surface area and fewer defects may increase the initial Coulombic efficiency (ICE) for carbon anode in SIBs. In this study, a graphene-induced graphitization strategy is proposed for synthesizing less defective hard carbon. This strategy is realized through the assembly of phenolic resin (PF) and graphene oxide (GO) taking advantage of their hydrogen bonding interaction. Thus, aromatic ring near graphene has a strong tendency to be arranged along the graphene layer during pyrolysis process, a significant transition from sp 3 to sp 2 hybridization carbon occurs, endowing hard carbon with fewer defects and lower surface area. The structural advantages of the hard carbon contribute to the superior ICE (90.4%), the highest ever reported, and excellent reversible specific capacity of 343 mA h g−1 at 30 mA g−1 even after 100 cycles. [ABSTRACT FROM AUTHOR]

We propose and realize a new nano lead-doped mesoporous carbon composite as the negative electrode additives, which realize the abundant nano-lead electrodeposition into carbon pores and the remarkable suppression of irreversible sulfation, to effectively prolong the cycle life of lead-carbon batteries. We show that through NaOH activation and followed air oxidation, porous carbon could obtain more mesopore volume and appropriate acidic groups, which are two critical parameters for effective nano-lead electrodeposition on the internal surface of them. We for the first time demonstrate that these mesopore system could be loaded much more deposits in them, and confine the size of lead deposits to be in nano scale by their local effect, ensuring a much more remarkable suppression of hydrogen evolution and better reversibility of Pb/PbSO 4 . In addition, we show that these nano-lead electrodeposits could stably contribute remarkable pseudocapacitance. All these merits contribute to the ultralong cyclability achieved by lead-carbon batteries, which will translate into promising inexpensive systems that could revolutionize the large-scale energy storage fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel heterogeneous lead iodide, exhibiting two (0 0 1) interplanar distances of 6.9 Å and 9.0 Å, was constructed. • The heterogeneous structure can regulate the crystallization process of PbI 2 and perovskite films. • The V OC and PCE were raised to 1.21 V and 24.24%. At present, the highest power conversion efficiency (PCE) of perovskite solar cells (PSCs) has exceeded 25%, which exhibits great potential for commercial applications. Obtaining pinhole-free, superior crystal, and high-quality perovskite films with fewer defects by adjusting the lead iodide (PbI 2) intermediate films in a two-step sequential deposition has become research arousing general interest. Herein, a heterogeneous lead iodide (HLI) structure with two (0 0 1) interplanar distances (9.0 Å and 6.9 Å), can optimize the crystallization process of perovskite to get better surface morphology and is constructed by intercalated choline chloride (a kind of vitamin B4, VB4). HLI simultaneously improves the carrier lifetime of perovskite film from 1.96 µs to 3.28 µs and reduces defect state density. Together with better morphology and lower defect state density, the open circuit voltage (V OC) and PCE based on (FAPbI 3) 0.97 (MAPbBr 3) 0.03 is significantly boosted. In addition, with double-sided modification, HLI produces an excellent PCE of 24.27% with a V OC of 1.21 V. We believe that the novel heterogeneous PbI 2 structure could be a generic method to improve the efficiency of PSCs. [ABSTRACT FROM AUTHOR]