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The chelation reaction between LS-Na and SnCl 2 under mild hydrothermal condition generates the SnCl 2 @LS sample with a uniform distribution of Sn2+ in the LS domains, which can be further dispersed by GO sheets via a redox coprecipitation reaction. After thermal treatment, the SnCl 2 @LS@GO sample can be converted to the SnO 2 /LSC/RGO composite with improved micro-structure. [Display omitted] Tin dioxide (SnO 2) is widely recognized as a high-performance anode material for lithium-ion batteries. To simultaneously achieve satisfactory electrochemical performances and lower manufacturing costs, engineering nano-sized SnO 2 and further immobilizing SnO 2 with supportive carbon frameworks via eco-friendly and cost-effective approaches are challenging tasks. In this work, biomass sodium lignosulfonate (LS-Na), stannous chloride (SnCl 2) and a small amount of few-layered graphene oxide (GO) are employed as raw materials to engineer a hierarchical carbon framework supported SnO 2 nanocomposite. The spontaneous chelation reaction between LS-Na and SnCl 2 under mild hydrothermal condition generates the corresponding SnCl 2 @LS sample with a uniform distribution of Sn2+ in the LS domains, and the SnCl 2 @LS sample is further dispersed by GO sheets via a redox coprecipitation reaction. After a thermal treatment, the SnCl 2 @LS@GO sample is converted to the final SnO 2 /LSC/RGO sample with an improved microstructure. The SnO 2 /LSC/RGO nanocomposite exhibits excellent lithium-ion storage performances with a high specific capacity of 938.3 mAh/g after 600 cycles at 1000 mA g−1 in half-cells and 517.1 mAh/g after 50 cycles at 200 mA g−1 in full-cells. This work provides a potential strategy of engineering biomass derived high-performance electrode materials for rechargeable batteries. [ABSTRACT FROM AUTHOR]

The redox coprecipitation reaction between the Fe foil, H 3 BTC molecules and GO sheets in mild hydrothermal condition leads to the in situ formation of Fe-BTC MOFs directly on the RGO sheets. The RGO sheets effectively inhibit the severe aggregation of small sized Fe-BTC domains, and the well distributed Fe-BTC domains could prevent the spontaneous restacking of the RGO sheets. [Display omitted] Fe based metal organic framework (MOF) materials are being extensively investigated as a precursor sample for engineering carbon supported iron containing nanoparticles composites. Rational design and engineering Fe-containing MOFs with optimized structures using economic and eco-friendly methods is a challenging task. In this work, 1,3,5-benzenetricarboxylic acid (C 9 H 6 O 6 , trimesic acid, H 3 BTC) and metal Fe are employed to synthesize a MOF sample Fe-BTC in a mild hydrothermal condition. Moreover, with the addition of a small quantity of graphene oxide (GO) as dispersant, a redox coprecipitation reaction has taken place where small Fe-BTC domains well dispersed by reduced graphene oxide (RGO). The Fe-BTC/RGO intermediate sample is finally converted to the hierarchical Fe 3 O 4 @C/RGO composite, which delivers an ultrahigh specific capacity of 1262.61 mAh·g−1 at 200 mA·g−1 after 150 cycles and a superior reversible capacity of 910.65 mAh·g−1 at 1000 mA·g−1 after 300 cycles in half cells. The full cell performance for the Fe 3 O 4 @C/RGO composite have been studied. It is also revealed that the improved structural stability, high pseudocapacitive contribution and enhanced lithium-ion and electron transportation conditions jointly guarantee the outstanding lithium-ion storage performances for the Fe 3 O 4 @C/RGO composite over long-time cycling. The synthesized samples have good potential for wider application. [ABSTRACT FROM AUTHOR]

A facile preparation protocol for a porous carbon skeleton supported lithium iron phosphate nanocomposite material (LFP/C) is derived from a ferric gallate (Fe-GA) metal–organic framework (MOF) precursor. [Display omitted] Lithium iron phosphate (LiFePO 4 , LFP) has become one of the most widely used cathode materials for lithium-ion batteries. The inferior lithium-ion diffusion rate of LFP crystals always incurs poor rate capability and unsatisfactory low-temperature performances. To meet with the requirements from the ever-growing market, it is of great significance to synthesize carbon supported LFP nanocomposite (LFP/C) cathode materials using cost effective and environmentally friendly methods. In this work, an LFP/C cathode material is straightforwardly prepared from a metal–organic framework (MOF) precursor ferric gallate (Fe-GA) using its self-template effect. The Fe-GA precursor is firstly fabricated from the redox coprecipitation reaction between Fe foils and gallic acid (GA) molecules in mild aqueous phase. Then the Fe-GA is directly converted to the LFP/C sample after a following solid-state reaction. In half-cells, the LFP/C composite exhibits a reversible capacity of 109.7 mAh·g−1 after 500 cycles under the current rate of 100 mA·g−1 at 25 °C as well as good rate capabilities. In the LFP/C//graphite full-cells, the LFP/C composite can deliver a reversible capacity of 71.4 mAh·g−1 after 50 cycles in the same condition as the half-cells. The electrochemical performances of the LFP/C cathode in half-cells at lower temperature of −10 °C are also examined. Particularly, the evolution of samples has been explored and the lithium-ion storage mechanism of the LFP/C cathode has been unveiled. The sample synthesis protocol is straightforward, eco-friendly and atomic efficient, which can be considered to have good potential for scaling-up. [ABSTRACT FROM AUTHOR]

The rationally designed reaction between the GO sheets, Sn2+ ions and GA molecules in mild hydrothermal condition contributes to the formation of an intermediate SnO 2 @GA@RGO sample with a MOF on graphene configuration, which is converted to the final SnO 2 /C/RGO composite with optimized microstructures after thermal treatment. [Display omitted] Tin dioxide (SnO 2) is being investigated as a promising anode material for both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Effectively dispersing small sized SnO 2 crystals in well-designed carbonaceous matrices using eco-friendly materials and simplified methods is an urgent task. Herein, gallic acid (GA) molecules, abundant in plant kingdom, are firstly selected to react with few-layered graphene oxide (GO) in mild hydrothermal condition, and the GA modulated reduced graphene oxide (GA@RGO) supporting skeleton can be obtained. Then Sn-GA metal–organic framework (MOF) domains can be directly engineered on the surface of the GA@RGO sheets with controlled size and improved dispersion. Finally, the well-designed Sn-GA@RGO precursor is converted to the SnO 2 /C/RGO nanocomposite with significantly optimized microstructure. The SnO 2 /C/RGO sample delivers an excellent specific capacity of 823.6 mAh·g−1 after 700 cycles at 1000 mA·g−1 in half-cells and 741.3 mAh·g−1 after 50 cycles at 200 mA·g−1 in full-cells for LIBs, a specific capacity of 370.3 mAh·g−1 after 600 cycles at 200 mA·g−1 in half-cells for SIBs. The sample preparation strategy is rationally established by comprehensively understanding the interactions between GO sheets, Sn2+ ions and GA molecules, and the engineered SnO 2 /C/RGO nanocomposite has good prospects in wider fields. [ABSTRACT FROM AUTHOR]

A well-designed strategy is demonstrated to consecutively engineer a homogeneously dispersed cobalt monoxide nanoparticle on reduced graphene oxide as a composite anode (CoO@RGO) and a nanosized lithium cobalt oxide (LiCoO 2 , LCO) cathode material, starting from metallic Co foils and few-layered graphene oxide (GO) aqueous suspension. [Display omitted] Downsizing the electrochemically active materials in both cathodic and anodic electrodes commonly brings about enhanced lithium-ion storage performances. It is particularly meaningful to explore simplified and effective strategies for exploiting nanosized electrode materials in the advanced lithium-ion batteries. In this work, the spontaneous reaction between few-layered graphene oxide (GO) and metallic cobalt (Co) foils in mild hydrothermal condition is for the first time employed to synthesize a reduced graphene oxide (RGO) supported nanosized cobalt monoxide (CoO) anode material (CoO@RGO). Furthermore, the CoO@RGO sample is converted to nanosized lithium cobalt oxide cathode material (LiCoO 2 , LCO) by taking the advantages of the self-templated effect. As a result, both the CoO@RGO anode and the LCO cathode exhibit inspiring lithium-ion storage properties. In half-cells, the CoO@RGO sample maintains a reversible capacity of 740.6 mAh·g−1 after 300 cycles at the current density of 1000 mA·g−1 while the LCO sample delivers a reversible capacity of 109.1 mAh·g−1 after 100 cycles at the current density of 100 mA·g−1. In the CoO@RGO//LCO full-cells, the CoO@RGO sample delivers a reversible capacity of 553.9 mAh·g−1 after 50 cycles at the current density of 200 mA·g−1. The reasons for superior electrochemical behaviors of the samples have been revealed, and the strategy in this work can be considered to be straightforward and effective for engineering both anode and cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Naturally available amylose (AM) serves as both reducing agent for few-layered graphene oxide (GO) in the first mild redox coprecipitation system and precursor for small-sized pyrolytic amylose-derived carbon (AMC) in the following thermal treatment. Compared with the Fe 3 O 4 @RGO sample, the crystal size and excessive exposure of Fe 3 O 4 nanoparticles, the over restacking of reduced graphene oxide (GO) sheets in Fe 3 O 4 @AMC/RGO composites are effectively controlled. [Display omitted] A straightforward and eco-friendly method is demonstrated to engineer magnetite (Fe 3 O 4) nanoparticles well dispersed by an amorphous amylose-derived carbon (AMC) and reduced graphene oxide (RGO) framework. Naturally available amylose (AM) serves as both reducing agent for few-layered graphene oxide (GO) in the first mild redox coprecipitation system and precursor for small-sized pyrolytic AMC in the following thermal treatment. In particular, the presence of the AM molecules effectively limits the crystal growth kinetics for the akaganeite (FeOOH) in the intermediate FeOOH@AM/RGO sample, which contributes to the transformation to Fe 3 O 4 nanoparticles with significantly controlled size in the final Fe 3 O 4 @AMC/RGO composite. As a result, both Fe 3 O 4 nanoparticles and AMC domains are adjacently anchored on the larger sized RGO sheets, and a unique hierarchical structure has been engineered in the Fe 3 O 4 @AMC/RGO sample. Compared with the controlled Fe 3 O 4 @RGO sample, the Fe 3 O 4 @AMC/RGO composite exhibits remarkably enhanced initial coulombic efficiency, superior cycling stability and rate performance for lithium-ion storage. The mechanisms of the interaction between GO sheets and AM molecules as well as the inspiring electrochemical behaviors of the Fe 3 O 4 @AMC/RGO electrode have been revealed. The Fe 3 O 4 @AMC/RGO sample possesses good potential for scaling-up and finding applications in wider fields. [ABSTRACT FROM AUTHOR]

Naturally available amylose (AM) serves as both reducing agent for few-layered graphene oxide (GO) in the first mild redox coprecipitation system and precursor for small-sized pyrolytic amylose-derived carbon (AMC) in the following thermal treatment. Compared with the Fe 3 O 4 @RGO sample, the crystal size and excessive exposure of Fe 3 O 4 nanoparticles, the over restacking of reduced graphene oxide (GO) sheets in Fe 3 O 4 @AMC/RGO composites are effectively controlled. [Display omitted] A straightforward and eco-friendly method is demonstrated to engineer magnetite (Fe 3 O 4) nanoparticles well dispersed by an amorphous amylose-derived carbon (AMC) and reduced graphene oxide (RGO) framework. Naturally available amylose (AM) serves as both reducing agent for few-layered graphene oxide (GO) in the first mild redox coprecipitation system and precursor for small-sized pyrolytic AMC in the following thermal treatment. In particular, the presence of the AM molecules effectively limits the crystal growth kinetics for the akaganeite (FeOOH) in the intermediate FeOOH@AM/RGO sample, which contributes to the transformation to Fe 3 O 4 nanoparticles with significantly controlled size in the final Fe 3 O 4 @AMC/RGO composite. As a result, both Fe 3 O 4 nanoparticles and AMC domains are adjacently anchored on the larger sized RGO sheets, and a unique hierarchical structure has been engineered in the Fe 3 O 4 @AMC/RGO sample. Compared with the controlled Fe 3 O 4 @RGO sample, the Fe 3 O 4 @AMC/RGO composite exhibits remarkably enhanced initial coulombic efficiency, superior cycling stability and rate performance for lithium-ion storage. The mechanisms of the interaction between GO sheets and AM molecules as well as the inspiring electrochemical behaviors of the Fe 3 O 4 @AMC/RGO electrode have been revealed. The Fe 3 O 4 @AMC/RGO sample possesses good potential for scaling-up and finding applications in wider fields. [ABSTRACT FROM AUTHOR]