Chitosan modulated engineer tin dioxide nanoparticles well dispersed by reduced graphene oxide for high and stable lithium-ion storage

Interfacial engineering in SnO2-embedded graphene anode materials for high performance lithium-ion batteries

Tin dioxide is regarded as an alternative anode material rather than graphite due to its high theoretical specific capacity. Modification with carbon is a typical strategy to mitigate the volume expansion effect of SnO2 during the charge process. Strengthening the interface bonding is crucial for improving the electrochemical performance of SnO2/C composites. Here, SnO2-embedded reduced graphene oxide (rGO) composite with a low graphene content of approximately 5 wt.% was in situ synthesized via a cetyltrimethylammonium bromide (CTAB)-assisted hydrothermal method. The structural integrity of the SnO2/rGO composite is significantly improved by optimizing the Sn-O-C electronic structure with CTAB, resulting a reversible capacity of 598 mAh g-1 after 200 cycles at a current density of 1 A g-1. CTAB-assisted synthesis enhances the rate performance and cyclic stability of tin dioxide/graphene composites, and boosts their application as the anode materials for the next-generation lithium-ion batteries.

Research progress on polybenzoxazine aerogels: Preparation, properties, composites and hybrids fabrication, applications

The unremitting pursuit of high-performance and multifunctional materials has consistently propelled modern industries forward, stimulating research and motivating progress in related fields. In such materials, polybenzoxazine (PBz) aerogel, which combines the virtues of PBz and aerogel, has attracted salient attention recently, emerging as a novel research focus in the realm of advanced materials. In this review, the preparation scheme, microscopic morphology, and fundamental characteristics of PBz aerogels are comprehensively summarized and discussed in anticipation of providing a clear understanding of the correlation between preparation process, structure, and properties. The effective strategies for enhancing the performance of PBz aerogels including composite fabrication and hybridization are highlighted. Moreover, the applications of PBz-based aerogels in various domains such as adsorption (including wastewater treatment, CO2 capture, and microwave adsorption), thermal insulation, energy storage as well as sensors are covered in detail. Furthermore, several obstacles and potential directions for subsequent research are delineated with a view to surmounting the prevailing constraints and achieving a realization of the shift from experimental exploration to practical applications.

Carbon-Coated Tin-Titanate derived SnO2/TiO2 nanowires as High-Performance anode for Lithium-Ion batteries

Tin dioxide (SnO2) is a promising alternative material to graphite anode, but the large volume change induced electrode pulverization issue has limited its application in lithium-ion batteries (LIBs). In contrast, titanium dioxide (TiO2) anode shows high structure stability upon lithium insertion/extraction, but with low specific capacity. To overcome their inherent disadvantages, combination of SnO2 with TiO2 and highly conductive carbon material is an effective way. Herein, we report a facile fabrication method of carbon-coated SnO2/TiO2 nanowires (SnO2/TiO2@C) using tin titanate nanowires as precursor, which are prepared by reacting SnCl2·2H2O with layered sodium titanate (Na2Ti3O7) nanowires in the aqueous solution though the ion exchange between Sn2+ and Na+. After annealing under argon atmosphere, the hydrothermally carbon-coated tin-titanate nanowires decompose, forming a unique hybrid structure, where ultrafine SnO2 nanoparticles are uniformly embedded within the TiO2 substrate with carbon coating. Consequently, the SnO2/TiO2@C nanowires demonstrate excellent lithium storage capacity with high pseudocapacitance contribution, excellent reversible capacity, and long-term cycling stability (673.7/510.5 mAh/g at 0.5/1.0 A/g after 250/800 cycles), owing to the unique hybrid structure, as the well-dispersion of ultra-small SnO2 within TiO2 nanowire substrate with simultaneous carbon coating efficiently suppresses the volume changes of SnO2, provides abundant reactive sites for lithium storage, and enhances the electrical conductivity with shortened ion transport distance.

Engineering a hierarchical reduced graphene oxide and lignosulfonate derived carbon framework supported tin dioxide nanocomposite for lithium-ion storage

Tin dioxide (SnO2) 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 SnO2 and further immobilizing SnO2 with supportive carbon frameworks via eco-friendly and cost-effective approaches are challenging tasks. In this work, biomass sodium lignosulfonate (LS-Na), stannous chloride (SnCl2) and a small amount of few-layered graphene oxide (GO) are employed as raw materials to engineer a hierarchical carbon framework supported SnO2 nanocomposite. The spontaneous chelation reaction between LS-Na and SnCl2 under mild hydrothermal condition generates the corresponding SnCl2@LS sample with a uniform distribution of Sn2+ in the LS domains, and the SnCl2@LS sample is further dispersed by GO sheets via a redox coprecipitation reaction. After a thermal treatment, the SnCl2@LS@GO sample is converted to the final SnO2/LSC/RGO sample with an improved microstructure. The SnO2/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.