High rate capability and cyclic stability of hierarchically porous Tin oxide (IV)–carbon nanofibers as anode in lithium ion batteries

Self-Supported Fibrous Sn/SnO2@C Nanocomposite as Superior Anode Material for Lithium-Ion Batteries

Low-cost and simple methods are constantly chased in order to produce less expensive lithium-ion batteries (LIBs) while possibly increasing the energy and power density as well as the volumetric capacity in order to boost a rapid decarbonization of the transport sector. Li alloys and tin-carbon composites are promising candidates as anode materials for LIBs both in terms of capacity and cycle life. In the present paper, electrospinning was employed in the preparation of Sn/SnO_x@C composites, where tin and tin oxides were homogeneously dispersed in a carbonaceous matrix of carbon nanofibers. The resulting self-standing and light electrode showed a greatly enhanced performance compared to a conventional electrode based on the same starting materials that are simply mixed to obtain a slurry then deposited on a Cu foil. Fast kinetics were achieved with more than 90% of the reaction that resulted being surface-controlled, and stable capacities of about 300 mAh/g over 500 cycles were obtained at a current density of 0.5 A/g.

Quasi-anisotropic benefits in electrospun nickel–cobalt–manganese oxide nano-octahedron as anode for lithium-ion batteries

A polyhedral Ni–Co–Mn–O nano-octahedron anode for lithium-ion batteries was synthesized, which demonstrated enhanced lithium storage properties as compared to the nanofiber counterpart.

Ultrahigh Selective Room-Temperature Ammonia Gas Sensor Based on Tin-Titanium Dioxide/reduced Graphene/Carbon Nanotube Nanocomposites by the Solvothermal Method

Resistive-based gas sensors have been considered as the most favorable gas sensors for detection of toxic gases and volatile organic compounds (VOCs) because of their simple structure, low cost, high sensitivity, ease of use, and high stability. Unfortunately, wide application of resistive-based gas sensors is limited by their low selectivity. In this article, we present the fabrication of ultrahigh selective NH₃ gas sensor based on tin-titanium dioxide/reduced graphene/carbon nanotube (Sn-TiO₂@rGO/CNT) nanocomposites. The Sn-TiO₂@rGO/CNT nanocomposites with different molar ratios of Sn/Ti (1:10, 3:10, and 5:10) were synthesized via the solvothermal method. Characterizations by scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy confirmed the decoration of Sn-TiO₂ nanoparticles on rGO/CNT nanocomposite surfaces. The Sn-TiO₂@rGO/CNT nanocomposite gas sensor exhibited high response and ultrahigh selectivity to NH₃ against toluene, dimethylformamide, acetone, ethanol, methanol, isopropanol, formaldehyde, hydrogen, carbon dioxide, acetylene, and VOCs in paint thinners at room temperature. The Sn-TiO₂@rGO/CNT nanocomposite gas sensor with molar ratio of Sn/Ti = 1:10 showed the highest response to NH₃ over other molar ratios of Sn/Ti as well as pure rGO/CNT and Sn-TiO₂ gas sensors. The ammonia-sensing mechanisms of the Sn-TiO₂@rGO/CNT gas sensor were proposed based on the formation of p-n heterojunctions of p-type rGO/CNT and n-type Sn-TiO₂ nanoparticles via a low-temperature oxidizing reaction process.

Tin Oxide Based Nanomaterials and Their Application as Anodes in Lithium-Ion Batteries and Beyond

Herein, recent progress in the field of tin oxide (SnO2 )-based nanosized and nanostructured materials as conversion and alloying/dealloying-type anodes in lithium-ion batteries and beyond (sodium- and potassium-ion batteries) is briefly discussed. The first section addresses the importance of the initial SnO2 micro- and nanostructure on the conversion and alloying/dealloying reaction upon lithiation and its impact on the microstructure and cyclability of the anodes. A further section is dedicated to recent advances in the fabrication of diverse 0D to 3D nanostructures to overcome stability issues induced by large volume changes during cycling. Additionally, the role of doping on conductivity and synergistic effects of redox-active and -inactive dopants on the reversible lithium-storage capacity and rate capability are discussed. Furthermore, the synthesis and electrochemical properties of nanostructured SnO2 /C composites are reviewed. The broad research spectrum of SnO2 anode materials is finally reflected in a brief overview of recent work published on Na- and K-ion batteries.

A Convenient Synthesis Route for Co3O4 Hollow Microspheres and Their Application as a High Performing Anode in Li-Ion Batteries

A new, rapid, and cost-effective method for synthesizing hollow microspheres (HMSs) of cobalt oxide (Co₃O₄) using the phloroglucinol-formaldehyde gel route is reported here. Further, the synthesized hollow Co₃O₄ microspheres were investigated as an anode material for Li-ion batteries. The Co₃O₄ hollow spheres exhibited excellent electrochemical performance and cycling stability, for example, a capacity of 915 mA h g^-1 was obtained at 1 C rate over 350 cycles. The material also exhibited good performance at high rates, viz., capacities of 500, 350, and 250 mA h g^-1 at 10 C, 25 C, and 50 C, respectively, with good capacity retention over 500 cycles. The excellent electrochemical performance of Co₃O₄ can be ascribed to the porous nanoarchitecture that provides a short diffusion length for Li⁺ ions and high electrolyte percolation in the porous structure. Additionally, the thin porous wall of the nanocages provides an effective way to overcome the issues associated with the volume change occurring during Li charge/discharge. The conversion of Co₃O₄ into Co upon discharge was also probed by measuring the magnetic properties.