Shiyong Zuo

2D hybrid anode based on SnS nanosheet bonded with graphene to enhance electrochemical performance for lithium-ion batteries

A hybrid anode based on SnS nanosheets bonded with reduced graphene oxide (SnS NS/RGO) and synthesized with graphene oxide is formed through a facile solvothermal method. It is found that the 2D SnS nanosheets with few layers are well dispersed on the crumpled reduced graphene oxide surface. Electrochemical tests indicate that the SnS NS/RGO hybrid exhibits a very high reversible capacity (791 mA h g−1) with excellent cycle stability and significantly enhanced rate capability. The factors contributing to the enhanced electrochemical performance of the hybrid anode can be ascribed to the chemically bonded interface between SnS NS and RGO, creating effective charge transportation with electron coupling in the novel two-dimensional composite nanostructure. This work provides insights into the structural design of SnS-based hybrid electrode materials, which will be important for the future development of high performance electrode materials.

3D-hierarchical SnS nanostructures: controlled synthesis, formation mechanism and lithium-ion storage performance

A series of SnS nanocrystals with tunable morphology and sheet thickness have been prepared through a solvothermal method and by introducing selective additives to the solution. Such SnS nanocrystals exhibit hierarchical hollow structures of SnS nanoflowers assembled from nanosheets. The formation of the SnS hollow micro-flowers is based on an inside–out Ostwald ripening mechanism. By adjusting the additive and concentration, we can grow SnS nanosheets of about 14 nm thick, at which thickness the band gap of SnS can be expected to increase so as to give an opportunity to explore the structure-related novel properties and superior device performance. As one application for these SnS nanostructure, properties vs. morphology for lithium storage were investigated, and it is shown that the SnS porous spheres built with scale-like ultrathin nanosheets exhibited the best performance.

3D flower-like hierarchitectures constructed by SnS/SnS 2 heterostructure nanosheets for high-performance anode material in lithium-ion batteries

Sn chalcogenides, including SnS, Sn2S3, and SnS2, have been extensively studied as anode materials for lithium batteries. In order to obtain one kind of high capacity, long cycle life lithium batteries anode materials, three-dimensional (3D) flowerlike hierarchitectures constructed by SnS/SnS2 heterostructure nanosheets with thickness of ∼20nm have been synthesized via a simple one-pot solvothermal method. The obtained samples exhibit excellent electrochemical performance as anode for Li-ion batteries (LIBs), which deliver a first discharge capacity of 1277 mAhg-1 and remain a reversible capacity up to 500 mAhg-1 after 50 cycles at a current of 100 mAhg-1.

Preparation of mono-dispersed, high energy release, core/shell structure Al nanopowders and their application in HTPB propellant as combustion enhancers

Mono-dispersed, spherical and core/shell structure aluminum nanopowders (ANPs) were produced massively by high energy ion beam evaporation (HEIBE). And the number weighted average particle size of the ANPs is 98.9 nm, with an alumina shell (3–5 nm). Benefiting from the passivation treatment, the friction, impact and electrostatic spark sensitivity of the ANPs are almost equivalent to those of aluminum micro powders. The result of TG-DSC indicates the active aluminum content of ANPs is 87.14%, the enthalpy release value is 20.37 kJ/g, the specific heat release S1/Δm1* (392–611 °C) which determined the ability of energy release is 19.95 kJ/g. And the value of S1/Δm1* is the highest compared with ANPs produced by other physical methods. Besides, the ANPs perfectly compatible with hydroxyl-terminated polybutadiene (HTPB), 3 wt. % of ANPs were used in HTPB propellant replaced micron aluminum powders, and improved the burning rate in the 3–12 MPa pressure range and reduced the pressure exponential by more than 31% in the 3–16 MPa pressure range. The production technology of ANPs with excellent properties will greatly promote the application of ANPs in the field of energetic materials such as propellant, explosive and pyrotechnics.

High rate performance SnO2 based three-dimensional graphene composite electrode for lithium-ion battery applications

In order to improve the rate performance and cycling stability at high current densities of lithium-ion batteries (LIBs), a sample composite of SnO2 and three-dimensional graphene (SnO2/3DG) was fabricated using a hydrothermal method, with polystyrene balls (PS) as templates. The reversible capacity is 720.8 mA h g−1 at a current density of 100 mA g−1, after 100 cycles. The rate performance is also excellent, with a reversible capacity of about 800 mA h g−1 at 1000 mA g−1. The excellent electrochemical performance is attributed to its 3D structure, which possesses a large specific surface area and abundant reaction active positions, leading to fast kinetics and short pathways for both Li-ions and electrons.

Methods to form atomically thin carbon coatings on SnS and SnO2 nanostructures

We report a citric acid-assisted solvothermal method to construct C@SnS@C sandwich nanosheets, which assemble into 3D porous microspheres. Citric acid plays a key role in both controlling the growth of the thin (5 nm) SnS nanosheets by absorption on the (100) SnS surface, and in the formation of an amorphous atomically thin carbon (ATC) layer (0.8 nm) on the surface of SnS nanocrystals through carbonization. The C@SnS@C sandwich nanosheets are used as precursors to form porous microsphere SnO2@ATC composites, with the SnO2 nanoparticles (10–20 nm) grown on the extended carbon framework. We demonstrate how the synergetic effect of the high theoretical lithium storage capacity of SnO2 and electrical conductivity of the atomically thin carbon framework renders this composite a promising anode material for lithium ion batteries with enhanced capacity and superior cycling performance.

Large-size and high performance visible-light photodetectors based on two-dimensional hybrid materials SnS/RGO

We report a facile solvothermal method to synthesize two-dimensional hybrid materials consisting of layered SnS nanosheets and reduced graphene oxide (SnS/RGO). Large-size photodetectors with a channel length/width = 2 mm/7 mm are fabricated on Si/SiO2 substrates, showing an excellent photoresponsivity of 0.18 A W−1 under visible-light illumination with a detectivity of 4.18 × 1010 Jones, as well as fast rise and decay times (τrise = τdecay = 0.4 s). SnS/RGO hybrids are therefore promising candidates for potential applications in optoelectronics and low cost, high performance, and reliable photodetectors.