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Shuttle effect and slow redox reactions in Li-S battery limit its commercial application. Herein, TiN nanotubes with N-doped carbon coating (TiN/N-C NT) were obtained via MoO 3 nanorod template-assistant hydrothermal method and followed by polydopamine coating and carbonization/nitriding. When used as sulfur host, the tubular structure buffers the volume change in lithiation process and shortens Li+ transfer route. Consequently, the TiN/N-C NT cathode exhibits a high capacity of 1010.3 mAh g−1 over 100 cycles at 0.1 A g−1. It provides a low capacity decay rate of 0.057 % per cycle over 500 cycles at a high current density of 1.0 A g−1. This study provides a promising method for preparing high-performance Li-S battery. • Special TiN nanotubes coated with N-doped carbon layer were developed. • It involves template-assistant hydrothermal method, PDA coating and carbonization/nitriding. • TiN/N-C nanotubes exhibit high stable capacity and superior rate performance. • High performance is due to thier hollow structure and strong LiPSs chemisorption. [ABSTRACT FROM AUTHOR]

Abstract Hierarchical MoS 2 microplates, consisting of numerous crosslinked nanosheets, are successfully synthesized using a self-sacrificial template method. MoO 3 microplates (synthesized using a solution method) are used as the self-sacrificial template in the solvent thermal sulfidation process, resulting in the formation of MoS 2 microplates. The resulting hierarchical structure possesses numerous active sites and a large surface area. As an anode material for LIBs, the hierarchical MoS 2 microplates, both before and after the thermal treatment, demonstrate reversible and high capacity, and good rate capability. In addition, the energy storage performance of the MoS 2 microplates is found to be significantly improved after thermal treatment. The annealed MoS 2 microplates deliver a high specific capacity of 1220.8 mAh g−1 at a current density of 0.1 A g−1 and a high capacity retention of 84.8% (of the initial capacity) over 130 cycles. The high capacity and good rate capability suggest that the as-prepared hierarchical MoS 2 microplates are a promising anode material for LIBs. Highlights • Hierarchical MoS 2 microplates were developed. • Quality of hierarchical MoS 2 microplates was improved after thermal treatment. • Hierarchical MoS 2 microplates exhibit high stable capacity and rate performance. • High performance is ascribed to the hierarchical nanostructure and carbon. [ABSTRACT FROM AUTHOR]

The design engineering of a hierarchical bimetallic composite anode is a critical part of the high-performance lithium-ion battery. This study developed a one-step sulfurization route to prepare hierarchical Cu 3 SnS 4 −Cu 2 SnS 3 hollow nanocapsules (CTS HNCs) using CuSn(OH) 6 nanorods as sacrificial templates. The final Cu 3 SnS 4 −Cu 2 SnS 3 /N-doped carbon hollow nanocapsules (CTS/N-C HNCs) were obtained by coating the hollow nanocapsules with polydopamine, followed by calcination. As an anode material, the CTS/N-C HNC electrode demonstrated a high capacity (827.8 mAh g−1 at 0.2 A g−1 over 150 cycles), superior long-cycling performance (409.1 mAh g−1 at 1.0 A g−1 over 500 cycles) and outstanding rate performance (average discharge capacity of 374 mAh g−1 at 5.0 A g−1). Hence, the CTS/N-C HNCs composites with a hollow structure, outer assembled nanosheets, and N-doped carbon layer are conducive to controlled volume changes during the intercalation/deintercalation process and accelerate the electron/Li+ transport. Briefly, this research provides a facile strategy for constructing CTS-based hierarchical composites, contributing to the further development of LIBs. • A special hierarchical hollow bimetallic sulfides Cu 3 SnS 4 −Cu 2 SnS 3 /N-C was developed. • It involves a sacrificial template sulfurization route and a carbon coating process. • Cu 3 SnS 4 −Cu 2 SnS 3 /N-C nanocapsules exhibit high stable capacity and rate performance. • High performance is due to bimetallic effect, hollow structure and N-carbon coating. [ABSTRACT FROM AUTHOR]

Porous flower-like tin oxide (SnO 2 ) structures were obtained using a hydrothermal method combined with a subsequent calcination and acid-washing process. The morphologies and crystal structures of the products were characterized by field emission scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller N 2 adsorption-desorption analyses. The process of inducing porosity begins with a flower-like nickel tin sulfur precursor. Thermal decomposition of this flower-like nickel tin sulfur precursor leads to an intimate mixture of porous flower-like NiO/SnO 2 hybrids. Porous SnO 2 flowers were obtained after removing the cubic phase NiO by an acid-washing process. Furthermore, the gas sensing properties of the as-prepared porous SnO 2 flowers to VOCs, such as ethanol, formaldehyde, benzene, toluene, and acetone, were investigated. The porous SnO 2 flowers showed a good response and reversibility to some organic vapors, such as ethanol and formaldehyde. The sensing responses to 100 ppm ethanol and formaldehyde were 42.4 and 24.8, respectively. The sensors also exhibited a good response to benzene, toluene, methanol, and 2-propanol. The relationship between the gas-sensing properties and the microstructure of the as-prepared flower-like SnO 2 structures was also examined. [ABSTRACT FROM AUTHOR]

Au nanoparticle-modified porous TiO 2 (Au@TiO 2) nanospheres were prepared using a simple hydrothermal route followed by liquid reduction. Au NPs with a diameter of ~12 nm were well anchored on the surfaces of porous TiO 2 nanospheres by epitaxial growth as their crystal planes had similar spacings. The sensing behavior of Au@TiO 2 nanospheres was investigated using various organic vapors. Au@TiO 2 nanospheres show higher responses towards 100 ppm formaldehyde, acetone, ethanol, and isopropanol with respective response values of 45.2, 55, 29, and 50 at a working temperature of 220 °C. The response/recovery times of the Au@TiO 2 sensor for 100 ppm acetone vapor were 12 s and 13 s, respectively. These excellent sensing results indicate Au nanoparticle-modified porous TiO 2 nanospheres are promising sensing material for the accurate detection of toxic volatile vapors. [Display omitted] • Au nanoparticle-modified porous TiO 2 nanospheres were developed. • Au NPs were well anchored on porous TiO 2 nanospheres by epitaxial growth. • Porous Au@TiO 2 nanospheres exhibit superior sensing property for organic vapors. • High performance is due to the porous nanostructure and catalytic activity of Au NPs. [ABSTRACT FROM AUTHOR]

Gallium oxide as an anode material for lithium-ion batteries has attracted attention because of its high specific capacity. As reported previously, N-doped carbon coated Ga 2 O 3 nanopapers exhibited a high discharge capacity of 477 mAh g−1 after 200 cycles at 0.2 A g−1. But the rate performance and cycling stability of the Ga 2 O 3 –based anode still need to be improved. Herein, Ga 2 O 3 nanotubes coated with N-doped carbon layers (Ga 2 O 3 /N-C NTs) were prepared using MoO 3 nanorods as sacrificial templates followed by a polydopamine coating and heat treatment process. The resulting tubular structure provided cavities for volume changes of the Ga 2 O 3 in the cycling process and shortened the migration path of Li ions and electrons. The N-doped carbon coated Ga 2 O 3 NTs delivered a capacity of 1185.3 mAh g−1 after 100 cycles at 0.1 A g−1 and outstanding stability of 535.5 mAh g−1 after 500 cycles at 1.0 A g−1. This study supplies a novel method for preparing Ga 2 O 3 anode materials to promote the performance of lithium-ion battery. • A special Ga 2 O 3 nanotubes coated with N-doped carbon layers was developed. • It involves a sacrificial template hydrothermal method and a carbon coating process. • Ga 2 O 3 /N-C nanotubes exhibit high stable capacity and superior rate performance. • High electrochemical performance is due to hollow structure and N-carbon coating. [ABSTRACT FROM AUTHOR]

Semiconductor metal oxide nanostructures with large specific surface areas and high porosity will enhance their gas-sensing performance. Here, cross-linked porous tin dioxide nanosheets were obtained using three-dimensional reduced graphene oxide as a template followed by an annealing process. The as-synthesized porous SnO 2 nanosheets were composed of nanocrystals with a mean diameter of ca. 7.6 nm. The products were characterized using a range of techniques. The sensing property of the cross-linked porous SnO 2 nanosheets for toxic organic vapors, such as ethanol, acetone, isopropanol, benzene, methylbenzene, methanol, and formaldehyde, were studied. The sensor showed a high response of 37.9 for 100 ppm acetone, making it a promising candidate as a practical detector of volatile organic compounds. [Display omitted] • A special cross-linked porous tin dioxide nanosheets were developed. • It involves a template solvothermal method and a subsequent annealing process. • The cross-linked porous SnO 2 nanosheets exhibit high sensing performance for VOCs. • High performance is due to cross-linked structure with small size nanocrystals. [ABSTRACT FROM AUTHOR]

• A special porous CoMn 2 O 4 nanocubes was developed. • It involves a template precipitation method and a subsequent annealing process. • The CoMn 2 O 4 /S@PPy nanocubes exhibit high stable capacity and rate performance. • High performance is due to bimetallic effect, porous structure and PPy coating. [Display omitted] Lithium–sulfur (Li–S) batteries suffer from the poor conductivity originated from sulfur and shuttle effect arisen from the polysulfides dissolution. Herein, cobalt manganate (CoMn 2 O 4) porous nanocubes coated with polypyrrole (PPy) as sulfur carrier are prepared using MnCO 3 nanocube template through a precipitation method and a subsequent annealing process. The unique approach can obtain porous CoMn 2 O 4 nanocubes with uniform morphology and abundant exposed active sites. The plentiful mesopores among the porous nanocubes are beneficial to accommodation of sulfur. In addition, the porous CoMn 2 O 4 nanocubes can trap polysulfides in the cycling process owing to the chemical bonds between CoMn 2 O 4 and polysulfides. Moreover, PPy coating severed as conductive layer not only enhances electrical conductivity of the cathode, but also confines polysulfides via the formation of N–Li–S bonds during cycling process. Therefore, the porous CoMn 2 O 4 /S@PPy nanocubes with 66.9% sulfur mass content delivered a capacity of 533 mAh g−1 over 500 cycles at 1 A g−1 with a capacity decay rate of 0.064% each cycle, and a Coulombic efficiency of 98%, suggesting the enhanced cycling performance of cathode. The facile template precipitation method combined with an annealing process contribute a new approach to synthesize unique porous CoMn 2 O 4 structure as sulfur carrier for Li–S batteries [ABSTRACT FROM AUTHOR]

• A special hollow cubic SnO 2 /ZnS@C composite was developed. • It involves a sacrificial template method and a subsequent carbon coating process. • The SnO 2 /ZnS@C composite exhibit high stable capacity and rate performance. • High performance is due to bimetallic effect, hollow structure and carbon coating. [Display omitted] Nanostructured SnO 2 and ZnS have been proved to application prospects in lithium-ion battery. However, some severe challenges, such as rapid capacity decay due to volume expansion during the charge/discharge process and poor conductivity, limit their applications. Herein, a hollow cubic SnO 2 /ZnS@C composite was obtained using ZnSn(OH) 6 cubes as precursor via a hydrothermal reaction and a subsequent carbon coating process. Served as anode material, the SnO 2 /ZnS@C nanocubes exhibit an initial capacity of 1312.8 mAh g−1 at 0.1 A g−1, the coulombic efficiency reaches 73.1%, and it remains 753.5 mA g−1 over 200 cycles. Moreover, rate capacities of SnO 2 /ZnS@C composite reach up to 818, 757 and 693 mAh g−1 at 0.2, 0.5 and 1.0 A g−1, respectively. The SnO 2 /ZnS@C nanocubes exhibit the superior performance due to the synergistic effect of Sn and Zn, the hollow structure and the carbon coating. [ABSTRACT FROM AUTHOR]