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High-performance electrode materials are developed for flexible Li-ion batteries (FLIBs) and multifunctional electronic devices. In order to solve the problem of particle aggregation and large interfacial resistance in graphene/tin oxide (SnO2) flexible electrode, ultrathin SnO2 nanorods (NR) are used to fabricate freestanding graphene/SnO2-NR (GNS/SnO2-NR) paper electrode. Owing to the superior lithium storage behavior, the short diffusion length of Li+, and uniform dispersion of SnO2-NR, the GNS/SnO2-NR exhibits high reversible capacity (940 mAh g−1), excellent rate capability (625 mAh g−1 at 2000 mA g−1), and superior cyclic stability. Moreover, the FLIBs assembled with GNS/SnO2-NR paper electrodes can show high specific capacity and excellent cycle stability even in the state of long-term deformation. The structural design tactics point out a promising direction for the realization of mechanically compliant, ultra-stable FLIBs for the next-generation power hungry flexible/wearable electronic devices. [ABSTRACT FROM AUTHOR]

Preparing a heterojunction structure in different metal oxides is an efficacious method to improve the gas-sensing properties. In this article, a novelty SnO 2 nanorod/spindle-like Fe 2 O 3 heterostructure was successfully fabricated through a simple two-step hydrothermal route. The morphological characterization revealed that the spindle-shaped Fe 2 O 3 with length and diameter of 400 and 100 nm were firstly fabricated by a hydrothermal process, and then a large number of SnO 2 nanorods (lengths of 30 nm and diameterd of 8 nm) covered the spindle-shaped Fe 2 O 3 uniformly. In order to facilitate better practical applications, the gas sensing performance of sensors based on SnO 2 /Fe 2 O 3 nanostructures and pure Fe 2 O 3 nanospindles on volatile organic compounds were systematically studied. Gas sensing tests indicated that such hierarchical SnO 2 /Fe 2 O 3 heterostructures revealed improved acetone sensing performance compared to pure spindle-like Fe 2 O 3 , and the enhanced gas-sensitivity performance possibly be attributed to the synergistic effect and heterojunction of the interface between spindle-like Fe 2 O 3 and SnO 2 nanorod. Additionally, this research on as-obtained SnO 2 /Fe 2 O 3 hierarchical assembly may provide a new insight and a rational strategy to upgrade the sensing performance of certain semiconductor metal oxide materials by rationally designing various novel layered nanostructures in the future. [ABSTRACT FROM AUTHOR]

The fabrication of hybrid materials, such as SnO 2 -C, applicable in advanced energy storage systems, often suffers from lack of simplicity, scalability, cost effectiveness and/or sustainability. Therefore, the development of simpler and more efficient technologies for the sustainable production of energy materials with decent performance is highly desirable. In the current investigation, a hybrid nanostructured powder comprising of natural graphite flakes decorated with SnO 2 single crystalline nanorods (NG-SnO 2) was synthesized by a facile, rapid and cost effective one-step molten salt method, and characterized by a variety of techniques including X-ray diffraction, Raman spectroscopy, thermal analysis and electron microscopy. A perfect connection was identified between SnO 2 nanorods and few-layers graphite on the surface of flakes. This hybrid material exhibited an excellent electrochemical performance as the anode material for Li-ion batteries, delivering a reversible capacity of 495 mAhg−1 after 500 cycles. The few-layered graphite substrate could successfully promote the electron transfer kinetics and also buffers the mechanical stress caused by the lithiation-delithiation of perfectly attached SnO 2 nanorods during the battery cycling. The molten salt process discussed here provides a cost-effective and scalable strategy for rapid preparation of the hybrid nanostructured anode material, utilizing the low cost and abundant natural graphite. Image 1 • Efficient molten salt method for decoration of natural graphite with SnO 2 nanorods. • It is based on the oxidation of molten SnCl 2 on the surface of natural graphite. • The SnO 2 nano-single crystals anchored on hole-doped few layer graphene flakes. • The nanostructured hybrid material was characterized by various techniques. • Excellent electrochemical performance as anode material for Li-ion batteries. [ABSTRACT FROM AUTHOR]

Nanostructured SnO2/onion-like carbon (OLC) composites were fabricated via a facile and rapid microwave-assisted synthesis technique. The influence of SnO2 nanorods anchored on OLC was investigated as an anode material for the first time in lithium-ion battery applications. The OLC successfully served as a barrier layer between SnO2 nanorods and electrolyte to avoid the rupturing of the unstable SEI layer in order to provide improved coulombic efficiency, ionic resistance, and electronic conductivity. The SnO2 nanorod-OLC nanocomposite exhibits much stable and better electrochemical performance than pure SnO2 nanorods. The SnO2-OLC composite exhibited a remarkably high specific capacity of 884 mAh g−1 after 100 cycles with long-term cycling stability and excellent capacity retention of 93.5% (at current density of 100 mA g−1) with only 0.23% fading per cycle. The outstanding performance is attributed to the high surface area of OLC which can enhance electron transportation and high lithium-ion diffusion during cycling. [ABSTRACT FROM AUTHOR]

• Fe-doped BiVO 4 /SnO 2 composites were prepared via combining sol-gel and LPD processes. • Photocatalytic degradation of BR46 dye under visible-light irradiation was evaluated. • The 1.5Fe-BiVO 4 /SnO 2 nanocomposite exhibited the highest visible-light photoactivity. • Possible mechanism for the photocatalytic activity of nanocomposites was proposed. Designing and constructing heterogeneous structures is an effective approach employed to improve photocatalytic performance. This study aimed to use Fe-doped BiVO 4 /SnO 2 nanocomposites for photocatalytic degradation of Basic Red 46 (BR46) dye under visible-light irradiation. BiVO 4 nanoparticles doped with varying amounts of Fe were synthesized using the sol-gel method and interspersed on SnO 2 nanorods with an average diameter of about 100 nm fabricated using the liquid phase deposition (LPD) process. FE-SEM, EDX, XRD, FT-IR, XPS, BET, DRS, and PL analysis were used to characterize the morphology and structure of the samples. The 1.5 wt% Fe-doped BiVO 4 /SnO 2 nanocomposite exhibited the highest visible-light photoactivity with excellent stability, resulting in complete degradation of BR46 within 90 min of irradiation. The boost photocatalytic activity of Fe-doped BiVO 4 /SnO 2 nanocomposite can be attributed to the enhanced separation of photo-generated carriers derived from synergistic effects by the BiVO 4 /SnO 2 heterostructure, Fe doping in BiVO 4 lattice, and partly the extended light absorption ability. These findings show that designing a heterogeneous BiVO 4 /SnO 2 structure with Fe-doping can be a promising strategy for the application in constructing efficient and stable photocatalysts for the degradation of dyes from industrial wastewater pollutions. [Display omitted] [ABSTRACT FROM AUTHOR]

Graphical abstract 1D ultrafine SnO 2 nanorods anchored on 3D graphene aerogel (SnO 2 NRs/GA) composite is prepared through a simple reduction-induced self-assembly method. The unique 3D network structure as well as the synergistic effect between 3D graphene nanoshhet and 1D SnO 2 nanorods endows the as-prepared SnO 2 NRs/GA composite with the good electrochemical lithium/sodium storage performance. Abstract SnO 2 is considered as one of the most promising alternative anode materials for lithium ion batteries (LIBs) and sodium ion batteries (SIBs) due to high specific capacity, low discharge voltage plateau and environmental friendliness. In this work, 1D ultrafine SnO 2 nanorods anchored on 3D graphene aerogel (SnO 2 NRs/GA) composite is prepared through a simple reduction-induced self-assembly method in the solution of graphene oxide (GO), Vitamin C and SnO 2 nanoparticles. Vitamin C plays an important role in the reduction of GO. The structural and morphological characterizations demonstrate that 1D ultrafine SnO 2 nanorods are uniformly and tightly anchored on the surface of 3D graphene nanosheet aerogels. The unique 3D network structure as well as the synergistic effect between 3D graphene nanoshhet and 1D SnO 2 nanorods endows the as-prepared SnO 2 NRs/GA composite with the good electrochemical lithium/sodium storage performance. It delivers the high initial discharge capacity (1713 mA h g−1 at 0.1 A g−1 for LIBs and 539 mA h g−1 at 0.05 A g−1 for SIBs) and good cycle stability (869 mA h g−1 at 0.1 A g−1 after 50 cycles for LIBs and 232 mA h g−1 at 0.05 A g−1 after 100 cycles for SIBs). Moreover, the SnO 2 NRs/GA composite exhibits excellent cycle stability for SIBs with a high reversible capacity of 96 mA h g−1 at as high as 1 A g−1 for 500 cycles. This work provides a simple method to fabricate the electro-active materials-graphene aerogel composites for high-performance LIBs and SIBs. [ABSTRACT FROM AUTHOR]

Abstract: In this work, pure and Au‐nanoparticle‐decorated SnO2 nanorods were prepared via a one‐step hydrothermal method combined with a facile deposition process, and then characterized by X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, high‐resolution transmission electron microscopy, and X‐ray photoelectron spectroscopy. The xylene‐sensing performance of the nanorods was also investigated. The results show that Au nanoparticles with an average diameter of 4‐6 nm were immobilized on the surface of rutile SnO2 nanorods. As the amount of Au increased, the surface‐adsorbed oxygen species gradually increased. The 12 mol% Au‐SnO2 nanorods exhibited the highest response to 50 ppm xylene, a lower operating temperature (279 to 255°C), favorable selectivity, and fast response‐recovery speed (3 and 4 seconds, respectively). These properties made the fabricated nanorods good candidates for xylene detection. The possible mechanism for the enhanced xylene‐sensing performance is discussed. [ABSTRACT FROM AUTHOR]

Three-layered ZnO-CuO-SnO2 hybrid nanostructures n-p-n hetero-junctions were synthesized for the first time by 3-step chemical vapor deposition on SiO/Si substrates. Starting materials made of Cu, Zn and Sn powder mixed with carbon charcoal were heated at various temperatures and pressures under atmosphere of O2 and Ar. The prepared samples were investigated by field emission scanning electron microscope (FESEM), X-rays photoemission spectroscopy (XPS), and I-V characteristic curves. The results reveals the formation of CuO hollow microspheres with branching lines, ZnO nanowires, and SnO2 nanorods in which establish the three layers of the hetero-junctions. I-V characteristics exhibit rectifying behavior of hetero-layered semiconductors. [ABSTRACT FROM AUTHOR]

In this paper, pure and 1.5, 2.5 and 3.5 at.-% samarium oxide (Sm2O3) doped tin oxide (SnO2) nanorods were successfully synthesised with a facile and environment friendly hydrothermal process. All the as prepared nanostructures were carefully characterised by X-ray diffraction, field emission SEM, TEM, high resolution TEM and X-ray photoelectron spectroscopy respectively. Planar sensors were further fabricated with the as synthesised samples, and their sensing properties towards acetylene gas (C2H2), an extremely significant fault characteristic gas dissolved in oil immersed power transformers, were systematically measured. Interestingly, the sensing properties of the fabricated SnO2nanorod based sensor to C2H2gas can be obviously enhanced by adding Sm2O3, and the sensor doped with 3.5 at.-%Sm2O3displays the most superior sensing characteristics, including operating temperature, sensitivity, response and recovery time, etc., as compared to other three cases. All results indicate that the synthesised Sm2O3doped SnO2sensing material might be a promising candidate for C2H2sensing and lay a solid foundation for exploring high performance chemical gas sensor to detect C2H2gas extracted from power transformer oil. [ABSTRACT FROM AUTHOR]

The microstructure and composition of materials have significant impacts on the gas sensing performance of sensors. In this work, a well-constructed 1D SnO 2 nanorods/2D NiO porous nanosheets heterostructure were successfully prepared for the detection of ethanol gas. The SnO 2 nanorods with a diameter of 10–15 nm uniformly grew on the surface of NiO nanosheets, increasing the number of active sites. The space charge region formed at heterointerfaces controlled electron transfer, benefiting for improving sensor response. Gas test results showed that, at the optimum operating temperature of 300 °C, NiO/SnO 2 (Ni:Sn = 1:0.5) reached a high response of 25.7 to 100 ppm ethanol, which was about 15 times higher than pure NiO (1.65). In addition, the NiO/SnO 2 displayed a fast response-recovery speed, good selectivity, and excellent long-term stability. The enhanced gas sensing mechanism of NiO/SnO 2 was proposed by analyzing the surface chemical states, surface area, and electronic structure of materials. • 1D SnO 2 nanorods/2D NiO porous nanosheets p-n heterostructures were synthesized. • The SnO 2 nanorods were grown on NiO porous nanosheets for the detection of ethanol gas. • The SnO 2 /NiO heterostructures showed the highest responses and fastest response/recovery speed. • The enhanced gas sensing mechanisms of SnO 2 /NiO were proposed. [ABSTRACT FROM AUTHOR]

The world is facing alarming challenges of environmental pollution due to uncontrolled water contamination and multiple drug resistance of pathogens. However, these challenges can be addressed by using novel nanocomposites materials such as, SnO 2 /graphene nanopaletelets (GNPs) nanocomposites remarkably. In this work, we have prepared SnO 2 nanorods and SnO 2 /GNPs nanocomposites (GS-I and GS-II) with size of 25 ± 6 nm in length and 4 ± 2 nm in diameter. The optical bandgap energies change from 3.14 eV to 2.80 eV in SnO 2 and SnO 2 /GNPs nanocomposite. We found that SnO 2 /GNPs nanocomposite (GS-II) completely removes (99.11%) malachite green in 12 min, under UV light exposure, while under same conditions, SnO 2 nanorods removes only 37% dye. Moreover, visible light exposure resulted in 99.01% removal of malachite green in 15 min by GSII as compared to 24.7% removal by SnO 2 . In addition, GS-II nanocomposite inhibits 79.57% and 78.51% growth of P. aeruginosa and S. aureus respectively. A synchronized contribution of SnO 2 and GNPs makes SnO 2 /GNPs nanocomposites (GS-II) an innovative multifunctional material for simultaneous fast and complete removal of malachite green and inhibition of drug resistant pathogens., (© 2021 IOP Publishing Ltd.)

Photoelectrochemical (PEC) water splitting technology offers a sound strategy for the production of chemical energy using abundant solar energy. Herein, a ternary photoanode of SnO 2 /BiVO 4 /rGO was fabricated by plain chemical vapor deposition (CVD) and metal-organic decomposition followed by spin-coated rGO on the SnO 2 /BiVO 4 junction. The ternary photoanode yields the highest photocurrent density of 2.05 mA cm−2 at 1.23 V vs. RHE, which is 3.73 times of the BiVO 4 photoanode (0.55 mA cm−2). The incident photon-to-electron conversion efficiency (IPCE) of the ternary photoanode is 2.47 times that of the BiVO 4 photoanode at 400 nm, and the onset potential exhibits a cathodic shift of ∼300 mV. This enhancement can be attributed to the formation of n -n heterojunctions between the SnO 2 and BiVO 4 , and decoration of rGO on said heterojunctions because they synergistically improve the absorption of visible light, enhance the efficiency of charge separation , and accelerate electron transfer at the electrode/electrolyte interface. • SnO 2 /BiVO 4 /rGO photoanode was fabricated by facile method. • The SnO 2 /BiVO 4 /rGO photoanode is firstly reported in this study. • The photoanode achieves the photocurrent density of 2.05 mA/cm2 at 1.23 V vs RHE. • The enhancing mechanism is attributed to the heterojunction and decoration of rGO. [ABSTRACT FROM AUTHOR]

Here, a Sb-doped SnO 2 (ATO) nanorod underneath an α-Fe 2 O 3 nanorod sheathed with TiO 2 for photoelectrochemical (PEC) water splitting is reported. The experimental results, corroborated with theoretical analysis, demonstrate that the ATO nanorod underlayer effect on the α-Fe 2 O 3 nanorod sheathed with TiO 2 enhances the PEC water splitting performance. The growth of the well-defined ATO nanorods is reported as a conductive underlayer to improve α-Fe 2 O 3 PEC water oxidation performance. The α-Fe 2 O 3 nanorods grown on the ATO nanorods exhibit improved performance for PEC water oxidation compared to α-Fe 2 O 3 grown on flat fluorine-doped tin oxide glass. Furthermore, a simple and facile TiCl 4 chemical treatment further introduces TiO 2 passivation layer formation on the α-Fe 2 O 3 to reduce surface recombination. As a result, these unique nanostructures show dramatically improved photocurrent density (139% higher than that of the pure hematite nanorods)., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, the magnetic-dielectric core-shell heterostructure composites with the core of Ni submicron spheres and the shell of SnO2 nanorods were prepared by a facile two-step route. The crystal structure and morphology were investigated by X-ray diffraction analysis, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FESEM). FESEM and TEM measurements present that SnO2 nanorods were perpendicularly grown on the surfaces of Ni spheres and the density of the SnO2 nanorods could be tuned by simply varying the addition amount of Sn(2+) in this process. The morphology of Ni/SnO2 composites were also determined by the concentration of hydrochloric acid and a plausible formation mechanism of SnO2 nanorods-coated Ni spheres was proposed based on hydrochloric acid concentration dependent experiments. Ni/SnO2 composites exhibit better thermal stability than pristine Ni spheres based on thermalgravimetric analysis (TGA). The measurement on the electromagnetic (EM) parameters indicates that SnO2 nanorods can improve the impedance matching condition, which is beneficial for the improvement of electromagnetic wave absorption. When the coverage density of SnO2 nanorod is in an optimum state (diameter of 10 nm and length of about 40-50 nm), the optimal reflection loss (RL) of electromagnetic wave is -45.0 dB at 13.9 GHz and the effective bandwidth (RL below -10 dB) could reach to 3.8 GHz (12.3-16.1 GHz) with the absorber thickness of only 1.8 mm. By changing the loading density of SnO2 nanorods, the best microwave absorption state could be tuned at 1-18 GHz band. These results pave an efficient way for designing new types of high-performance electromagnetic wave absorbing materials.