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Combustion synthesis has been widely used for low-temperature growth of metal-oxides nanomaterials. However, the mechanism behind its effectiveness remains unclear, because the current thermal analysis tools require the sample mass beyond 10 mg hardly achieved for nanomaterials. In this study, electrospinning was employed to fabricate massive In 2 O 3 nanowires network films that enables directly study the thermal behaviours of combustion in nanomaterials via thermal analysis tools. We compared the thermal behaviours of electrospun nanomaterials and bulk materials with/without combustion. In the absence of combustion reaction in both, the nanowires shows a lower decomposition temperature than the bulk (500 versus 570 °C). In the presence of combustion reaction in both, it shows even lower decomposition temperature than the bulk (430 versus 500 °C). These indicate that combustion synthesis has two-fold mechanisms: first, it indeed provides internal thermal energy through combustion reaction for crystallizing the nanowires; second, the large surface area of the nanowires promotes the gases transport, which in turn accelerate the decomposition of organics in the nanowires. Based upon both mechanisms, a field effect transistor made of In 2 O 3 nanowires network film was fabricated at 400 °C, whose I on /I off reaches up to 105 with an I on of 6 × 10−5 A. • Electrospinning was employed to fabricate massive In 2 O 3 nanowires that enables directly study the thermal behaviours of combustion in nanomaterials. • Combustion synthesis in nanomaterials has two-fold mechanisms: combustion reaction, and gases transport. • FET made of In 2 O 3 nanowires was fabricated at 400 °C, whose I on /I off reaches up to 105 with an I on of 6 × 10−5 A. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries (LSBs) are considered as one of the most promising energy storage devices owing to the high theoretical specific capacity and high theoretical specific energy, as well as natural abundance of sulfur. However, the soluble lithium polysulfide intermediates (LPSs) in electrolyte cause undesirable shuttle effect, resulting in the loss of sulfur and poor cycling stability. Herein, a novel tungsten oxide-decorated N, S co-doped carbon nanofibers (WO 3 @NS-CNFs) functional interlayer is applied to restrain the shuttle effect and enhance the cycling performance of LSBs. On the one hand, the uniformly distributed WO 3 can provide strong chemical anchoring sites for binding the LPSs and enhance the redox reaction kinetics. On the other hand, the NS-CNFs can also serve as the polysulfide trappers and enhance the electronic conductivity of sulfur electrodes. Therefore, benefiting from the synergy effect of WO 3 and NS-CNFs, the LSBs exhibit excellent cycling performance with a high initial capacity of 1444 mA h g−1 and reversible capacity of 1080 mA h g−1 after 100 cycles at 0.2 C, and superior rate capability of 946 mA h g−1 at 2 C. Image 1 • A novel WO 3 @NS-CNFs interlayer is firstly applied as anchor of polysulfides. • Synergistic WO 3 @NS-CNFs can inhibit shuttle effect and enhance redox kinetics. • The LSBs with WO 3 @NS-CNFs interlayers show remarkable electrochemical performance. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • SnO 2 /MO x (M=Zn, Ga, W) nanotubes and nanofibers were fabricated by one-step electrospinning and subsequent calcination. • Selectivity was effectively changed and controlled by designing various SnO 2 /MO x heterostructures. • SnO 2 /MO x sensors were firstly used to compose sensor arrays to detect VOCs mixtures by means of matrix manipulation. Abstract It is a challenge to effectively detect the components of a gas mixture using metal oxide sensors which are easily fabricated and inexpensive. In this work, heterostructured SnO 2 /MO x (i.e. M = Zn, Ga and W) nanotubes (NTs) and nanofibers (NFs) are synthesized via a one-step electrospinning technology and subsequent calcination for use in gas sensors. In specific, compared with pure SnO 2 NTs, SnO 2 /ZnO NTs show an enhanced response to 100 ppm ethanol and acetone, while SnO 2 /Ga 2 O 3 NTs show an obviously higher response to 100 ppm ethanol and SnO 2 /WO 3 NFs show an optimal response to 100 ppm xylene. All these sensors are selective in the presence of typically interfering gases such as formaldehyde, benzene and toluene. As a proof-of-concept, sensor arrays constructed using these three sensors precisely detected the gas mixtures of ethanol, acetone and xylene by means of matrix manipulation, delivering a superior accuracy of <9% deviation for the gas concentration of 10 ppm and 20 ppm and <38% for the concentration of 5 ppm. These results show the possibility of improved selectivity in detecting gas mixtures using heterostructured gas-sensing materials for sensor arrays. [ABSTRACT FROM AUTHOR]