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[Display omitted] • Low temperature TEA-sensing SnS 2 /MnS microflowers are originally fabricated. • DFT simulation shows the transformation from semiconductive to metallic nature. • SnS 2 /MnS-3 % exhibits high responses of 17.85/23.67 to 100 ppm TEA at 30/40 ℃. • The enhanced metallicity plays a vital role of the enhanced gas-sensing behavior. • New strategy for gaining effective sulfide RT gas-sensing materials is presented. The development of low-temperature SnS 2 -based sensitive elements with unique surface adsorption and transport regulation for triethylamine (TEA) has always been an intractable challenge. In the present work, ultrathin SnS 2 /MnS microflowers with enhanced metallicity have been prepared by a facile one-step hydrothermal method, which is especially beneficial for achieving superior TEA-sensing performance under room temperature (RT) condition. Compared with pure SnS 2 , the SnS 2 /MnS-3 % can obviously exhibit higher responses of 17.85 and 23.67, faster response/recovery times of 165/506 and 156/344 s, and the enhanced gas selectivity and stability to 100 ppm TEA at 30 and 40 ℃, respectively. Taking account of density functional theory (DFT) calculation, the transformation of SnS 2 -based sensors from semiconductive to metallic nature plays a critical role of the enhanced gas-sensing behavior with the increased gas molecules absorption and electron transport efficiency, which can provide a new strategy for constructing novel and effective sulfide RT gas-sensing composites. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • SnS 2 /ZIF-8 derived porous flower-like SnO 2 /ZnO heterostructures were obtained. • New self-assembled SnS 2 flower-like microstructures were used as templates. • SnO 2 /ZnO composites exhibit high sensitivity and selectivity to TEA at 200 °C. • Tunable morphology and n–n heterojunctions play a key role for gas sensing property. • The method can be used for obtaining other heterostructures with novel shapes. Abstract SnO 2 -based flower-like sensitive materials derived from the self-assembled SnS 2 microstructures with more active areas and less agglomeration represent an alternative option for new generation of gas sensors. Meanwhile, the introduction of ZIF-8 for semiconductor surface functionalization is expected to get multi-functional hybrid materials with synergistic effects of individual components. In the present work, SnS 2 /ZIF-8 derived porous flower-like SnO 2 /ZnO heterostructures have been synthesized by a facile template method and the subsequent heat-treatment process. Beside the uniform morphology with tunable composition and size distribution, the attractive findings are focused on the enhanced triethylamine (TEA) gas-sensing properties of the obtained composites. SnO 2 /ZnO heterostructures show an obvious improvement in TEA gas sensing performance at the operating temperature of 200 °C, giving a response of about 17.7–50 ppm TEA, which was about 2.2 times higher than that of the sensors based on pure SnO 2. [ABSTRACT FROM AUTHOR]

The coal-based energy production in China generates more than 600 million tons of coal fly ash (CFA) each year, which drives us searching for new methods for recycling CFA. In this work, continuous glass fibers with a range of CFA (25–45%) were successfully prepared without showing any sign of fiber crystallization. The measured fiber tensile strength was found to increase with CFA proportionally. The fiber derived from 45% CFA exhibited the best tensile strength (higher than the E glass fiber prepared/tested under the same conditions) and good chemical stability (98% mass retention in the acid corrosion test). Our study shows a feasibility of making continuous CFA derived glass fibers with high iron oxide content and an alternative way for CFA recycling. Its improved strength and good chemical durability can benefit both economy and environmental protection. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cubic-like In 2 O 3 /α-Fe 2 O 3 composites assembled with porous nanoplates are obtained. • The introduction of Fe3+ component plays a vital role for morphological evolution. • In 2 O 3 /α-Fe 2 O 3 composites display superior TEA gas-sensing behavior at 170 °C. • In/Fe-2 shows the highest response and excellent cycling and long-term stability. • Sensing mechanism mainly depends on the unique microstructure and heterojunction. Cubic-like In 2 O 3 /α-Fe 2 O 3 heterostructures assembled with 2D porous nanoplates have been prepared by solvothermal method and subsequent calcination process. The introduction of Fe3+ component plays an important role for the morphological evolution of In 2 O 3 -based samples with unique crystal nucleation and growth mechanism. Compared with flower-like In 2 O 3 self-assemblies composed of tower-like structural units, In 2 O 3 /α-Fe 2 O 3 composites can display superior trimethylamine (TEA) gas-sensing behavior. For example, the optimal working temperature is reduced from 250 to 170 °C, and the response value of In/Fe-2 materials is 375.43, which is about 6.23 times than that of In 2 O 3 sensors. The enhanced gas-sensing properties are mainly attributed to large specific surface area (234.4 m2/g), the effective In 2 O 3 -α-Fe 2 O 3 heterojunctions, unique surface/interface effects, and tunable electron transmission mechanism. [ABSTRACT FROM AUTHOR]

• ZIF-67-induced double-tubular 1D CeO 2 /Co 3 O 4 heterostructures were obtained. • The variation from nanobelt to double-tubular shape relies on the amount of ZIF-67. • Samples show high specific surface area and superior photocatalytic property of MB. • Unique morphology and heterojunction cause electron transfer synergetic mechanism. • Double-tubular CeO 2 /Co 3 O 4 composite can be a promising photocatalyst for MB. ZIF-67-induced double-tubular 1D CeO 2 /Co 3 O 4 heterostructures have been prepared by an electrospinning method with tunable morphological evolution mechanism. As the adding amount of ZIF-67 increasing, the morphologies of CeO 2 -based nanomaterials are changed from porous granular nanobelt to smooth curly shape, and finally formed a double-tubular structure. The optimal CeO 2 /Co 3 O 4 products consisting of well-dispersed double-tubular nanostructure with the external diameter of about 200 nm display high specific surface area of 196.05 m2g−1 and superior photocatalytic performance of methylene blue (MB). The rapid degradation rate of 97% within 40 min and high cycling stability without significant decrease of photocatalytic activity could be attributed to the unique electron transfer synergetic mechanism based on the combination of double-tubular microstructure and CeO 2 /Co 3 O 4 heterojunctions. [ABSTRACT FROM AUTHOR]

• Flake-like K 2 Co 3 (P 2 O 7) 2 ·2H 2 O (KCoPi) was prepared by a hydrothermal method. • The as-prepared KCoPi features a layered structure and zigzag chains of CoO 6. • The KCoPi nanoflakes exhibit remarkable OER activity in alkaline solution. Alkali metal cobalt phosphates show great potential as electrocatalysts for oxygen evolution reaction (OER). Herein, a kind of layered potassium cobalt pyrophosphate dehydrate, i.e., K 2 Co 3 (P 2 O 7) 2 ·2H 2 O, was prepared by a simple hydrothermal method, and was proved to be a novel OER electrocatalyst for the first time. The as-developed K 2 Co 3 (P 2 O 7) 2 ·2H 2 O features a layered structure, large specific surface area, and special zigzag CoO 6 octahedral chains, all of which contribute to the highly efficient OER performance. In specific, it achieves 10 mA cm−2 at an overpotential of only 296 mV and a Tafel slope of 40.2 mV dec−1 in 1.0 M KOH. Thus, this present work has opened a new pathway to develop alkali metal cobalt phosphates towards efficient and stable electrocatalytic oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

• Plasma functionalized carbon cloth is prepared. • Oxygen containing functional groups formed on the carbon cloth surface. • The functionalized carbon cloth exhibits a great enhancement of OER activity. • Acceleration of surficial proton transfer probably enhances the OER activity. This paper reports a simple and facile method to prepare surface functionalized commercial carbon cloth via a plasma treatment and its application in electrocatalytic oxygen evolution reaction (OER). It is observed that abundant oxygen containing functional groups formed on the surface of the treated carbon cloth. The functionalized carbon cloth (FCC) exhibits a remarkable of OER activity. Specifically, it can drive a current density of 10 mA cm−2 at a fairly low overpotential of 360 mV and a correspondent small Tafel slope of 66.7 mV dec−1. More unexpectedly, it was found that the OER activity of FCC follows the non-concerted proton-coupled electron transfer mechanism. A possible explanation was proposed that the surface carboxyl groups improve the proton-transfer kinetics, accelerating the deprotonation from OOH to OO* during the OER process. [ABSTRACT FROM AUTHOR]

Uniform bead-like CuMn 2 O 4 /ZnO nanofibers were successfully fabricated via a facile electrospinning technology. The current new findings can be emphasized on the introduction of ZIF-8 into Cu-based precursor solution that had a great significance for controlling phase structure and morphology of CuMn 2 O 4 /ZnO composites. Compared with hollow CuMn 2 O 4 nanofibers and CuMn 2 O 4 /ZnMn 2 O 4 irregular rod-like materials, CuMn 2 O 4 /ZnO nanofibers can display the enhanced photocatalytic efficiency of 86% as the irradiation time increasing to 50 min and the good photocatalytic cycle stability to methylene blue (MB). The influence of adding amount of ZIF-8 on the morphological evolution and photocatalytic property of CuMn 2 O 4 /ZnO nanofibers and the relevant photocatalytic mechanism were investigated. The synthesis approach of CuMn 2 O 4 /ZnO nanofibers is expected for fabricating other 1D semiconductor composites with novel morphologies and advanced properties in photocatalysis, gas sensing, and electrochemical applications. [ABSTRACT FROM AUTHOR]

Morphology-controlled porous α-Fe 2 O 3 /SnO 2 nanorods with uniform surface heterostructures have been fabricated by a facile surface modification of rod-like α-Fe 2 O 3 nanomaterials by changing the adding amount of Sn composition, displaying the excellent selectivity and sensitivity of gas-sensing to acetone. The introduction of SnO 2 nanoparticles had the great effects on tuning the crystal size, crystallinity, and surface status, as well as the structural stability and phase distribution of α-Fe 2 O 3 /SnO 2 nanorods. Compared to pure α-Fe 2 O 3 , α-Fe 2 O 3 /SnO 2 heterostructures can exhibit the optimal gas-sensing behavior with the sensitivity up to 53.1 and the response and recovery times decreasing to 9 and 2.5 s at the operating temperature of 260 °C, respectively. The enhanced gas-sensing performance can be mainly attributed to the combination of uniform porous structures, narrow size-distribution, large specific surface area, and heterostructures of the interface between α-Fe 2 O 3 and SnO 2 . [ABSTRACT FROM AUTHOR]

The highly-dispersed carambola-like SnO 2 /C composite microparticles have been fabricated through a novel electrospun approach using tetrobutylammonium bromide and paraffin liquid as functional additives in the precursor solution. The presence of carbon matrix can availably contribute for the reduced agglomeration, decreased migration, and controllable sizes of SnO 2 nanocrystals. The influence of calcination temperature on the microstructures and photocatalytic properties of SnO 2 /C products and the relevant photocatalytic mechanism were investigated. The carambola-like SnO 2 /C photocatalysts showed the superior photocatalytic performance for the degradation of rhodamine B (RhB) with the high efficiency of 94.6% as the irradiation time increasing to 210 min as well as the good photocatalytic cycle stability. The preparation technology can be potentially applied for adjusting microstructures of other inorganic oxide photocatalysts in the field of water treatment. [ABSTRACT FROM AUTHOR]

• Nanoflakes-assembled 3D flower-like nickel hydroxidenitrate was synthesized. • The flower units of as-prepared NiNH composed of ultrathin porous nanosheets. • The as-prepared NiNH exhibits remarkable OER activity in alkaline solution. This paper reports a nanoflakes-assembled 3D flower-like nickel hydroxidenitrate (NiNH) and its application in water oxidation. It is demonstrated for the first time that the NiNH is an efficient oxygen evolution reaction (OER) electrocatalyst in alkaline solution. Specifically, it can drive a current density of 10 mA cm−2 at a fairly low overpotential of 280 mV and a correspondent small Tafel slope of 39.6 mV dec−1. The impressive OER catalytic activity of the as-prepared NiNH can be ascribed to its favorable 3D hierachical microstructure. The present research not only provide us a prospective and cost-effective electrocatalyst for water splitting but also affords us an inspiration for designing effective transition-metal based electocatalysts through microstructure regulation. [ABSTRACT FROM AUTHOR]

Abstract: V2O5 macro-plates have been prepared using water/ethanol media. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The as-prepared V2O5 plates appear to be an orthorhombic structure, and they seem to be composed of strip-like V2O5 nanocrystals which appear to be parallel or perpendicular to each other. The band gap of the V2O5 macro-plates calculated from the optical absorption edge is about 3.4 eV, showing a strong blue shift compared to bulk V2O5. It is also found that the final shape of the V2O5 macro-plates strongly depends on the reaction conditions. The possible formation mechanism of the V2O5 macro-plates is discussed. [Copyright &y& Elsevier]