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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]

[Display omitted] • In situ growth of porous WO 3 /FeWO 4 hierarchical structure is originally obtained. • The distribution of p-n heterojunctions is dependent on the content of MIL-101. • The optimal operating temperatures to n-butanol can be reduced from 220 to 25 °C. • Efficient heterojunction interfaces gain surface electronic structure modulation. • A strategy of novel room temperature n-butanol-sensing performance is presented. This study originally reports the in-situ construction of porous WO 3 /FeWO 4 ribbon-like hierarchical composites with unique and intense heterojunction interface behavior and the enhanced adsorption and carrier transport capability for effectively detecting n-butanol at room temperature. The introduction of different adding amounts of MIL-101 plays the key role of the morphological evolution of WO 3 -based microstructures with the well-distributed nanoparticles in situ growth on the surface by a facile electrospinning and subsequent calcination process. Compared with pristine WO 3 , a sharp and useful reduction of the optimal operating temperature from 220 to 25 °C can be observed as the Fe component increasing, mainly owing to the inverted p-type gas sensitive response caused by the controllable variable of FeWO 4 phase in the multiple effective WO 3 -FeWO 4 heterojunctions. The optimal WO 3 /FeWO 4 composites can display the highest response of 12.3 and a relatively short response/recovery times of 110/140 s to 100 ppm n-butanol at 25 °C, together with the superior gas selectivity, repeatability, humidity and long-term stability. Density functional theory (DFT) simulation is employed for verifying the significant adsorption interaction and charge transfer between n-butanol molecule and WO 3 /FeWO 4. Regular distribution of WO 3 -FeWO 4 heterojunction interfaces can not only determine the collaborative modulation of electronic structures, but also provide the efficient surface/interface transport mechanism for MIL-101 induced one-dimensional (1D) hierarchical ribbons. Actually, the integrated gas-sensitive components based on WO 3 /FeWO 4 composites exhibit the rapid response characteristic under room temperature condition and provide a friendly strategy of optimizing the practical detection of ppm-level n-butanol for other inorganic heterogeneous sensors. [ABSTRACT FROM AUTHOR]

Currently, the construction of three-dimensional (3D) flower-like SnS 2 /In 2 S 3 heterostructures has been primarily developed for low-temperature gas-sensing detection of triethylamine (TEA) by a facile hydrothermal treatment. The thickness of nanosheets and the number of folds of self-assembled products can be well regulated as the introduction of In component increasing, as well as the distribution of effective SnS 2 –In 2 S 3 heterojunctions. All the as-prepared SnS 2 -based sensors can exhibit good gas sensitive response behavior to TEA at various low operating temperatures, even for the first time at room temperature. For example, the optimal SnS 2 -1% In have the highest response (21.01), the relatively fast response/recovery times, and superior gas selectivity and stability to 100 ppm TEA at 40 °C, compared with other samples. Besides the combination of the formation of SnS 2 –In 2 S 3 heterojunctions, abundant active sites of the self-assembled structures, and unique surface/interface transmission mechanism is beneficial to the enhanced gas-sensing performance, significantly, the generation of state density resonance effect can be employed for improving the electron transport efficiency due to the adjustment of state density near the Femi level. The available long-term, cycling, and humidity stabilities and the linear response relationship of the sensors greatly contribute for the potential application of seafood storage evaluation. • Flower-like SnS 2 /In 2 S 3 self-assembly with effective heterojunctions is obtained. • SnS 2 -based sensors can exhibit superior TEA-sensing behavior at low temperatures. • Available state density resonance effect plays the key role of sensing behavior. • SnS 2 /In 2 S 3 sensors can be used for the application of seafood storage evaluation. • Construction of new TEA sensors with state density resonance effect is provided. [ABSTRACT FROM AUTHOR]