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[Display omitted] • Porous and hollow 1D SnO 2 /Zn 2 SnO 4 composites are prepared by electrospinning. • UV light enhanced excellent TEA gas-sensing property can be primarily observed. • Greatly reduced working temperature of 120 °C and superior selectivity are gained. • Good practicality of gas sensors for food spoilage evaluation is valuable. • Enhanced mechanism is derived from the accelerated surface electron migration. Porous and hollow SnO 2 /Zn 2 SnO 4 composites with typical one-dimensional (1D) structure have been synthesized by adjusting the amounts of 2-methylimidazole zinc salt (ZIF-8) added in the precursor solution through a modified electrospinning technology. Compared with the gas-sensing performance of different samples detected in the normal condition, it is confirmed that the optimal working temperature can be markedly decreased from 260 to 120 °C under UV light irradiation, along with the substantially improved gas selectivity. In addition, SnO 2 /Zn 2 SnO 4 heterostructures exhibit a higher response (increases from 1.7 to 2.8) and faster response/recovery times (decreases from 24/154 to 14/42 s) to triethylamine (TEA) than that of the pure SnO 2. Significantly, the good practicality of gas sensors for food spoilage evaluation could be testified by effectively detecting the gas released during the putridity of prawns. UV light enhanced surface electron migration mainly contributes to the elevated synergistic effect between the formation of n-n heterojunction and tunable surface/interface electron transport behavior, as well as the adsorption and desorption of TEA molecules on the surface of the sensing materials. [ABSTRACT FROM AUTHOR]

Synopsis: A sustainable approach for the synthesis of noble-metal-free MoS 2 /Zn 0.5 Cd 0.5 S heterostructures with W/Z phase junctions with enhanced visible-light-driven photocatalytic hydrogen evolution and stability is reported. [Display omitted] • The noble-metal-free MoS 2 /Zn 0.5 Cd 0.5 S with W/Z phase junctions were prepared successfully. • Appropriate MoS 2 modification can enhance the separation efficiency of the charge carriers. • The 3%MoS 2 /Zn 0.5 Cd 0.5 S showed optimal visible-light photocatalytic hydrogen production. • The ESR spectra indicated that O 2 – and h+ played a major role during the degradation process. • The enhanced photocatalysis ascribed to interfacial optimization of double heterojunction. A series of composite heterojunction-MoS 2 /Zn 0.5 Cd 0.5 S photocatalysts free of noble metal ions was prepared using a simple hydrothermal method. The X-ray diffraction spectra of the MoS 2 /Zn 0.5 Cd 0.5 S composites exhibit three strong intensive peaks, thereby explaining the existence of wurtzite (CdS) and zinc blende (ZnS) in the form of the wurtzite/zinc-blende phase junctions. Microstructural studies indicate that the sample displays a typical cubic crystal structure and that the MoS 2 with flower-like structure uniformly wraps the granular Zn 0.5 Cd 0.5 S. X-ray photoelectron, Fourier transform infrared, and UV–Vis diffuse reflectance spectroscopic methods confirm that the heterojunction, which possesses outstanding photoresponse ability, is constructed between Zn 0.5 Cd 0.5 S nanoparticles and MoS 2 nanoflowers. The fluorescence spectroscopy, surface photocurrent spectroscopy, and electrochemical studies indicate that Zn 0.5 Cd 0.5 S nanoparticles with specific amount of MoS 2 nanoflowers can effectively suppress the recombination of photoinduced charge carriers of the composites. Therefore, pristine Zn 0.5 Cd 0.5 S nanoparticles loaded with 3%MoS 2 exhibit optimum performance of hydrogen production (388.2 μmol/h), which is 1.3 times that of pristine Zn 0.5 Cd 0.5 S nanoparticles. A plausible mechanism for enhanced photocatalysis is provided in terms of the heterojunction assisted effective separation of charge carriers that are generated by irradiation. [ABSTRACT FROM AUTHOR]