Surface-enhanced Raman spectroscopy (SERS) represents a very powerful tool for the identification of molecular species, but unfortunately it has been essentially restricted to noble metal supports (Au, Ag and Cu). While the application of semiconductor materials as SERS substrate would enormously widen the range of uses for this technique, the detection sensitivity has been much inferior and the achievable SERS enhancement was rather limited, thereby greatly limiting the practical applications. Here we report the employment of non-stoichiometric tungsten oxide nanostructure, sea urchin-like W18O49 nanowire, as the substrate material, to magnify the substrate–analyte molecule interaction, leading to significant magnifications in Raman spectroscopic signature. The enrichment of surface oxygen vacancy could bring additional enhancements. The detection limit concentration was as low as 10−7 M and the maximum enhancement factor was 3.4 × 105, in the rank of the highest sensitivity, to our best knowledge, among semiconducting materials, even comparable to noble metals without ‘hot spots'.

Increasing interest has recently been devoted to developing small, rapid, and portable electronic devices; thus, it is becoming critically important to provide matching light and flexible energy-storage systems to power them. To this end, compared with the inevitable drawbacks of being bulky, heavy, and rigid for traditional planar sandwiched structures, linear fiber-shaped lithium-ion batteries (LIB) have become increasingly important owing to their combined superiorities of miniaturization, adaptability, and weavability, the progress of which being heavily dependent on the development of new fiber-shaped electrodes. Here, we report a novel fiber battery electrode based on the most widely used LIB material, titanium oxide, which is processed into two-dimensional nanosheets and assembled into a macroscopic fiber by a scalable wet-spinning process. The titania sheets are regularly stacked and conformally hybridized in situ with reduced graphene oxide (rGO), thereby serving as efficient current collectors, which endows the novel fiber electrode with excellent integrated mechanical properties combined with superior battery performances in terms of linear densities, rate capabilities, and cyclic behaviors. The present study clearly demonstrates a new material-design paradigm toward novel fiber electrodes by assembling metal oxide nanosheets into an ordered macroscopic structure, which would represent the most-promising solution to advanced flexible energy-storage systems.

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As a persistent organic pollutant, microplastics (MPs) have been reported to induce sperm quantity decrease in male rats. However, the related mechanism remains obscure. Therefore, this study is intended to explore the effects of polystyrene microplastics (PS-MPs) on male reproduction and its related mechanism of blood-testis barrier (BTB) impairment. Thirty-two adult male Wistar rats were divided randomly into four groups fed with PS-MPs for 90 days at the dose of 0 mg/d (control group), 0.015 mg/d, 0.15 mg/d and 1.5 mg/d respectively. The present results have showed that PS-MPs exposure led to the damage of seminiferous tubule, resulted in apoptosis of spermatogenic cell and decreased the motility and concentration of sperm, while the abnormality of sperm was elevated. Meanwhile, PS-MPs could induce oxidative stress and activate p38 MAPK pathway and thus deplete the nuclear factor erythroid-2 related factor 2 (Nrf2). Noteworthily, the adverse effect of PS-MPs on BTB is only signi cant in 0.15 mg/d and 1.5 mg/d groups ,which demonstrated that high-dose PS-MPs exposure may lead to the destruction of BTB integrity and the apoptosis of spermatogenic cells through the activation of MAPK-Nrf2 pathway. The current study provided novelty evidence for elucidating the effects of PS-MPs on male reproductive toxicity and its potential mechanism.