Evidence is found for corrosion-induced open-volume defects, presumably related to hydrogen, in deeper parts of the material below the corrosion layer.A NaI-promoted sequential double carbon-sulfur bond formation was developed to afford sulfur-bridged imidazopyridines, using Deoxofluor as the sulfur source and requiring only 15 min at room temperature. Using this process, imidazo[1,5-a]pyridines could also be transformed to 1,2,4-thiadiazoles in the presence of ammonium salt with the formation of both carbon-sulfur and nitrogen-sulfur bonds. This mechanistically unique method is distinguished by its wide substrate scope, lack of requirement for transition metals and mild conditions.Although numerous doubly positively charged diatomic molecules (diatomic dications) are known from investigations using mass spectrometry and ab initio quantum chemistry, only three of them, NO2+, N22+ and DCl2+, have been studied using rotationally resolved optical spectroscopy and only about a dozen by vibrationally resolved double-ionization methods. selleckchem So far, no thermodynamically stable diatomic dication has been characterized spectroscopically, primarily because of experimental difficulties associated with their synthesis in sufficient densities in the gas phase. Indeed, such molecules typically involve, as constituents, rare-gas, halogen, chalcogen, and metal atoms. We report here on a new approach to characterize molecular dications based on high-resolution photoelectron spectroscopy of the singly charged parent molecular cation and present the first spectroscopic characterization of a thermodynamically stable diatomic dication, MgAr2+. From the fully resolved vibrational and partially resolved rotational structures of the photoelectron spectra of 24MgAr+ and 26MgAr+, we determined the potential-energy function of the electronic ground state of MgAr2+, its dissociation (binding) energy (D0 = 10 690(3) cm-1), and its harmonic (ωe(24MgAr2+) = 327.02(11) cm-1) and anharmonic (ωexe(24MgAr2+) = 2.477(15) cm-1) vibrational constants. The analysis enables us to explain quantitatively how the strong bond arises in this dication despite the fact that Ar and Mg2+ both have a full-shell rare-gas electronic configuration.Assembly of nanowires into three-dimensional macroscopic aerogels not only bridges a gap between nanowires and macroscopic bulk materials but also combines the benefits of two worlds unique structural features of aerogels and unique physical and chemical properties of nanowires, which has triggered significant progress in the design and fabrication of nanowire-based aerogels for a diverse range of practical applications. This article reviews the methods developed for processing nanowires into three-dimensional monolithic aerogels and the applications of the resultant nanowire aerogels in many emerging fields. Detailed discussions are given on gelation mechanisms involved in every preparation method and the pros and cons of the different methods. Furthermore, we systematically scrutinize the application of nanowire-based aerogels in the fields of thermal management, energy storage and conversion, catalysis, adsorbents, sensors, and solar steam generation. The unique benefits offered by nanowire-based aerogels in every application field are clarified. We also discuss how to improve the performance of nanowire-based aerogels in those fields by engineering the compositions and structures of the aerogels. Finally, we provide our perspectives on future development of nanowire-based aerogels.A facile method to produce an MXene-TiO2 composite is demonstrated for enhanced field emission display applications. The field emission performance of two-dimensional free-standing and linear-shaped field emitters has been systematically investigated and enhanced electron emission behaviors (e.g. emission current, stability and emission patterns) are achieved by compositing MXene and TiO2 nanowires. The relationship between the emission current density, electric field and anode-cathode gap distance is studied and the emitters, especially the cross-section of the composite film, show good performance. The emission current from the cross-section of the composite film can reach 289 mA cm-2, which is the best result of the state of the art compared to single MXene and TiO2 nanowires. We have also reported a triboelectric nanogenerator powered by free-standing MXene-TiO2 composite emitters, implying the feasibility of the self-powering field emission devices and possibly enlarging the applications of cold emitters in various fields.In this work, we present the construction of a multilayered PtSe2/Ge heterostructure-based photodetector array comprising 1 × 10 device units operating in the short-wavelength infrared (SWIR) spectrum region. The as-fabricated heterostructures show an obvious photovoltaic effect, providing the devices with the ability to work as self-driven photodetectors. Upon 1550 nm illumination, a typical photodetector exhibits prominent photoresponse performance with the current on/off ratio, responsivity, external quantum efficiency and specific detectivity reaching 1.08 × 103, 766 mA W-1, 61.3% and 1.1 × 1011 Jones, respectively. The device also has a fast response speed with rise/fall times of 54.9 μs/56.6 μs. Thanks to the respectable homogeneity in device performance, the photodetector array can reliably record an image of a “diode symbol” produced by SWIR irradiation. What is more, the photodetector is successfully integrated into a SWIR optical communication system serving as an optical receiver to transmit a text signal. The above results imply a huge possibility of the present heterostructure-based photodetector array for some optoelectronic purposes such as SWIR image sensing and optical communication applications.An enhanced photothermal signal detection method based on graphene oxide (GO) integrated long period fiber grating (LPFG) for on-site sodium copper chlorophyllin (SCC) quantification is proposed. SCC, as a porphyrin compound, can be photonically excited to induce a stronger photothermal effect. GO offers superior molecular adsorption and thermal conductivity properties; depositing it on the LPFG surface significantly improves the sensitivity and detection efficiency of the SCC photothermal signal, when irradiated with a 405 nm laser. The experimental results showed improved performance compared with those from uncoated LPFG, with a sensitivity of 0.0587 dB (mg L-1)-1 and a limit of detection (LOD) of 0.17 mg kg-1, which is also an order of magnitude lower than that of traditional high-performance liquid chromatography. The proposed method has potential applications in the fields of real-time food safety monitoring, environmental pollutant detection, and disease diagnosis.