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The artificial stacking of nanohybrid films helps to enhance their properties and thus intrigues researchers to explore this possibility in emerging technologies. The layer-by-layer approach was used to fabricate samples of zinc sulfide/reduced graphene oxide (ZnS/rGO) by using spin coating technique. The structure and optoelectronic properties has been extensively studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), UV-VIS-NIR spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Hall measurements. Raman spectrum elucidates the phonon contribution of ZnS and breathing mode of κ-point phonons and sp2 bonds of carbon atoms of rGO. The electron-phonon interactions reveal reduction in electron mobility and enhancement in holes contribution with rGO content leading to surface charge transfer doping (SCTD). XPS results explain the valence band edge and conduction band edge to form type-I band alignment to reconfirm carrier-type reversal. A change in the dispersion of refractive indices along with a small rise in the value of absorption coefficient in terahertz (THz) region for ZnS/rGO nanocomposite films has been observed. These results will open up new opportunities to furthering the science of this technologically important class of materials for future electronics.The fabrication of flexible electronic sensors with self-healing capability is of great importance for the applications in wearable devices and skin-like electronics. Herein, a molybdenum disulfide (MoS2) nanosheets-based hydrogel (Gel-PEG-MoS2, GPM hydrogel), with near infrared (NIR) light-induced self-healing property, was first reported as a flexible sensor. Only a small amount of MoS2 nanosheets (0.04 wt‰) could impart the hydrogel with fast self-healing property under NIR irradiation in 90 s. The healing efficiencies increased with the increasing of MoS2 loadings. Moreover, the GPM hydrogel exhibited both contact and noncontact sensing properties based on its deformation-dependent and light-sensitive conductivity, showing potential application as mechanical sensor and light-activated switches. By employing the versatile MoS2 nanosheets, the hydrogel exhibited both fast self-healing ability and mechanical/light sensing capability. Therefore, the MoS2-based hydrogel provides a two-pronged approach for construction of self-healing flexible electronics.Reducing the material size could be an effective approach to enhance the electrochemical performance of porous carbons for supercapacitors. In this work, ultra-fine porous carbon nanofibers are prepared by electrospinning using lignin/ polyvinylpyrrolidone as carbon precursor and zinc nitrate hexahydrate (ZNH) as an additive, followed by pre-oxidation, carbonization, and pickling processes. selleckchem Assisted by the ZnO template, the pyrolytic product of ZNH, abundant micropores are yielded, leading to the formation of microporous carbon nanofibers with specific surface area (SSA) up to 1363 m2 g-1. The average diameter of the lignin-based ultra-fine porous carbon nanofibers (LUPCFs) is effectively controlled from 209 to 83 nm through adjusting the ZNH content. With good flexibility and self-standing nature, the LUPCFs could be directly cut into electrodes for use in supercapacitors. High accessible surface, enriched surface N/O groups, and reduced fiber diameters endow the LUPCFs-based electrodes with an excellent specific capacitance of 289 F g-1. The reduction of fiber diameters remarkably improves the rate performance of the LUPCFs and leads to a low relaxation time constant of 0.37 s. The high specific capacitance of 162 F g-1 is maintained when the current density is increased from 0.1 to 20 A g-1. Besides, the fabricated LUPCFs show exceptional cycling stability in symmetrical supercapacitors, manifesting a promising application prospect in the next generation of supercapacitors.Currently, carbon-based catalysts integrated with macroporous catalytic membrane have aroused considerable attention for environmental remediation because of its practicability and high efficiency. Herein, nitrogen doped carbon nanotube hybrids (Fe-Co@NC-CNTs) decorated with multiple active species (Fe3Co7/CoFe2O4@Fe/CoNC) were designed through N-molecule assisted pyrolysis of bimetallic (Fe/Co) metal-organic frameworks, and then immobilized on poly(vinylidene fluoride) (PVDF) membrane to construct macroporous Fe-Co@NC-CNTs/PVDF catalytic membrane via directional freezing technique, where active sites were efficiently exposed for oxidants and target pollutants. As expected, Fe-Co@NC-CNTs/PVDF membrane successfully achieved almost 100% bisphenol A (BPA) degradation after 40 min via PMS activation, which was significantly overperformed the majority of conventional carbon-based catalysts. Besides, we found that Fe-Co@NC-CNTs/PVDF membrane not only exhibited ideal catalytic and self-cleaning property in humic acid (HA)-BPA coexistence system, but also maintained the excellent reusability and ultrahigh water flux (10464.45 L m-2 h-1) even after 5 cycles. Notably, in EPR analysis and quenching experiments, it was found that sulfate radicals (SO4·- and ·OH) and singlet oxygen (1O2) participated the degradation process while 1O2 made a major contribution. More significantly, this study is very meaningful for the development of novel catalytic self-cleaning membranes with PMS activation.Carbon-supported single-atom catalysts (C-SACs) demonstrate great potential in various key electrochemical reactions. Nevertheless, the development of facile and economical strategies is highly appealing yet challenging given that the commonly used pyrolysis method has strict requirements on the structure and composition of precursors. Here, we demonstrate for the first time a facile and low-cost pyrolysis strategy assisted by molten salts at high temperature for preparing porous C-SACs with well-dispersed Co-N4 sites directly from a Chlorella precursor. Based on the X-ray absorption fine structure results and aberration-corrected scanning transmission electron microscopy images, we show that single atom Co-N4 moieties are anchored on a carbon matrix. A porous structure with a large specific surface area (2907 m2 g-1) and atomically dispersed active sites of Co provide the as-prepared Co-N/C-SAC with excellent electrocatalytic activity and stability for the ORR. The electrochemical measurements show that the half-wave potential and limited current density of this material are 0.

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