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[Display omitted] • The influence of C/N dual-doping in MoS 2 based sputtered films was investigated. • The lamellar structure of MoS 2 was maintained with high doping level and low S/Mo. • The balance between mechanical properties and lubricating performance was achieved by adjusting the content of C/N dopants. Transition metal dichalcogenides (TMDs) show poor mechanical properties and weak corrosion and oxidation resistance in ambient atmosphere, which results in the limit application and the lower work life. Doping TMDs based films with the enhanced performance show the potential to apply in harsh environment. The C/N dual-doping Mo-S-C-N films were deposited by magnetron sputtering, and the evolution of alternative microstructure composed of TMDs phase and amorphous inclusions was analyzed. The enhancement on mechanical, tribological and anti-corrosion properties of films with C/N dual-doping were evaluated. The strengthened TMDs phase and inclusions with MoC x /MoN x hard phase result in the improvement of mechanical properties (hardness 8.57–19.09 GPa). The superior tribological performance was obtained from film with 10.67 at. % of C and 17.36 at. % of N (wear rate 8.24 × 10-7 mm3/Nm, average friction coefficient (CoF) 0.188) and film with 14.87 at. % of C and 15.02 at. % of N (wear rate 8.02 × 10-7 mm3/Nm, average CoF 0.166). The balance between the effect of lubricating phase and mechanical performance strengthen by C/N dopants were achieved in these two films. The passivation of reactive sites in MoS 2 leads to the improvement of corrosion resistance, while excessive dopants induce more pathways for corrosive medium, which leads to the corrosion failure of films. [ABSTRACT FROM AUTHOR]

[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]

Abstract: In the present study, we succeeded in accelerating the L10 ordering transition of FePt thin films by employing amorphous Ni–Al as underlayers. The coercivity H c =5kOe and ordering parameter S =0.67 of FePt thin films deposited on a Ni–Al underlayer with a thickness of ∼5nm after 380°C annealing for 30min are significantly higher than those H c =0.4kOe and S =0.35 of the films without the Ni–Al underlayer. The L10 ordering process of and the coercivity of FePt thin films can be significantly tuned by varying the thickness of the Ni–Al underlayer. [Copyright &y& Elsevier]

• Hierarchical C-N/Co/Ti composite derived from MOF/TBOT precursor is obtained. • Structure consists of dodecahedron-like particles covered with twisted nanotubes. • Ti and Co are effectively separated in the upper and lower ends of nanotubes. • C-N/Co/Ti eletrocatalyst exhibits superior ORR properties than that of Pt/C. • Novel mechanism is ascribed from the phase composition and microstructure. C-N/Co/Ti composites derived from ZIF-67@TiO 2 precursors have been fabricated by a facile thermal treatment process. The morphology and composition are highly dependent on the available parameters inferring of exact hydrolysis of tetrabutyl titanate and sintering temperature. The obtained hierarchical microstructure is composed of numerous dodecahedron-like hollow boxes decorated with in-situ growth of size-tunable and twisting nanotubes on surfaces. The effective elemental separation of Ti and Co on the upper and lower ends of nanotubes can be realized by regulating the ionic migration and crystalline phase formation process at a high temperature. The as-prepared C-N/Co/Ti composites exhibit the enhanced electrocatalytic activities to oxygen reduction reaction (ORR) via a favorable four-electron pathway and the desired reaction kinetics with the low Tafel slope (67.8 mV dec−1), as well as the excellent methanol tolerance in comparison with the Pt/C electrocatalysts. The superior ORR electrocatalytic performance would be mainly contributed to the combination of the designed multi-phase composition, the enhanced surface adsorption/desorption, the modified surface/interface electron transfer mechanism, and the constructed Co/Ti double-active sites on different locations of microstructure. The present work presents a new insight for the synthesis of C-N-based inorganic composite with outstanding electrocatalytic behavior for ORR process. [ABSTRACT FROM AUTHOR]