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Abstract Here we demonstrate a simple, rapid for the controlled synthesis of core-shell structural graphite coated TiO 2 nanoparticle (TiO 2 @G), which are directly prepared by detonation chemical decomposition of the gas-liquid mixture of CH 4 , O 2 , C 6 H 6 and TiCl 4 in milliseconds. Various techniques, including XPS, TEM, XRD and Raman were employed to investigate the products. It is found that the sphere, good disperse mixed crystal TiO 2 nanoparticles with crystal size of 10–30 nm were coated with thick graphite layers. Based on Zeldovich Neuman-Doring (ZND) model, the detonation synthesis mechanism of core-shell structure TiO 2 @G is discussed. This rapid synthesis method can be extended to the preparation of other core-shell materials. Graphical abstract Schematic diagram of TiO 2 @G nanoparticles growth. Unlabelled Image Highlights • Core-shell structure TiO 2 @G was prepared by a gas-liquid detonation methods. • The influence of carbon-free, carbon-low and carbon-rich environment on the coating structure was discussed. • The growth mechanism of the TiO 2 @G was discussed using ZND model. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the gaseous mixture (CH 4 , C 2 H 2 , H 2 and O 2) and ferrocene were used as raw materials to rapidly synthesize core-shell structure carbon/graphite encapsulated iron-based nanoparticles under high-temperatures and high-pressure environment generated by gaseous-liquid detonation. The obtained black powders were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) with selected area electron diffraction (SAED) and Raman spectroscopy. The results indicated that the uniformly sized (10–50 nm) iron-based core-shell structural composite nanoparticles were effectively synthesized by adjusting the mole ratios of mixture gaseous. In addition, the growth mechanism of carbon/graphite encapsulated metal nanoparticles was also discussed based on the ZND model theory. Graphical abstract Schematic diagram of carbon/graphite encapsulated iron base nanoparticles growth. Unlabelled Image Highlights • Core-shell structure C/GEMNPs were prepared by a gaseous-liquid detonation methods. • The main affecting factors of different coated nanocrystals were discussed. • The growth mechanism of the C/GEMNPs was discussed using ZND model. [ABSTRACT FROM AUTHOR]

Abstract: Carbon-encapsulated iron-based nanoparticles with a core–shell structure were produced by detonation decomposition of explosive mixture precursors containing iron ion components. The size and magnetic properties of the as-prepared composite particles were revealed by X-ray powder diffraction, transmission electron microscopy and magnetic measurements. Results showed that the different sizes of the iron-based nanocrystal core and the thickness of the carbon shell could be yielded by adjusting the component materials of the explosive precursors during the course of these detonation chemical reactions. The composite particles had a body-centered cubic iron or iron carbide core with a coating of graphitic or amorphous carbon layers. Magnetic measurements indicated these composite nanoparticles were magnetic at the room temperature, with some variation in the values of saturation magnetization, remanences and coercive forces that depend on the size and grain composition. [ABSTRACT FROM AUTHOR]

Abstract: Synthesizing carbon-encapsulated ferronickel nanoparticles was developed by a detonation method. The composite precursors were ignited in the nitrogen in closed explosion vessel. These composite nanoparticles were characterized with transmission electron microscope, energy-dispersive X-ray spectrometer, X-ray diffraction, X-ray fluorescence, Raman spectroscopy and magnetic measurement. Results indicated that carbon-encapsulated ferronickel nanoparticles with diameters ranging from 10 to 50nm were produced and the composite nanoparticles were with a core–shell structure. The composite nanoparticles were synthesized with the yield about 10–15% one time. [ABSTRACT FROM AUTHOR]

Carbon nano-onions (CNOs) were synthesized in a few milliseconds by a detonation method using a gas-liquid mixture as the precursor. The composition, morphology and microstructure of products were studied by TEM, XRD, Raman and XPS. Furthermore, the four-ball tests were carried out to investigate the tribological properties of CNOs as lubricant additives. The results showed that the CNOs consisting of spherically concentric graphitic shells with a narrow size distribution about 15.8 nm, which plays the role of "micro bearing" in mechanical lubrication. From the four-ball tests, the friction coefficient and wear scar diameter become slighter and uniform with the addition of CNOs to the base lubricant. When the content of CNOs is about 0.06 wt%, there are minimum frictional coefficient and wear scar diameter. Schematic illustration of the formation mechanism of CNOs. Unlabelled Image • One-step gas-liquid detonation synthesis of carbon nano-onions • The spherical or ellipsoidal shape CNOs with an average size of 15.8 nm • The tribological properties of CNOs as lubricant additives investigated • The minimum frictional coefficient/wear scar diameter with 0.06 wt% CNOs [ABSTRACT FROM AUTHOR]

Al 2 O 3 anchored carbon quantum dots/TiO 2 nanorods (Al/C/TNRs) achieved high and stable photoelectrochemical performances under solar light, and could provide efficient photocathodic protection for Q235 CS in marine environment. • CQDs modified TiO 2 nanorods (CQDs/TiO 2) were fabricated for solar-driven photocathodic protection property of Q235 carbon steel. • Alumina ultrathin layer deposited by ALD technology is used for enhancing the photoelectrochemical stability of CQDs/TiO 2. • The composite displayed improved photoelectrochemical performances under solar light. • The composite has charge storage ability to maintain photocathodic protection for seven hours in dark. A new photoanode of Al 2 O 3 anchored carbon quantum dots/TiO 2 nanorods (Al/C/TNRs) was constructed for efficient photocathodic protection of Q235 carbon steel (CS) by hydrothermal treatment and ALD process. The Al/C/TNRs photoanode achieved a photocurrent density of 2.28 mA/cm2 under simulated sunlight (AM 1.5 G), and could maintain for 7 days nearly without decay. Potential of Q235 CS was negatively shifted by 620 mV after coupling with Al/C/TNRs in 3.5 wt% NaCl solution, and could maintain more than 7 h. The high and stable photoelectrochemical performances of Al/C/TNRs indicate potential photocathodic protection for Q235 CS in marine environment. [ABSTRACT FROM AUTHOR]