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The exploration of non-noble-metal recyclable catalysts for high efficiency H2 generation from N2H4·H2O is of great significance for the sustainable strategy of society. A NiCo/NiO–CoOx ultrathin layered catalyst was fabricated successfully via a dynamics controlling coprecipitation–reduction (DCCR) process followed by calcination and applied to H2 generation from N2H4·H2O. Small nanosized NiCo particles (∼4 nm) were uniformly anchored on the surface of the NiO–CoOx ultrathin layered supports. Based on the cooperation between the NiCo active-centers and high intensity base-sites of the NiO–CoOx support, the Ni70Co30/NiO–CoOx ultrathin layered nanocomposite exhibits over 99% selectivity for H2 generation from N2H4·H2O with a high reaction rate (molN2H4 molNiCo−1 h−1) of 5.49 h−1 without using alkali as a catalyst promoter at 25 °C, which is superior to the reported studies. Moreover, the NiCo nanoalloys loading on the NiO–CoOx sheets enables an outstanding recycle performance over 10 cycles. The non-noble-metal NiCo/NiO–CoOx layered nanocomposite shows great value in catalyzing H2 generation from N2H4·H2O in practical applications. [ABSTRACT FROM AUTHOR]

New Cu2O-on-Cu nanowires (NWs) are constructed to develop the visible-light-driven activity of photocatalysts via the facile self-assembly of Cu2O nanoparticles (NPs) on a Cu NW surface assisted by a structure director, followed in situ reduction. In the resultant Cu2O-on-Cu NWs, the Cu2O NPs, with a diameter of 10 nm, show good distribution on the 50 nm-sized Cu single-crystal NWs. Owing to the band-gap adjusting effect and high electron transportation, the coupling of narrow-band-gap semiconductor Cu2O and excellent conductor Cu can lead to the markedly enhanced high visible light photocatalytic activity of Cu2O-on-Cu NWs toward the degradation of dye pollutants including Rhodamine B (RhB), methyl orange (MO) and methyl blue (MB). The as-designed Cu2O-on-Cu heterostructured NWs exhibit higher performance for the catalytic degradation of dye compounds than pure Cu2O. Nearly 60%, 100%, and 85% conversion with reaction rate constants (k) of 0.0137, 0.0746 and 0.0599 min−1 can be achieved for the degradation of RhB, MO and MB, respectively. Besides the highly efficient transportation of electrons, Cu NWs have a strong capacity for oxygen activation, which results in the gathering of negative charges and rich chemisorbed oxygen onto the surface. This may be responsible for the high catalytic efficiency of the Cu2O-on-Cu NWs toward the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Highly active Cu@ZnO brush-like nanostructures have been successfully synthesized through the heteroepitaxial growth process of ZnO branched nanorods (NRs) based on Cu core nanowires (NWs), and used for the evaluation of selective catalytic degradation for polycyclic aromatic compounds. The resultant Cu@ZnO nanobrushes, with the main diameter of ~500 nm, consist of Cu core NWs with diameter of ~50 nm and outer ZnO branch NRs shells with thickness of ~250 nm. The as-designed Cu@ZnO nanobrushes exhibit high performance for the selective catalytic degradation of polycyclic aromatic compounds. Nearly 90% conversion with the reaction rate constant (k) of 0.012 min-1 can be achieved for anthracene, while only about 50% and 10% conversions are shown for phenanthrene and naphthalene, respectively. Besides the highly efficient transportation of electrons, Cu NWs have strong capacity for oxygen activation which results in the gathering of negative charges and rich chemisorbed oxygen onto the surface, which is responsible for the high catalytic efficiency of Cu@ZnO nanobrushes toward the selective degradation of anthracene. [ABSTRACT FROM AUTHOR]

New Cu2O-on-Cu nanowires (NWs) are constructed to develop the visible-light-driven activity of photocatalysts via the facile self-assembly of Cu2O nanoparticles (NPs) on a Cu NW surface assisted by a structure director, followed in situ reduction. In the resultant Cu2O-on-Cu NWs, the Cu2O NPs, with a diameter of 10 nm, show good distribution on the 50 nm-sized Cu single-crystal NWs. Owing to the band-gap adjusting effect and high electron transportation, the coupling of narrow-band-gap semiconductor Cu2O and excellent conductor Cu can lead to the markedly enhanced high visible light photocatalytic activity of Cu2O-on-Cu NWs toward the degradation of dye pollutants including Rhodamine B (RhB), methyl orange (MO) and methyl blue (MB). The as-designed Cu2O-on-Cu heterostructured NWs exhibit higher performance for the catalytic degradation of dye compounds than pure Cu2O. Nearly 60%, 100%, and 85% conversion with reaction rate constants (k) of 0.0137, 0.0746 and 0.0599 min(-1) can be achieved for the degradation of RhB, MO and MB, respectively. Besides the highly efficient transportation of electrons, Cu NWs have a strong capacity for oxygen activation, which results in the gathering of negative charges and rich chemisorbed oxygen onto the surface. This may be responsible for the high catalytic efficiency of the Cu2O-on-Cu NWs toward the degradation of organic pollutants.