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• IR-driven strong plasmonic coupling is achieved on a metal/non-metal heterostructure system consisting of Ag nanorices and W 18 O 49 nanowires. • Plasmonic coupling on Ag/W 18 O 49 heterostructure enhances the local electric fields with magnitudes of 101-104 times of that of incident light. • Resonance excitation not only induces ultrafast electron transfer from W 18 O 49 to Ag, but photothermal effect to increase local temperature. • Upon focused sunlight irradiation, the Ag/W 18 O 49 film shows a remarkable photo/thermal enhancement of catalytic activity for H 2 evolution. Plasmonic coupling between two or more metal nanostructures has attracted significant interest, since this fascinating near-field interaction is more effective for the aggregation/magnification of the incident light intensity compared to normal surface-plasmon-resonance (SPR) of single nanostructures. Herein, we report, for the first time, an IR-driven strong plasmonic coupling in an unusual metal/non-metal heterostructure system. This system is fabricated through random assemblage of Ag nanorices (NRs) onto W 18 O 49 nanowires (NWs) film with F-doped SnO 2 glass as substrate. Through the 3D-finite element simulation, we demonstrate that the plasmonic coupling between Ag NRs and W 18 O 49 NWs significantly enhances the localized electric fields at the "hot spots". This achieved magnitudes of 101-104 times of that of incident light, thus leading to the promoted generation of plasmonic "hot-electrons". Moreover, the resonance excitation of plasmonic coupling on the heterostructures not only induces ultrafast electron transfer from W 18 O 49 to Ag hetero-components, but also the photothermal effect to increase the localized temperature. Upon SPR-coupling excitation, the Ag/W 18 O 49 heterostructures film exhibits a remarkable enhancement of the photo/thermal catalytic activity for H 2 evolution from ammonia borane compared to that of either the Ag NRs (˜8.2 ×) or W 18 O 49 NWs (˜9.0 ×) films. Notably, we observed an obvious H 2 evolution over the Ag/W 18 O 49 heterostructures film under natural sunlight irradiation. [ABSTRACT FROM AUTHOR]

Plasmonic nanostructures have received significant attention in the field of solar-to-fuels conversion, because they can collect and utilize abundant low-energy photons to generate high-energy hot electrons for producing green chemical fuels. However, the ultrafast relaxation process of hot electron often leads to poor quantum yields of plasmonic nanostructures. Herein, we construct the one-dimensional W 18 O 49 /Carbon heterostructure for employing low-cost electrospun carbon fibers as the “electron mediator” to hinder the relaxation of hot electron in plasmonic W 18 O 49 nanowires. We confirm that the IR-excited plasmonic hot electrons in W 18 O 49 nanowires can quickly transfer to carbon fibers within only ∼50 fs in the W 18 O 49 /C heterostructure. This kinetics time is much shorter than the relaxation time of these hot electrons from high-energy surface plasmon (SP) to the ground state in W 18 O 49 nanowires (∼5.5 ps). As a result, upon low-energy IR-light excitation, the W 18 O 49 /C heterostructures exhibit nearly 2-fold enhancement on the catalytic H 2 production from ammonia borane as compared to single W 18 O 49 nanowires. Wavelength-dependent catalytic tests further indicate that this plasmon-enhanced catalytic activity is induced by the ultrafast transport process of plasmonic hot electron due to the localized surface plasmon resonance. [ABSTRACT FROM AUTHOR]

Abstract: One-dimensional 2,9,16,23-tetra-nitrophthalocyanine iron(II) (TNFePc)/TiO2 nanofiber heterostructures have been successfully obtained by a simple combination of electrospinning technique and solvothermal process. The as-obtained products were characterized by field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX) spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and IR spectrum. The results revealed that the TNFePc nanosheets were successfully grown on the primary TiO2 nanofibers. And, the coverage density of the secondary TNFePc nanostructures could be controlled by adjusting the experimental parameters. Photocatalytic tests displayed that the H2O2 assisted TNFePc/TiO2 nanofiber heterostructures (TNFePc/TiO2–H2O2) possessed a much higher degradation rate of methyl orange than the pure TiO2 and TNFePc/TiO2 nanofiber without H2O2 under visible light. Moreover, the TNFePc/TiO2 nanofiber heterostructures could be easily recycled without the decrease of the photocatalytic activity due to their one-dimensional nanostructural property of TiO2 nanofibers. [Copyright &y& Elsevier]

Abstract: The 3D open Bi2MoO6/ZnTiO3 hierarchical heterostructures with Bi2MoO6 ultrathin nanosheets (<10nm) grown on hexagonal-phase ZnTiO3 nanofibers were fabricated by combining the electrospinning technique and solvothermal method. And, the Bi2MoO6/ZnTiO3 hierarchical heterostructures had remarkable light absorption in the visible region. The photocatalytic studies revealed that the hierarchical heterostructures system exhibited exceptional photocatalytic activity in visible-light degradation of Rhodamine B, which might be attributed to the synergistic system with excellent charge separation characteristics and the unique morphology of Bi2MoO6 nanosheets with the extended absorption in the visible light region. What is more, the 3D open structure supported on nanofibrous candidates possessed large surface areas and excellent recyclability. [Copyright &y& Elsevier]

Abstract: Tin oxide (SnO2)/carbon nanofibers (CNFs) heterostructures were fabricated by combining the versatility of the electrospinning technique and template-free solvent–thermal process. The results revealed that the SnO2 nanostructures were successfully grown on the primary electrospun carbon nanofibers substrates. And, the coverage density of SnO2 nanoparticles coating on the surface of the CNFs could be controlled by simply adjusting the mass ratio of CNFs to SnCl4·5H2O in the precursor during the solvent–thermal process for the fabrication of SnO2/CNFs heterostructures. The electrochemical performances of the SnO2/CNFs heterostructures as the electrode materials for supercapacitors were evaluated by cyclic voltammetry (CV) and galvanostatic charge–discharge measurement in 1M H2SO4 solution. At different scan rates, all the samples with different coverage densities of SnO2 showed excellent capacitance behavior. And, the sample CS2 (the mass ratio of CNFs to SnCl4·5H2O reached 1:7) exhibited a maximum specific capacitance of 187F/g at a scan rate of 20mV/s. Moreover, after 1000 cycles, the specific capacitance retention of this sample was over 95%. The high capacitive behavior could be ascribed to the low resistance of SnO2/CNFs heterostructures and rapid transport of the electrolyte ions from bulk solution to the surface of SnO2. [Copyright &y& Elsevier]