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Abstract: Nanocarbon–metal oxide hybrids are among the most promising functional materials in many cutting‐edge environmental and energy applications where efficient charge separation and extraction are keys to success. The next level of hybrid structures will be achieved once one learns how to control and tune charge/energy transfer processes at the interfaces. However, little is yet known about the nature and extent of these interfacial dynamics in nanocarbon hybrids. Here a model is designed in which ultrathin dielectric layers (Al2O3, ZrO2) between the hybrid's components (ZnO, TiO2) and carbon nanotubes allow for evaluating and tuning of interfacial charge transfer over an unusually long distance of at least 50 nm. Surprisingly, the transfer efficiency correlates linearly with the barrier layer thickness, indicating that electron conduction through the barrier layer constitutes the rate‐limiting step. It is also demonstrated that the charge transfer efficiency can be tuned by the type of interlayer and its degree of crystallinity, thus controlling the hybrid's performance in the photocatalytic production of hydrogen. It is believed that this model system will help to understand and decipher the fundamentals regarding interfacial charge and energy transfer in nanocarbon hybrids with the aim to further advance these hybrid structures for a wide range of energy applications. [ABSTRACT FROM AUTHOR]

The article reports on the usage of the dual excitation transient photo-current measurement (DETPM) for differentiating bolometric effect in Nanocarbon-inorganic hybrids. Topics discussed include increase in the concentrations of carbon nanotubes (CNTs) and graphene, usage of Photoluminescence (PL) for monitoring of PL quenching, requirement of the charge separation. Particular focus is given on the usage of the Transient photocurrent measurements (TPM).

Abstract: We investigate how residual catalyst from carbon nanotube (CNT) templates can be used to engineer novel functional nanomaterials. CNTs, produced via continuous flow chemical vapour deposition, typically contain catalyst residues in the form of encapsulated metal clusters or of iron oxide nanoparticles attached to the outside of the CNTs. These CNTs are used as sacrificial templates for TiO2 coatings using benzyl alcohol as a linking agent. Upon oxidation of the CNTs, the encapsulated iron particles dissolve into the TiO2 lattice and form iron-doped TiO2 nanotubes without the formation of secondary phases, while the iron oxide particles merely attach to the outer surface. The materials show extended light absorption into the visible range, a requirement for visible-light photocatalyst. [Copyright &y& Elsevier]

The article focuses on the properties and application of carbon nanotubes (CNTs)-inorganic hybrids, a new type of hybrid materials developed from CNTs. It states that this kind of functional material replaces the organic compound with CNTs and combines the multiphase characteristics of nanocomposites with hybrid frameworks' functions. It projects that it has the capacity to trap electrons and reduce the rate of electron-hole recombination in some applications such gas sensors and photovoltaics.

Single‐walled carbon nanotubes (SWCNTs) with a mean diameter of 1.4 nm are filled with rubidium iodide. The filling of nanotubes is proved by high‐resolution scanning transmission electron microscopy. The chemical composition of the filler is confirmed by X‐ray photoelectron spectroscopy (XPS). The electronic properties of the filled SWCNTs are studied by XPS and Raman spectroscopy. The encapsulated salt leads to n‐doping of nanotubes. The detailed multifrequency Raman spectroscopy investigation of the alteration of Raman modes of SWCNTs upon filling is conducted. The doping‐induced changes in the radial breathing mode and G‐band are revealed. It is found that these changes differ for the metallic and semiconducting SWCNTs. The obtained data and revealed trends are expected to be helpful for forthcoming studies to interpret the observed changes in Raman spectra of filled metallic and semiconducting SWCNTs. [ABSTRACT FROM AUTHOR]

We have investigated the electronic properties of single-walled carbon nanotubes (SWCNTs) filled with lead chloride, lead bromide (PbBr2) and lead iodide (PbI2). The filling of SWCNTs and formation of encapsulated one-dimensional nanocrystals of the salts were directly confirmed by high-resolution scanning transmission electron microscopy. The chemical composition of the encapsulated nanocrystals was proven by X-ray photoelectron spectroscopy (XPS). The electronic properties of the filled SWCNTs were characterized by Raman spectroscopy and XPS. All the three lead halogenides result in p-doping of SWCNTs and, consequently, there is a downshift of the SWCNTs' Fermi level due to the charge transfer towards the salts. The effect is stronger with metallic than semiconducting nanotubes. The efficiency of doping depends on the type of lead halogenide. The doping effect is the strongest for PbI2 and the weakest for PbBr2. [ABSTRACT FROM AUTHOR]

Abstract: Hybridizing carbon nanotubes with complex inorganic nanostructures provides a new route to designing next-generation photocatalysts. These hybrids utilize charge transfer processes through the interface, which reduce the electron–hole recombination rate in the photocatalyst. This work presents the first complex CNT hybrid, using titanium-silicate (TS-1), with dramatically improved photocatalytic activity for the degradation of organic compounds compared with the corresponding nanocomposite and the individual components. [ABSTRACT FROM AUTHOR]