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The wide energy band and high recombination rate of photogenerated carriers severely limit the photocatalytic activity of TiO2. It has been demonstrated that ion doping can induce lattice defects, change the energy band structure, optimize the separation efficiency of photogenerated carrier, thus promoting the photocatalytic activity of the catalyst. In this work, Eu-doped TiO2 was synthesized by a sol–gel method, and the composition and photogenerated carrier separation efficiency of the samples were analysed by various characterization methods. The results show that Eu-TiO2 was successfully prepared and Eu-TiO2 exhibits higher photogenerated carrier separation efficiency and generates more superoxide radicals compared to the bare TiO2. Photocatalytic activity of the samples was evaluated by the degradation of Rhodamine B (RhB), and the results show that Eu doping improves the photocatalytic activity of the samples, the sample with Eu/Ti molar ratio of 0.2% displays 2.3-fold increase in photocatalytic activity compared to the blank TiO2. The improved photocatalytic activity can be attributed to the fact that Eu doping facilitates the effective separation of photogenerated carriers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rapeseed stem powder was employed to prepared OVs-BiOCl. • SP-BiOCl shows richer OVs than the reference BiOCl. • The separation rate of photo-generated carriers of RSP-BiOCl is largely enhanced. • RSP-BiOCl exhibits higher activity than the reference BiOCl. Construction of oxygen vacancies (OVs) is a reliable strategy to boost photocatalytic activity of a photocatalyst containing oxygen atom. OVs can accelerate the separation of photoinduced carriers, activate O 2 absorbed to yield ⋅O 2 –, elevating the photocatalytic activity. However, it is still a serious challenge to introduce plentiful OVs by a facile and wild channel. In this study, BiOCl with enriched OVs was successfully prepared with the assistance of rapeseed stem powder (RSP), which is an agricultural waste, achieving remarkably boosted photocatalytic activity toward removal of rhodamine B (RhB) and perfluorooctanoic acid (PFOA). The observations firmly confirm that the existence of RSP in the preparation system affects the crystal growth of BiOCl, induces abundant OVs, therefore, BiOCl prepared displays high specific surface area and separation rate of photoinduced carriers. Photocatalytic activity of RSP-BiOCl toward detoxification of RhB and PFOA is 3.47 times and 1.39 times of that of the blank BiOCl under visible light and UV light irradiation, respectively. RSP assisted-preparation is a solid approach to heighten the activity of BiOCl. [ABSTRACT FROM AUTHOR]

In this paper we investigate the effects of intravalley acoustic phonon scattering on the quantum transport and on the electrical characteristics of multigate silicon nanowire metal-oxide-semiconductor field-effect transistors. We show that acoustic phonons cause a shift and broadening of the local DOS in the nanowire, which modifies the electrical characteristics of the device. The influence of scattering on off-state and on-state currents is investigated for different values of channel length. In the ballistic transport regime, source-to-drain tunneling current is predominant, whereas in the presence of acoustic phonons, diffusion becomes the dominant current transport mechanism. A three-dimensional quantum mechanical device simulator based on the nonequilibrium Green’s function formalism in uncoupled-mode space has been developed to extract device parameters in the presence of electron–phonon interactions. Electron–phonon scattering is accounted for by adopting the self-consistent Born approximation and using the deformation potential theory. [ABSTRACT FROM AUTHOR]

• AgBr was prepared by a hydrothermal method with PVP. • Separation of photoactivated carriers has been largely promoted. • The level of •O 2 − was greatly boosted. • PVP-AgBr possess superior photocatalytic activity. In this paper, AgBr photocatalyst was prepared by a precipitation method using silver nitrate and potassium bromide as raw materials. The effects of polyvinylpyrrolidone (PVP) on the preparation and photocatalytic property of AgBr were investigated. The samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), surface photovoltage (SPS), ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS) and specific surface area (BET). Using rhodamine B as a model pollutant, photocatalytic performance of the photocatalyst prepared was tested under visible light irradiation. The results indicate that AgBr prepared by adding of PVP has superior photocatalytic activity. Under visible light irradiation, the destruction rate constant of rhodamine B (RhB) on PVP-AgBr is 4.79 times of that on the reference AgBr. [ABSTRACT FROM AUTHOR]

The improvement of subthreshold slope due to impact ionization is compared between “standard” inversion-mode multigate silicon nanowire transistors and junctionless transistors. The length of the region over which impact ionization takes place, as well as the amplitude of the impact ionization rate are found to be larger in the junctionless devices, which reduces the drain voltage necessary to obtain a sharp subthreshold slope. [ABSTRACT FROM AUTHOR]