This paper reports on a near zero band gap semiconductor, Ni x S y , which significantly enhances the photoluminescence (PL) performance of ZnO nanorods. The structural, morphological, and optical properties of the composites were characterized by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet–visible spectroscopy (UV–vis), PL spectrometry, etc. The PL patterns at an excitation wavelength (λex) of 325 nm revealed that the 10% Ni x S y /ZnO nanorod (10NZNR) composites displayed the highest emission intensity in the region of 420–630 nm. The relationship between the emission intensity of ZnO and the concentration of Ni x S y demonstrated that the PL intensity of NZNRs initially increased (<10%) and then declined with an increase in Ni x S y content (>10%). According to PL spectra at different excitation wavelengths and PL excitation (PLE) spectra, the visible emission of Ni x S y /ZnO nanorod (NZNR) composites can only be excited by light with energy greater than that of the band gap. Studies of the morphological structures and PL behaviors of NZNR composites have illustrated that Ni x S y considerably enhances the visible emission of ZnO by regulating its morphology and structure. An appropriate mechanism by which Ni x S y enhances the PL performance of ZnO has been proposed.

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Tunable mesoporous silica films were prepared though a sol-gel process directed by the self-assembly of various triblock copolymers. Positron annihilation γ-ray energy spectroscopy and positron annihilation lifetime spectroscopy (PALS) based on intense pulsed slow positron beams as well as ellipsometric porosimetry (EP) combined with heptane adsorption were utilized to characterize the open porosity/interconnectivity and pore size distribution for the prepared films. The consistency between the open porosities was examined by the variations of orthopositronium (o-Ps) 3γ annihilation fractions and the total adsorbed volumes of heptane. The average pore sizes deduced by PALS from the longest-lived o-Ps lifetimes are in good agreement with those by EP on the basis of the Barrett–Joyner–Halenda model, as indicated by a well fitted line of slope k = 1. The results indicate that the EP combined with heptane adsorption is a useful method with high sensitivity for calibrating the mesopore size in highly interconnected mesoporous films, whereas PALS is a novel, complementary tool for characterizing both closed and open pores in them.

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A ZnO/CdS/Cu2S composite photocatalyst with high photocatalytic activity was successfully synthesized by a three-step process. The results of XRD, XPS, SEM, and UV–Vis analysis show that ZnO nanosheets were successfully compounded with CdS nanoparticles, and the surface of CdS was successfully modified by Cu2S under ultraviolet light. Photocatalytic measurements were carried out and the results show that the photocatalytic efficiency of ZnO/CdS/Cu2S reached 95%. Compared with ZnO ([Formula: see text][Formula: see text][Formula: see text]), the kinetic constant of ZnO/CdS/Cu2S was up to [Formula: see text][Formula: see text][Formula: see text], which shows its excellent photocatalytic activity. A photocatalytic mechanism was proposed to illustrate the high activity separation efficiency.