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• The Ag 3 PO 4 /ZnO nanowires are fabricated by a simple two-step approach. • Ag 3 PO 4 /ZnO heterostructures exhibited excellent piezo-photocatalytic performance. • The p–n heterojunction and piezoelectric effect play effective role in the hotocatalysis. • Ag 3 PO 4 /ZnO nanowires exhibited excellent photodegradation for environmental pollutants. An imperative challenge emerged in the area of photocatalysis is the recombination of photoinduced electron–hole, which severely restricts the photodegradation efficiency of organic pollutants. This study proposes a piezoelectric Ag 3 PO 4 /ZnO nanowire with enhanced degradation performance of organic pollutants. The proposed nanowire can generate a piezoelectric effect under ultrasonic vibration to promote the separation and transfer of photoinduced carriers. The Ag 3 PO 4 /ZnO nanowires are fabricated by a simple two-step approach, and its structure and properties are tested by various methods. Results show that the Ag 3 PO 4 nanoparticles are attached on the surface of the ZnO nanowires, which endow the photocatalyst with enhanced absorption in the visible-light region. Photochemical and photoluminescence studies show that Ag 3 PO 4 /ZnO nanowires have good electron–hole pairs separation. Under light and ultrasonic radiation, Ag 3 PO 4 /ZnO nanowires (APZ-3) on a stainless steel mesh (3.0 × 3.0 cm, ~30 mg) show an optimum piezo-photocatalytic performance for MB with 98.16% degradation rate in 30 min. The reaction rate constants of piezo-photocatalytic Ag 3 PO 4 /ZnO nanowires (APZ-3) are 4.13 times of those conventional photocatalytic ZnO nanowires. In addition, the as-prepared sample is applied to the treatment of antibiotics in aqueous solutions, such as ciprofloxacin, norfloxacin, and ofloxacin, and achieves good degradation efficiency. The enhanced photocatalytic performance can be owed to the formation of the p–n heterojunction at the Ag 3 PO 4 /ZnO interface and the generation of the piezoelectric effect of ZnO nanowires in the degradation process. The results also demonstrate an economical way for practical applications in the degradation of organic pollutants at the industrial level. [ABSTRACT FROM AUTHOR]

MgO/TiO 2 (Degussa P25 TiO 2 ) composites were prepared and were used as visible-light-driven photocatalysts for the oxidation of aniline to nitrosobenzene under oxygen atmosphere. The typical sample with 5 wt% MgO loaded P25 (MP5) shows comparable photocatalytic activity with 2 wt% Pt/P25. The analyzed results of XPS indicate that the lattice oxygen in the MP5 possess higher electron density than those in P25. The electron-rich lattice oxygen, formed as a result of MgO loaded, would facilitate the deprontonation of aniline. A new peak at 3310 cm −1 was observed in in-situ FTIR spectrum for aniline adsorbed on the sample MP5, suggesting that anilino species were formed. These species may be produced via the deprontonation of aniline and result in the formation of the surface complexes. Further XPS studies for aniline adsorbed on the catalysts also indicate the existence of the surface complexes. Under visible light irradiation, the electrons may excite from the surface complexes and initiate the oxidation processes. Finally, speculated photocatalytic processes for the oxidation of aniline to nitrosobenzene were proposed at molecular level. [ABSTRACT FROM AUTHOR]

Solution processed multilayer organic light-emitting diodes (OLEDs) present challenges, especially regarding dissolution of the first layer during deposition of a second layer. In this work, we first demonstrated a plasma cross-linking technology to produce a solution processed OLED. The surfaces of organic films can be cross-linked after mixed acetylene and Ar plasma treatment for several tens of seconds and resist corrosion of organic solvent. The film thickness and surface morphology of emissive layers (EMLs) with plasma treatment and subsequently spin-rinsed with chlorobenzene are nearly unchanged. The solution processed triple-layer OLED is successfully fabricated and the current efficiency increases 50% than that of the double-layer OLED. Fluorescent characteristics of EMLs are also observed to investigate factors influencing the efficiency of the triple-layer OLED. Plasma cross-linking technology may open up a new pathway towards fabrication of all-solution processed multilayer OLEDs and other soft electronic devices. [ABSTRACT FROM AUTHOR]

A novel adsorbent NH 2 /MCM-41/NTAA, capable of simultaneous adsorption of cations and anions from aqueous solution, was prepared by immobilization of amine and nitrilotriacetic acid anhydride (NTAA) onto MCM-41. The structures and properties before and after surface modification were systematically investigated through X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM), nitrogen adsorption–desorption, and infrared spectroscopy (FTIR), thermogravimetry (TGA) and X-ray photoelectron spectroscopy (XPS). They together confirm that the amine and NTAA group were chemically bonded to the internal surface of the mesoporous. The NH 2 /MCM-41/NTAA were used to adsorb Pb 2+ and MnO 4 − in an aqueous solution in a batch system, and the maximum adsorption efficiency was found to occur at pH 5.0 and 3.0, respectively. NH 2 /MCM-41/NTAA exhibit preferable removal of Pb 2+ through electrostatic interactions and chelation, whereas it captures MnO 4 − by means of electrostatic interactions. The experimental data are fitted the Langmuir isotherm model reasonably well, with the maximum adsorption capacity of 147 mg/g for Pb 2+ and of 156 mg/g for MnO 4 − . The adsorption rates of both Pb 2+ and MnO 4 − are found to follow the pseudo-second order kinetics. Furthermore, the NH 2 /MCM-41/NTAA adsorbent performs good recyclability and reusability for 5 cycles use. This study indicates a potential applicability of NH 2 /MCM-41/NTAA as new absorbents for effective simultaneous adsorption of hazardous metal ions and anions from wastewater. [ABSTRACT FROM AUTHOR]

A novel, bifunctional mesoporous silica (Al-SBA-15-G) capable of the simultaneous removal of cations and anions from wastewater was synthesized by the incorporation of aluminum into the framework of SBA-15 followed by the immobilization of melamine-based dendrimer groups onto the surface of the Al-substituted SBA-15. This material was characterized by XRD, SEM, TEM, NH 3 -TPD, FTIR, and N 2 adsorption/desorption. The bifunctional Al-SBA-15-G contains a large amount of aluminum hydroxyl groups and amine groups, which were considered to be responsible for the formation of cation and anion complexes, respectively. Due to the steric effects of the melamine-based dendrimer groups, the aluminum hydroxyl and amine groups on Al-SBA-15-G keep an appropriate distance with a cooperative manner and avoid spontaneous neutralization reactions. The maximum adsorption capacities toward Cu 2+ and SO 4 2− of Al-SBA-15-G were 0.763 mmol/g and 0.511 mmol/g, respectively. A mechanism for the simultaneous adsorption of cations and anions by Al-SBA-15-G is proposed. As a bifunctional adsorbent, Al-SBA-15-G can potentially be used for the simultaneous removal of cations and anions from wastewater. [ABSTRACT FROM AUTHOR]

Photothermal synergistic and Ni modification dramatically changed the electron transfer behavior of CO 2 (ads) and H 2 (ads) via regulating Fermi level. [Display omitted] • Photothermal synergistic changed the electron transfer behavior of CO 2 adsorption. • Photothermal synergistic and NiO X cause the formation of Ni0 and Vos-Nb sites.. • Ni modification changed the electron transfer behavior of H 2 adsorption. • CO 2 molecules may form dimer CO 2 · CO 2 δ− species on Vos-Nb sites. • CO 2 hydrogenation is affected by electron transfer behavior of CO 2 /H 2 adsorption. Thermo-driven photocatalytic CO 2 hydrogenation is studied for NiO x /Nb 2 O 5 from the point of CO 2 and H 2 adsorption behavior. Photothermal synergistic and Ni modification dramatically changed the electron transfer behavior of CO 2 adsorption (CO 2 (ads)) and H 2 (ads) via regulating Fermi level and providing Ni0 and V O s adsorption sites, respectively. The H 2 (ads) at Ni0 site donates electrons to NiO x /Nb 2 O 5 (pre-oxidized) and CO 2 (ads) at V O s-Nb5+ or Ni0 site accepts electrons from NiO x /Nb 2 O 5 (pre-reduced), while NiO x /Nb 2 O 5 displayed excellent photocatalytic activities. Furthermore, in situ DRIFTS results suggested that CO 2 (ads) will form two reaction pathways: (1) CO 2 (ads) at Ni0 site directly hydrogenated with H atoms (H 2 molecule dissociates at Ni0 to form two H-atoms) to generate CH 4 and C 2 H 6 through COOH intermediate; (2) CO 2 (ads) form dimer CO 2 · CO 2 δ− species at V O s-Nb5+ site, and it will be further disproportioned to produce CO and CO 3 δ− species, then CO 3 δ− species are gradually hydrogenated to form CH 4 and C 2 H 6. Moreover, increasing the number of CO 2 /H 2 molecules accepts/donates electrons will also improve the reduction degree of CO 2. This work offers a new explanation for photothermal synergistic. [ABSTRACT FROM AUTHOR]

The nano-TiO 2 samples with different morphologies were prepared for visible-light-driven photocatalytic selective oxidation of benzylamine and the role of active sites between morphologies and photocatalytic performances was discussed. [Display omitted] • Three types of anatase nano-TiO 2 with different morphologies were prepared for visible-light-driven photocatalytic selective oxidation of benzylamine. • The surface properties of the samples were systematically studied by various characterization techniques. • Coordinatively unsaturated Ti atoms can chemisorb and activate benzylamine molecules via forming H-N ... Ti coordination species. • Oxygen vacancies can chemisorb and activate oxygen molecules to form reactive oxygen species. • The role of active sites between morphologies and photocatalytic performances was discussed. Enormous efforts have been devoted to exploring the influence of the materials' morphology on photocatalytic performance, while the role of active site between them attracts less attention. Herein, three types of anatase nano-TiO 2 with different morphologies were successfully prepared for visible-light-driven photocatalytic selective oxidation of benzylamine. The material properties of the samples were systematically studied by various characterization techniques such as XRD, SEM, TEM, AFM, XPS, UV–vis DRS, ESR and in situ FTIR. Due to possessing clear advantages especially for having more active sites (coordinatively unsaturated Ti atoms and oxygen vacancies), the TiO 2 with porous structure shows more excellent photocatalytic performance than the other samples. Coordinatively unsaturated Ti atoms can chemisorb and activate benzylamine molecules via forming H-N ... Ti coordination species, whose absorption property of visible light guarantees that TiO 2 samples can achieve the photocatalytic process under visible light. Oxygen vacancies can chemisorb and activate oxygen molecules to form reactive oxygen species (superoxide radical) by the reduction of photogenerated electrons. Finally, a possible synergetic mechanism based on the interaction of reactants and catalyst interfaces was proposed at the molecular level to illustrate the photocatalytic process. [ABSTRACT FROM AUTHOR]