The construction of lattice-matched CdS-AgS heterojunction photocatalysts: High-intensity built-in electric field effectively boosts bulk-charge separation efficiency.

The built-in electric field of heterojunction can effectively promote carrier separation and transfer. While, its interface orientation is often random, leading to lattice mismatch and high resistance, thus limiting the efficiency of interfacial charge transfer. Herein, the lattice-matched heterojunction (CdS-AgS) was constructed by ion-exchange epitaxial growth.

Construction dual vacancies to regulate the energy band structure of ZnInS for enhanced visible light-driven photodegradation of 4-NP.

Most of the intrinsic photocatalysts with visible light response can only generate one active radical due to the limitation of their band structures, which is immediate cause limiting their photocatalytic degradation performance. In this work, ZnInS with Zn vacancy and S vacancy (V-ZnInS) was prepared for the first time. As expected, the V-ZnInS exhibits remarkable photocatalytic performance for 4-Nitrophenol (4-NP) degradation under visible light and the apparent rate constant is about 11 times that of pristine ZnInS.

Fabrication of ZnAl-LDH mixed metal-oxide composites for photocatalytic degradation of 4-chlorophenol.

In this work, two different types of ZnAl-layered double hydroxide (LDH) mixed metal-oxide composites (CeO and SnO) were synthesized and applied for the photodegradation of 4-chlorophenol (4-CP) in wastewater. The fabricated CeO/ZnAl-LDH and SnO/ZnAl-LDH were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, UV-visible diffuse reflectance spectroscopy (UV-vis DRS), and theoretical density functional theory (DFT) calculations, suggesting that the band gaps of the synthesized hybrid composites were much lower than those of traditional ZnAl-LDH. In addition, the photocatalytic activity for 4-CP degradation and reaction kinetics were investigated to evaluate the catalytic behavior of the prepared composites.

3D hollow BiO@CoAl-LDHs direct Z-scheme heterostructure for visible-light-driven photocatalytic ammonia synthesis.

In this paper, the novel 3D hollow Z-scheme heterojunction photocatalysts based on BiO and CoAl layered double hydroxides (BiO@CoAl-LDHs) were prepared for efficient visible-light-driven photocatalytic ammonia synthesis. The synthesized nanohybrid exhibits excellent photocatalytic ammonia synthesis performance (48.7 μmol·L·h) and structural stability, which is primarily attributed to the fact that Z-scheme heterojunction significantly enhanced lifetime of photogenerated carriers (6.

Direct Z-scheme CeO@LDH core-shell heterostructure for photodegradation of Rhodamine B by synergistic persulfate activation.

Photocatalytic activation of persulfate (PAPS) is considered an efficient and green approach for the mitigation of organic pollutants because of its advantages in low energy consumption and high reusability of photocatalysts. Herein, direct Z-scheme CeO@LDH heterojunction photocatalyst with a core-shell structure is constructed. We reveal that CeO@LDH exhibits excellent persulfate (PS) activation performance and high degradation efficiency of RhB under visible light irradiation.

A low-temperature water-gas shift reaction catalyzed by hybrid NiO@NiCr-layered double hydroxides: catalytic property, kinetics and mechanism investigation.

The realization of a high efficiency water gas shift reaction (WGSR) at low temperatures has always been a research hotspot and is difficult to achieve. Based on NiCr layered double hydroxides (NiCr-LDHs), a hybrid NiO@NiCr-LDH was prepared by intercalation and surface complexing. The above materials were applied to WGSR at low temperatures, and the catalytic activity and reaction mechanism of WGSR with NiCr-LDHs and LDHs intercalated with organic metal ligands (NiCr-Ni/SB-LDHs) were compared.

Visible light promoted degradation of gaseous volatile organic compounds catalyzed by Au supported layered double hydroxides: Influencing factors, kinetics and mechanism.

In this paper, factors of initial concentration, catalyst dosage, irradiation intensity, relative humidity and reaction temperature onto visible light gaseous o-xylene photodegradation by ZnCr layered double hydroxides (ZnCr-LDHs) and Au supported ZnCr-LDHs (Au/ZnCr-LDHs) were investigated. ZnCr-LDHs shows low removal efficiency for o-xylene photodegradation, while Au/ZnCr-LDHs exhibits both excellent photodegradation rate and high TOF values for o-xylene as well as other VOCs including benzene, o-xylene, m-xylene and p-xylene. The kinetic equation and activation energy were calculated for o-xylene photodegradation, which are [Formula: see text] and 21.

Orthogonal synthesis of a novel hybrid layered material containing three different zincous components and its photocatalytic property investigation.

A novel hybrid layered material-Schiff Base-Zinc Complexes intercalated ZnCr-LDHs-supported ZnO-was synthesized by one-step coprecipitation method and characterized by XRD, UV-vis DRS, SEM, TEM, BET, ICP-AES and XPS analysis. The influences of the three Zn components (intercalated between the layers, supported on the surface, distributed in the host layers of the layered material) on the crystallinity and the photocatalytic activity of ZnO/ZnCr-SalenZn-LDHs for Rhodamine B (RhB) degradation were studied in detail by orthogonal design. The results showed that the percentage of the three components has a great effect on the structure and photocatalytic performance of ZnO/ZnCr-SalenZn-LDHs.

Ti/ZnO-MxOy composites (M = Al, Cr, Fe, Ce): synthesis, characterization and application as highly efficient photocatalysts for hexachlorobenzene degradation.

A series of novel organic-inorganic nanoscale layered materials were synthesized by intercalating the Ti-containing Schiff base complex into the interlayer of the ZnM layered double hydroxides (LDHs, M = Al, Cr, Fe, Ce). The hybrid material was further calcined to make metal oxide composites with highly dispersed Ti elements (Ti/ZnO-MxOy). The structural characterization and photocatalytic results showed that, after intercalation and calcination, the metal oxide composites with a unique flower-like crystal morphology not only had high specific surface area, uniform pore size distribution and narrow band gap, but also showed extremely high photocatalytic performance for hexachlorobenzene (HCB) degradation.

Photocatalytic degradation of methylene blue with a nanocomposite system: synthesis, photocatalysis and degradation pathways.

Three different composites, including a calcined FeOOH supported ZnAl layered double hydroxide (FeOOH-LDO), a calcined ZnAl layered double hydroxide (ZnAl-LDO) and a calcined ZnFeAl layered double hydroxide (ZnFeAl-LDO), were synthesized via a sol-gel method, and their activity for the visible light photocatalytic degradation of methylene blue (MB) was studied. The composites were characterized by PXRD, SEM, and BET techniques, confirming the formation of highly crystalline structures. The activity performance of MB degradation was in the following order: FeOOH-LDO (∼95%) > ZnFeAl-LDO (∼60%) > ZnAl-LDO (∼23%).

Layered double hydroxides as efficient photocatalysts for visible-light degradation of Rhodamine B.

A series of Zn/M-NO3-LDHs (M=Al, Fe, Ti, and Fe/Ti) have been synthesized by two different methods, and their activities for visible-light photocatalytic degradation on Rhodamine B (RB) were tested. Solids were analyzed by XRD, FT-IR, and ICP characterization, confirming the formation of pure LDH phase with good crystal structure. It was observed that the band gap of these nitrate LDH materials was following this order: Zn/Fe-NO3-LDHs (2.

Direct determination of impurities in high purity silicon carbide by inductively coupled plasma optical emission spectrometry using slurry nebulization technique.

A novel method for the determination of Al, Ca, Cr, Cu, Fe, Mg, Mn, Ni and Ti in high purity silicon carbide (SiC) using slurry introduction axial viewed inductively coupled plasma optical emission spectrometry (ICP-OES) was described. The various sizes of SiC slurry were dispersed by adding dispersant polyethylene imine (PEI). The stability of slurry was characterized by zeta potential measurement, SEM observation and signal stability testing.

Treatment of methyl orange by calcined layered double hydroxides in aqueous solution: adsorption property and kinetic studies.

Adsorption of a weak acid dye, methyl orange (MO) by calcined layered double hydroxides (LDO) with Zn/Al molar ratio of 3:1 was investigated. In the light of so called "memory effect," LDO was found to recover their original layered structure in the presence of appropriate anions, after adsorption part of MO(-) and CO(2-)(3) (come from air) intercalated into the interlayer of LDH which had been supported by XRD and ICP. The results of adsorption experiments indicate that the maximum capacity of MO at equilibrium (Q(e)) and percentage of adsorption (eta%) with a fixed adsorbent dose of 0.

Selective quantification of trace palladium in road dusts and roadside soils by displacement solid-phase extraction online coupled with electrothermal atomic absorption spectrometry.

There is a growing concern about the effect of palladium on human health because of the toxicity and increasing occurrence of palladium as a result of its extensive use in automotive catalytic converters. Development of reliable analytical methodologies for the determination of palladium in environmental materials is of great importance for critical evaluation of the possible risks for human health. In this work, a displacement solid-phase extraction technique was developed and online coupled to electrothermal atomic absorption spectrometry (ETAAS) for selective and sensitive determination of trace palladium in environmental samples without need of any special selective complexing agents, selective sorbents, and masking agents.

Determination of trace mercury in environmental and foods samples by online coupling of flow injection displacement sorption preconcentration to electrothermal atomic absorption spectrometry.

The toxic effects of mercury are well-known. To establish sources of mercury contamination and to evaluate levels of mercury pollution, sensitive, selective, and accurate analytical methods with excellent reproducibility are required. We have developed a novel methodology for the determination of trace mercury in environmental and foods samples by online coupling of flow injection (FI) displacement sorption preconcentration in a knotted reactor (KR) to electrothermal atomic absorption spectrometry (ETAAS).