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Plasma treatment as an effective strategy can simultaneously achieve surface modification and heteroatom doping. Here, an N/P-doped NiFeV oxide nanosheet catalyst (N/P-NiFeVO) constructed by Ar/PH3 plasma treatment is used to drive the oxygen evolution reaction (OER). The introduction of V species leads to the formation of an ultrathin ordered nanostructure and exposure of more active sites. Compared to the 2D NiFeV LDH, the prepared N/P-NiFeVO by plasma treatment possesses multiple-valence Fe, V and Ni species, which regulate the intrinsic electronic structure and enable a superior catalytic activity for the OER in alkaline media. Specifically, the N/P-NiFeVO only require an overpotential of 273 mV to drive the current density of 100 mA cm−2. What's more, the electrode can maintain a stable current density in a long-term oxygen evolution reaction (∼120 h) under alkaline conditions. This work provides new insight for the rational design of mixed metal oxides for OER electrocatalysts. [ABSTRACT FROM AUTHOR]

H3PW12O40-modified MnOx catalysts (denoted as Mn-HPW) were used for NOx elimination with co-fed NH3. The optimal Mn-HPW0.02 catalyst exhibited over 90% NOx conversion at 90–270 °C. The incorporation of HPW increased the amount of Lewis acid sites of the catalyst for adsorbing NH3, and accelerated the reaction between the adsorbed NH3 species and gas-phase NOx, thus, increasing the low-temperature catalytic activity. The oxidation ability of the Mn catalyst was decreased due to the addition of HPW, thus, mitigating the overoxidation of the adsorbed NH3 species and improving the de-NOx activity and N2 selectivity in the high-temperature region. DRIFT results revealed that the NH3 species on Lewis and Brønsted acid sites, bridged nitrate, and bidentate nitrate were important species/intermediates for the reaction. NH3-SCR over the Mn and Mn-HPW0.02 catalysts obeyed the Eley–Rideal and Langmuir–Hinshelwood mechanisms, simultaneously, at 120 °C. [ABSTRACT FROM AUTHOR]

A series of Ce1−xFexVO4 (x = 0, 0.25, 0.50, 0.75, 1) catalysts prepared by modified hydrothermal synthesis were used for selective catalytic reduction (SCR) of NOx with NH3. Among them, Ce0.5Fe0.5VO4 showed the highest catalytic activity. The catalysts were characterized by X-ray diffraction (XRD), N2 adsorption–desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray fluorescence (XRF), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction using H2 (H2-TPR), and temperature-programmed desorption of NH3 (NH3-TPD). The results indicated the formation of Ce-Fe-V-O solid solutions. The average oxidation states (AOS) of Ce, Fe, V, and O atoms changed obviously with the incorporation of Fe3+ into CeVO4, and the acidity of Ce0.5Fe0.5VO4 differs from that of CeVO4 and FeVO4. The presence of more acid sites and a sharp increase in active oxygen species in Ce0.5Fe0.5VO4 effectively improved the selective catalytic reduction (SCR) activity. [ABSTRACT FROM AUTHOR]

[Display omitted] Efficient and durable electrocatalysts with sufficient active sites and high intrinsic activity are essential for advancing energy-saving hydrogen production technology. In this study, a Mott-Schottky heterojunction electrocatalyst with Ag nanoparticles in-situ grown on NiFe layered double hydroxides (NiFe-LDH)/NiFe 2 O 4 nanosheets (Ag@NiFe-LDH/NiFe 2 O 4) were designed and successfully synthesized through a hydrothermal process and subsequent spontaneous redox reaction. The in-situ growth of metallic Ag on semiconducting NiFe-LDH/NiFe 2 O 4 triggers a strong electron interaction across the Mott-Schottky interface, leading to a significant increase in both the intrinsic catalytic activity and the electrochemical active surface area of the heterojunction electrocatalyst. As a result, the Ag@NiFe-LDH/NiFe 2 O 4 demonstrates impressive oxygen evolution reaction (OER) performance in alkaline KOH solution, achieving a low overpotential of 249 mV at 100 mA cm−2 and a Tafel slope of 42.79 mV dec−1. When the self-supported Ag@NiFe-LDH/NiFe 2 O 4 is coupled with the Pt/C electrocatalyst, the alkaline electrolyzer reaches a current density of 10 mA cm−2 at a cell voltage of only 1.460 V. Furthermore, X-ray photoelectron spectroscopy and in-situ Raman analysis reveal that the Ni(Fe)OOH is the possible active phase for OER in the catalyst. In addition, when employed for UOR catalysis, the Ag@NiFe-LDH/NiFe 2 O 4 also displays intriguing activity with an ultralow potential of 1.389 V at 50 mA cm−2. This work may shed light on the rational design of multiple-phase heterogeneous electrocatalysts and demonstrate the significance of interface engineering in enhancing catalytic performance. [ABSTRACT FROM AUTHOR]

• MCF silica supported CuO CeO 2 catalysts were used for CO oxidation. • CD-assisted co-impregnation was superior to traditional co-impregnation. • Catalyst prepared by CD-assisted method has high activity and stability. • Kind of CD used in preparation has no distinct effect on catalyst activity. • Amount of CD used in preparation has no distinct effect on catalyst activity. A CuO-CeO 2 /MCF catalyst was prepared by cyclodextrin-assisted co-impregnation (CC/M-CD). For comparison, a reference catalyst was prepared by traditional wet impregnation (CC/M). The catalysts were characterized by ICP-OES, XRD, Raman, N 2 -physisorption, TEM, EDS mapping, XPS, in situ DRIFTS, H 2 -TPR, and CO-TPD. The results show that Cu and Ce species of the CC/M-CD catalyst disperse more homogeneously, and the CC/M-CD catalyst has a larger surface area, more amounts of Cu+ and Ce3+ species, enhanced interaction between CuO and CeO 2 , and thus exhibits higher catalytic activity in CO oxidation. Additionally, the kind and amount of cyclodextrin used in the impregnating solutions have no distinct effect on the activity of CC/M-CD prepared by the cyclodextrin-assisted co-impregnation. [ABSTRACT FROM AUTHOR]

Single-ion copper doping significantly improves the catalytic activity of α-MnO2 in CO oxidation, reducing the apparent activation energy to ∼0.3 eV via strong electronic interactions between the frontier orbitals of copper ions and manganese ions. [ABSTRACT FROM AUTHOR]

Ag-Ag 3 VO 4 /AgIO 3 composites composed of Ag-Ag 3 VO 4 particles (major component) and AgIO 3 nanosheets (minor component) were obtained via photoreduction of Ag 3 VO 4 /AgIO 3 composites prepared by sequential precipitation. The optimal Ag-Ag 3 VO 4 /AgIO 3 catalysts (in particular, the one with an AgIO 3 /Ag 3 VO 4 mass ratio of 6.4%) were found to be more active than AgIO 3 , Ag 3 VO 4 , and Ag-Ag 3 VO 4 in the photocatalytic degradation of rhodamine B (RhB), methylene blue (MB), methyl orange (MO), and tetracycline hydrochloride (TC) under visible-light irradiation. Ag-Ag 3 VO 4 /AgIO 3 can be reused in cycling experiments. Photogenerated holes (h + ) and superoxide radical anions ( O 2 − ) were demonstrated by radical-capture experiments as the main active species in the photocatalytic degradation of RhB. The more efficient separation and transfer of photogenerated electron-hole pairs are responsible for the enhanced activity of Ag-Ag 3 VO 4 /AgIO 3 . A possible photocatalytic mechanism is proposed. [ABSTRACT FROM AUTHOR]

A novel Ag 3 VO 4 /BiOIO 3 heterojunction catalyst was prepared by loading Ag 3 VO 4 nanoparticles onto BiOIO 3 nanosheets via precipitation. Ag 3 VO 4 /BiOIO 3 exhibited obviously higher activity than Ag 3 VO 4 and BiOIO 3 in photocatalytic degradation of aqueous dyes and tetracycline hydrochloride under visible-light irradiation. The recyclability of the catalyst was confirmed by cycling experiments. Photogenerated holes (h + ) and superoxide radical anions ( · O 2 − ) were demonstrated to be the main active species. Ag 3 VO 4 /BiOIO 3 can facilitate the separation and transfer of photogenerated carriers more efficiently than Ag 3 VO 4 and BiOIO 3 . Possible photocatalytic mechanisms were proposed. [ABSTRACT FROM AUTHOR]

Visible-light-driven photocatalysis for removing industrial dyes and antibiotics in waste water has attracted much interest. New catalysts with enhanced photocatalytic performance have been actively sought. Herein, via a simple sequential precipitation method, AgI nanoparticles were anchored onto micron-sized β-Ag 2 MoO 4 particles to form AgI/β-Ag 2 MoO 4 p–n heterojunctions. These heterojunctions exhibited remarkably upgraded activities in the visible-light-driven photocatalytic degradation of rhodamine B, methyl orange, and tetracycline hydrochloride compared with pristine AgI and β-Ag 2 MoO 4 . The enhanced photocatalytic activity can be mainly attributed to the tight heterojunction structure and well matched energy band that may facilitate the separation and transfer of photogenerated electron–hole pairs. Photogenerated holes (h + ) and superoxide radical anions (•O 2 − ) were found to be the main active species. A possible photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag 3 VO 4 /BiOBr n-p heterojunctions were prepared via chemical deposition. • Ag 3 VO 4 /BiOBr consists of Ag 3 VO 4 nanoparticles and BiOBr microspheres. • Highly efficient for degradation of organic dyes under visible light. • The optimal BiOBr/Ag 3 VO 4 mass ratio is ∼10%. • Superoxide radical anions and photogenerated holes are primary active species. Ag 3 VO 4 /BiOBr n-p heterojunctions were prepared via chemical deposition. Ag 3 VO 4 /BiOBr consists of Ag 3 VO 4 nanoparticles with sizes ranging from several to tens nanometers and flower-like BiOBr microspheres composed of irregular nanosheets. The photocatalytic performance of Ag 3 VO 4 /BiOBr and relevant samples was investigated in the visible-light-driven degradation of Rhodamine B (RhB), methylene blue (MB), methyl orange (MO), and tetracycline hydrochloride (TC). Ag 3 VO 4 /BiOBr heterojunction with a BiOBr/Ag 3 VO 4 mass ratio of 10% was more active than a physical mixture of Ag 3 VO 4 and BiOBr, showing the importance of forming the heterojunction. Photogenerated holes (h+) and superoxide radical anions (O 2 −) were found to be the primary active species. A possible mechanism for the enhanced photocatalytic performance was proposed. [ABSTRACT FROM AUTHOR]

A series of Mo–Co–K sulfide catalysts were prepared by co-precipitation, and their catalytic performance in CO 2 hydrogenation to C 2+ alcohols and other products was studied. The catalysts with K/Mo molar ratio of 0.3–1.2 and Co/Mo molar ratio of 1.0 showed relatively high CO 2 conversions and high selectivities to total alcohols and C 2+ alcohols. Under optimal reaction conditions (320 °C, 12.0 MPa, and 3000 ml/(g h)), the CO 2 total conversion and CO 2 conversion free of CO reached 28.8% and 12.6%, respectively, over Mo 1 Co 1 K 0.8 sulfide, and the corresponding selectivities to alcohols and C 2+ alcohols (free of CO) are 81.8% and 10.9%, respectively. The catalytic performance can be modified by the addition of SiO 2 , Al 2 O 3 , TiO 2 , or activated carbon to Mo 1 Co 1 K 0.6 sulfide during the synthesis. The physicochemical properties of the modified catalysts were characterized by XRD, N 2 adsorption–desorption, SEM, XPS, CO 2 -TPD, and H 2 -TPD. In particular, the activated carbon-modified catalyst has a stronger interaction between Mo and Co, more Mo 4+ content on catalyst surface, and appropriate ability for adsorbing CO 2 and H 2 , which may be beneficial for achieving high selectivity to C 2+ alcohols. [ABSTRACT FROM AUTHOR]

LaPO 4 has been used as a support to make supported catalysts in some investigations, but the effect of different LaPO 4 supports on the catalytic performance of supported catalysts has been rarely reported. In this work, conventional hexagonal LaPO 4 (LaPO 4 H) was prepared by precipitation, and hexagonal LaPO 4 nanowires (LaPO 4 HNW) was prepared by hydrothermal synthesis at 150 °C. Monoclinic LaPO 4 nanowires (LaPO 4 -MNW-220 and LaPO 4 -MNW-900) were prepared by hydrothermal synthesis at 220 °C or calcining LaPO 4 HNW at 900 °C. These samples were used to support Rh 2 O 3 via impregnation using Rh(NO 3 ) 3 as a precursor. The activities of these supported catalysts in N 2 O decomposition and CO oxidation follow the same sequence of Rh 2 O 3 / LaPO 4 HNW > Rh 2 O 3 / LaPO 4 H > Rh 2 O 3 / LaPO 4 -MNW-220 > Rh 2 O 3 / LaPO 4 -MNW-900, i.e. , two hexagonal LaPO 4 supports are better than two monoclinic LaPO 4 supports in making active catalysts, and hexagonal LaPO 4 nanowires are better than hexagonal LaPO 4 composed of nanoparticles and short nanorods. The most active catalyst has highly dispersed Rh 2 O 3 species interacting strongly with the support, more oxygen-adsorption capacity, and more basic sites. [ABSTRACT FROM AUTHOR]

RuO x /M–P–O (M = Mg, Al, Ca, Fe, Co, Zn, La) catalysts were prepared by impregnating commercial metal phosphates with RuCl 3 , followed by calcination in air at 500 °C. The catalytic performance in N 2 O decomposition was studied. Among these catalysts, RuO x /Ca–P–O (also denoted as RuO x /HAP, HAP = hydroxyapatite) showed the highest activity, achieving complete N 2 O conversion at 400 °C. RuO x /Mg–P–O was the second most active, showing 46.3% N 2 O conversion at 400 °C. The presence of 5.0 vol.% O 2 or 2.0 vol.% H 2 O in the reaction mixture inhibited the catalytic activity of RuO x /HAP to some extent, but the inhibiting effect was reversible, i.e. , the activity was restored after O 2 or H 2 O was retracted. The influences of pretreatment by H 2 as well as different Ru-containing precursors on the catalytic performance of RuO x /HAP were also studied. The characterization data indicate that RuO x /HAP has a not-so-small surface area (49.5 m 2 /g), highly dispersed amorphous RuO x species, as well as relatively abundant basic sites, O 2 -adsorption sites, and surface hydroxyls. [ABSTRACT FROM AUTHOR]

Recently, we reported the hydrothermal conversion of Fe 2 O 3 /SiO 2 spheres (Fe 2 O 3 nanoparticles supported on SiO 2 spheres) into Fe 2 O 3 /Fe-Silicalite-1 nanowires in the presence of ethylenediamine and triethylamine (Micropor. Mesopor. Mater. 200 (2014) 52–60). The catalytic performance of Fe 2 O 3 /Fe-Silicalite-1 nanowires in CO oxidation, N 2 O decomposition, and catalytic reduction of NO by NH 3 was evaluated. However, the nature of active Fe species of Fe 2 O 3 /Fe-Silicalite-1 nanowires in N 2 O decomposition was not clear. In the current work, additional samples (i.e., Fe-Silicalite-1, Fe 2 O 3 /Silicalite-1, and Fe 2 O 3 /Fe-Silicalite-1) were prepared by using conventional Silicalite-1 as a precursor, and tested in N 2 O decomposition. Fe 2 O 3 /Silicalite-1 and Fe 2 O 3 /Fe-Silicalite-1 prepared by impregnation showed higher activities than Fe-Silicalite-1 prepared by isomorphous substitution, and Fe 2 O 3 /Fe-Silicalite-1 nanowires showed the highest activity among these samples. Through relevant characterization employing XRD, XRF, N 2 adsorption, TEM, UV–vis, and 57 Fe Mössbauer spectroscopy, we conclude that small Fe 2 O 3 nanoparticles with size of 1–2 nm are the main active Fe species for N 2 O decomposition, whereas framework Fe 3+ and larger Fe 2 O 3 particles are not so active. [ABSTRACT FROM AUTHOR]

The new uranyl, nickel and cobalt complexes, [UO 2 (L 1 ) 2 (R)] ( 1 ), [Ni(L 1 ) 2 ((CH 3 ) 2 S O) 2 ] ( 2 ), [Co(H 2 O) 4 (HL 2 ) 2 ]·2H 2 O ( 3 ) and [UO 2 (H 2 O) 2 (HL 2 ) 2 ]·2H 2 O ( 4 ), were prepared by reaction of UO 2 (CH 3 COO) 2 ·2H 2 O, Ni(CH 3 COO) 2 ·4H 2 O or Co(CH 3 COO) 2 ·4H 2 O with 1,3-diphenyl-propane-1,3-dione (H 2 L 1 ) or 4-(2-(2,4-dioxopentan-3-ylidene)hydrazinyl)benzoic acid (H 2 L 2 ) in the presence of N,N-diethylnicotinamide (R) (for 1 ). Complexes 1 – 4 were characterized by elemental analysis, IR spectroscopy, ESI-MS and single crystal X-ray diffraction technique. In both 1 and 2 the (L 1 ) − coordinates in a bidentate chelating mode where the UO 2 2+ in 1 exhibits a distorted pentagonal bipyramidal and Ni 2+ in 2 a distorted octahedral geometries. In 3 and 4 a hydrazone moiety containing an intramolecular resonance assisted hydrogen bond, with N–H⋯O distances of 2.5469(18) and 2.549(7) Å, respectively, was found in the coordinated ligand (HL 2 ) − . The supramolecular networks (packing diagrams) of 1 – 4 are constructed via hydrogen bonding, CH–π or π–π interactions. All the four complexes ( 1 – 4 ) act as a good catalyst towards the diastereoselective nitroaldol (Henry) reaction of aliphatic and aromatic aldehydes with nitroethane in different solvents such as acetonitrile, methanol or water. Complex 3 was found to be efficient catalyst for the Henry reaction in aqueous medium, providing β-nitroalcohols with good yields (68–91%) and diastereoselectivities ( syn / anti 77:23–73:27). [ABSTRACT FROM AUTHOR]

Sub-10 nm CeO particles were highly dispersed on Hollandite-type manganese oxide (HMO) to give a CeO/HMO catalyst, which showed obviously higher activity than HMO and CeO alone in CO oxidation and selective catalytic reduction of NO by NH. A combination of various characterization data with the catalytic tests revealed that the enhanced catalytic activity results from the strong interaction between CeO and HMO to activate the transfer of electron, the improved redox ability of surface oxygen due to an increased electron density, and the presence of more surface active oxygen species. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Highlights: [•] La2O3-modified Ni/SBA-15 catalysts were studied in CH4 reforming with CO2. [•] Ni dispersion and the catalytic performance were improved with La addition. [•] The promoting intermediates were trapped in a designed infrared cell. [•] La promotes the reforming mainly by adsorbing CO2 and facilitating CO* and CH x O*. [ABSTRACT FROM AUTHOR]

Ni-modified Ag/SiO2 catalysts containing 0~3 wt.% Ni were obtained by impregnating Ni species onto Ag/SiO2 followed by calcination and reduction. The catalysts' performance in the hydrogenation of dimethyl oxalate (DMO) to methyl glycolate (MG) was tested. Ag-0.5%Ni/SiO2 showed the highest catalytic activity among these catalysts and exhibited excellent catalytic stability. The effects of the Ni content on the structure and surface chemical states of catalysts were investigated by XRF, N2-sorption, XRD, TEM, EDX-mapping, FT-IR, H2-TPR, UV–vis, and XPS. The better catalytic activity and stability of Ni-modified Ag/SiO2 (versus Ag/SiO2) are ascribed to the improved dispersion of active Ag species as well as the higher resistance to the growth of Ag particles due to the presence of Ni species. [ABSTRACT FROM AUTHOR]

Three known multinuclear Zn(II)-arylhydrazone complexes, [Zn{(CH 3) 2 SO}(H 2 O)(L1)] (1), [Zn 2 (CH 3 OH) 2 (μ -L2) 2 ] (2) and [Zn 4 (μ -OH) 2 (1κ O :2κ O -HL3) 4 (κ O -HL3) 2 (H 2 O) 4 ] (3) were prepared upon reaction of ZnCl 2 or Zn(CH 3 COO) 2 ·2H 2 O with 3-(2-(2-hydroxy-4-nitrophenyl) hydrazineylidene) pentane-2,4-dione (H 2 L1), 3-(2-(2-hydroxyphenyl)hydrazineylidene)pentane-2,4-dione (H 2 L2) and 2-(2-(2,4-dioxopentan-3-ylidene)hydrazineyl)benzoic acid (H 2 L3), respectively, in methanol solution. Compounds 1 – 3 were tested as catalysts for the cyanosilylation reaction of a diversity of both aliphatic and aromatic aldehydes with trimethylsilyl cyanide yielding the corresponding cyanohydrin trimethylsilyl ethers in high yields (72–98%) in methanol and at room temperature. Image 1 • Multinuclear zinc(II) complexes with arylhydrazones of active methylene compounds. • A tetranuclear zinc(II) complex shows high catalytic activity in cyanosilylation of aldehydes. • The yield of cyanohydrin trimethylsilyl ethers depends on the amounts of catalyst and nature of solvents. [ABSTRACT FROM AUTHOR]

The unique core–shell electrocatalyst with heterostructured Ni 4 Mo/MoO 2 shell and defect-rich NiMoO 4 core was designed as an efficient bifunctional electrocatalyst for overall water splitting. [Display omitted] • Rational design of core–shell structured electrocatalysts was achieved by making full use of various active sites. • Synergistic effect of the hetero-interface and defect engineering endows the electrocatalyst with excellent bifunctional catalytic activity for HER and OER. • DFT calculations reveal that the construction of the Ni 4 Mo/MoO 2 heterostructure effectively accelerates H 2 O dissociation kinetics. Despite great efforts over the past decade, rational design of bifunctional electrocatalysts with low cost and high efficiency still remains a challenge to achieve industrial water splitting. Herein, we synthesized the nickel-molybdenum nanorod array catalyst supported on NF (NMO@NM/MO) by a two-step process of hydrothermal and reductive annealing. Partial reduction of the NiMoO 4 induces the structural reconstruction and formation of the Ni 4 Mo/MoO 2 heterostructure on oxygen vacancy enriched nanorod, which bring out sufficient active sites, large specific surface area and favorable interfacial charge transfer. Thanks to the unique core–shell structure with the heterostructured Ni 4 Mo/MoO 2 surface and defect-rich NiMoO 4 core, the obtained electrocatalyst shows greatly improved hydrogen evolution reaction (HER) activity with an ultralow overpotential of 63 mV at 100 mA cm−2 (vs. 314 mV for the NiMoO 4). Density function theory calculations reveal that the construction of the Ni 4 Mo/MoO 2 heterostructure effectively accelerates H 2 O dissociation kinetics, while the defective NiMoO 4 facilitates H* adsorption/desorption. Moreover, the heterostructure catalyst also displays excellent oxygen evolution reaction (OER) performance with the low overpotential of 274 mV at 100 mA cm−2. When coupling HER and OER by using NMO@NM/MO as both the cathode and anode, the alkaline electrolyzer delivers a current density of 10 mA cm−2 at only 1.50 V as well as good robustness. The synergistic effect of the hetero-interface and the defect engineering endows the electrocatalyst with excellent bifunctional catalytic activity for HER and OER. This work may provide a route for rational design of heterostructure electrocatalysts with multiple active components. [ABSTRACT FROM AUTHOR]

Ag 2 O/Bi 2 MoO 6 composed of flower-like Bi 2 MoO 6 microspheres (diameter: 1–3 μm) and well dispersed Ag 2 O nanoparticles (size: ∼10 nm) was prepared via solvothermal deposition-precipitation. The catalytic performance of Ag 2 O/Bi 2 MoO 6 and other samples in photocatalytic degradation of Rhodamine B (RhB) and methyl orange (MO) dye under visible light irradiation (λ > 420 nm) was studied. Ag 2 O/Bi 2 MoO 6 p-n heterojunction exhibited higher activity than Bi 2 MoO 6 or Ag 2 O with the same weight of the corresponding component in Ag 2 O/Bi 2 MoO 6 . It was even more active than a mixture of Bi 2 MoO 6 and Ag 2 O. The high photocatalytic activity of Ag 2 O/Bi 2 MoO 6 was due to the efficient separation of photogenerated electron-hole pairs. The photogenerated holes (h + ) and superoxide radical anions ( O 2 − ) were found to be the primary reactive species for the degradation of RhB dye in aqueous solution. [ABSTRACT FROM AUTHOR]

A series of Fe-ZSM-11 catalysts were prepared by different methods and tested in N 2 O decomposition. First, Fe-ZSM-11 catalysts with different Si/Al ratios (15, 25, 36) were prepared by wet ion exchange. The Fe content and catalytic activity were highest for the catalyst with Si/Al ratio 15. Additional Fe-ZSM-11 catalysts with higher Fe contents were prepared by semicontinuous ion exchange or by using alkaline-treated ZSM-11 as the precursor for wet ion exchange. While the catalyst prepared by semicontinuous ion exchange showed low activity, the catalyst prepared using alkaline-treated ZSM-11 turned out to be the most active in this study. Relevant characterization was conducted using X-ray diffraction, X-ray fluorescence, inductively coupled plasma, N 2 adsorption–desorption, scanning electron microscopy, transmission electron microscopy, ultraviolet–visible spectroscopy, 57 Fe Mössbauer spectroscopy, magnetization tests, and X-ray photoelectron spectroscopy. Our data indicate that small FeO x nanoparticles and large iron oxide particles are the predominant Fe species, and small FeO x nanoparticles with low nuclearity are the active Fe species. [ABSTRACT FROM AUTHOR]

CeVO 4 -based photocatalysts have been actively studied, but to the best of our knowledge, P-doped CeVO 4 with enhanced photocatalytic activity has not been reported. Herein, novel P-doped CeVO 4 nanorods were synthesized via a facile hydrothermal method. The doped P exists as PO 4 tetrahedron which replaces VO 4 tetrahedron. The crystal size, specific surface area, and light absorption ability of CeVO 4 were tuned after doping CeVO 4 by P. In particular, the separation and transmission efficiency of photogenerated electron-hole pairs were improved due to the internal electric field caused by the large charge density around PO 4 tetrahedron. This conclusion was also confirmed by DFT calculations. The photocatalytic activities of different samples were tested via photodegradation of aqueous organic pollutants, and a feasible mechanism of photocatalytic reaction was proposed. [ABSTRACT FROM AUTHOR]

• Activation temperature exerts important effect on CuO-CeO 2 catalyst. • The catalyst activated at 550 °C exhibits superior activity and moisture resistance. • Activity is closely related to contents of Cu+ species and oxygen vacancies. • Dispersed CuO with strong interaction with CeO 2 exhibits good moisture resistance. • Bulk CuO with no or weak interaction with CeO 2 exhibits poor moisture resistance. Development of a highly efficient Cu-based catalyst for low-temperature CO oxidation under moisture condition remains a grand challenge. In this paper, effect of activation temperature (350–800 °C) on catalytic performance of CuO-CeO 2 , prepared by facile one-step solvothermal synthesis, in CO oxidation was investigated, and the catalysts' physicochemical properties were studied by TG-DSC, ICP-AES, N 2 sorption, XRD, TEM, Raman spectroscopy, XPS, in-situ DRIFTS, H 2 -TPR, CO-TPD, and O 2 -TPD. It was found that activation at 550 °C is beneficial for the interaction between CuO and CeO 2 , leading to the formation of more Cu+ species and oxygen vacancies advantageous for improving the catalytic activity. Activation at 800 °C, nevertheless, would weaken the interaction between CuO and CeO 2 due to the sintering of CuO and CeO 2 , thus decreasing the catalytic activity and moisture resistance. Interestingly, no deactivation was observed over the optimal catalyst (activated at 550 °C) after 50 h testing at a low temperature of 87 °C (at which 90% CO conversion was obtained), even when 4.2% water vapor was added into the feed gas. [ABSTRACT FROM AUTHOR]

Twonew ferrocenyl (Fc) group containing 1,5-diaza-3,7-diphosphacyclooctaneligands, PFc2NAr2(1, Ar = Ph; 2, Ar = p-BrC6H4), were prepared by reaction of FcPH2with 2 equiv of paraformaldehyde in glycol followed by treatmentof the resulting FcP(CH2OH)2with 1 equiv ofaniline or p-bromoaniline in 79% and 67% yields,respectively; however, ligands 1and 2couldbe also prepared by treatment of the isolated and purified FcP(CH2OH)2with 1 equiv of aniline or p-bromoaniline under similar conditions in 80% and 72% yields, respectively.Further treatment of 1or 2with the complexsalt [Ni(MeCN)6](BF4)2in MeCN atroom temperature resulted in formation of the first ferrocenyl-containingcomplexes [Ni(PFc2NAr2)2](BF4)2(3, Ar =Ph; 4, Ar = p-BrC6H4) in 95% and 90% yields, respectively. Compounds 1–4were structurally characterized by elemental analysis andspectroscopy and particularlyfor 1,2, and 4by X-ray crystallography.When the cyclic voltammetric behavior of 1–4was investigated, 3and 4werefound to be electrocatalysts for proton reduction of TFA to give hydrogenunder CV conditions. [ABSTRACT FROM AUTHOR]

An FeCeO x solid solution with an Fe/Ce molar ratio of 1 was obtained via a modified sol-gel method. The promotional effect of Fe3+ ions in the lattice of cubic CeO 2 for catalytic reduction of NO with NH 3 was studied. The NO conversion over the FeCeO x catalyst was obviously higher than those over CeO 2 and Fe 2 O 3 catalysts. FeCeO x was characterized by using XRD, TEM, and XANES, etc. The experimental results revealed that Fe substituted Ce in CeO 2 to form an Fe–O–Ce solid solution with high activity for catalytic reduction of NO. The atomic and electric structures of the FeCeO x catalyst were studied to explain the enhanced catalytic activity. • FeCeO x solid solution was obtained via a modified sol-gel method. • Catalytic reduction of NO with NH 3 can be enhanced. • FeCeO x was characterized by using XRD, TEM, and XANES, etc. • Atomic and electric structures were studied to explain the enhanced activity. [ABSTRACT FROM AUTHOR]

• Protoporphyrin was coupled with pGCN via sonication. • The modified catalyst extends the light absorption to the near-infrared region. • Highly efficient for H 2 evolution under Vis-NIR or NIR irradiation. • Reasons for the improved performance were studied systematically. Although many photocatalysts can work under ultraviolet-visible (UV–vis) light, few photocatalysts can use the near-infrared (NIR) portion of sun light. Herein, we developed a new photocatalyst (denoted as Pp/pGCN) by modifying protonated g-C 3 N 4 (pGCN) with protoporphyrin (Pp). Pp/pGCN showed superior activity than g-C 3 N 4 (GCN), pGCN, and Pp in photocatalytic water splitting to produce H 2 , either under Vis-NIR (λ > 420 nm) light or NIR (λ > 780 nm) light. Reasons for the enhanced catalytic activity were elucidated via relevant physicochemical characterization. This work may furnish a new example for the design of new photocatalysts that can make full use of the NIR portion of sunlight. [ABSTRACT FROM AUTHOR]