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Three-dimensionally ordered macroporous (3DOM) photocatalysts BiVO 4 (denoted as 3D-BiV), AgBr/3D-BiV, and 0.17 wt% M/AgBr/3D-BiV (M Au, Pt, and Pd) were prepared using the polymethyl methacrylate-templating, low-temperature deposition, and polyvinyl alcohol-protected reduction methods, respectively. The as-prepared BiVO 4 possessed a good-quality 3DOM structure and a high surface area. It is found that the AgBr and noble metals were uniformly distributed on the surface of 3D-BiV. Among the M/AgBr/3D-BiV samples, the 0.17 wt% Pd/AgBr/3D-BiV sample showed the highest photocatalytic activity for the degradation of 4-chlorophenol (4-CP) under visible light illumination (i.e., complete 4-CP degradation could be achieved within 150 min), which was associated with its good 3DOM structure, high surface oxygen adspecies concentration, easy transfer and separation of photogenerated carriers, and synergistic effect between AgBr or Pd nanoclusters and BiVO 4 . [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensionally macroporous perovskite-type oxides EuFeO3 (EFO-3DOM, EFO-sucrose-1, EFO-sucrose-2, and EFO-sucrose-3, respectively) have been prepared using the polymethyl methacrylate-templating method in the absence or presence of sucrose. Physicochemical properties of the materials were characterized by means of a number of analytical techniques, and their catalytic activities were evaluated for the total oxidation of toluene. It is shown that all of the EFO samples were of single-phase orthorhombic crystal structure with a 3DOM architecture. The sucrose addition during the preparation process had a great effect on the surface area and porous structure of the final product. A clear correlation of surface area, surface oxygen species concentration, and low-temperature reducibility with the catalytic performance was observed. The EFO-sucrose-1 catalyst performed the best, giving the T 50% and T 90% of 312 and 347 °C at space velocity = 20,000 mL/(g h), respectively. The apparent activation energies of the 3DOM-structured EFO samples were in the range of 82–97 kJ/mol. It is concluded that the higher surface area and oxygen adspecies concentration and better low-temperature reducibility account for the good catalytic activity of EFO-sucrose-1. [Copyright &y& Elsevier]

Highlights: [•] Ordered mesoporous cobalt oxide (meso-Co3O4) is obtained via KIT-6-templating route. [•] xAu/meso-Co3O4 nanocatalysts are prepared using the colloidal deposition method. [•] Au nanoparticles are highly dispersed inside the mesoporous channels of meso-Co3O4. [•] xAu/meso-Co3O4 perform well in the oxidation of CO, benzene, toluene, and o-xylene. [•] There is a strong interaction between Au nanoparticles and meso-Co3O4. [ABSTRACT FROM AUTHOR]

Highlights: [•] High-surface-area 3DOM La0.6Sr0.4MnO3 is prepared by the PMMA-templating method. [•] Surfactant addition is critical in 3DOM structure formation with nanovoid-like walls. [•] The calcination procedure is a key step in the formation of 3DOM structure. [•] 3DOM La0.6Sr0.4MnO3-DP3 performs best in the combustion of methane. [•] Surface area, Oads, and reducibility determine the activity of 3DOM La0.6Sr0.4MnO3. [Copyright &y& Elsevier]

Abstract: Three-dimensionally ordered macroporous (3DOM) monoclinic InVO4 and its supported chromia (yCrO x /3DOM InVO4, y denotes as the weight percentage of Cr2O3, y = 5, 10, 15, and 20 wt%) photocatalysts were fabricated using the ascorbic acid-assisted polymethyl methacrylate-templating and incipient wetness impregnation methods, respectively. Physicochemical properties of the materials were characterized by means of a number of analytical techniques. Photocatalytic activities of the samples were evaluated for the degradation of rhodamine B (RhB) in the presence of H2O2 under visible-light illumination. Compared to 3DOM InVO4 and 15CrO x /bulk InVO4, yCrO x /3DOM InVO4 showed much better visible-light-driven photocatalytic performance for RhB degradation, with the 15CrO x /3DOM InVO4 sample performing the best. It is concluded that the CrO x loading, higher surface area and surface oxygen vacancy density and lower bandgap energy as well as the better quality of 3DOM structure were responsible for the good photocatalytic performance of 15CrO x /3DOM InVO4 for the degradation of RhB. [Copyright &y& Elsevier]

Porous S-doped bismuth vanadate with an olive-like morphology and its supported iron oxide ( y wt.% FeO x /BiVO 4–δ S 0.08 , y = 0.06, 0.76, and 1.40) photocatalysts were fabricated using the dodecylamine-assisted alcohol-hydrothermal and incipient wetness impregnation methods, respectively. It is shown that the y wt.% FeO x /BiVO 4–δ S 0.08 photocatalysts contained a monoclinic scheetlite BiVO4 phase with a porous olive-like morphology, a surface area of 8.8–9.2 m 2 /g, and a bandgap energy of 2.38–2.42 eV. There was co-presence of surface Bi 5+ , Bi 3+ , V 5+ , V 3+ , Fe 3+ , and Fe 2+ species in y wt.% FeO x /BiVO 4–δ S 0.08 . The 1.40 wt.% FeO x /BiVO 4–δ S 0.08 sample performed the best for Methylene Blue degradation under visible-light illumination. The photocatalytic mechanism was also discussed. We believe that the sulfur and FeO x co-doping, higher oxygen adspecies concentration, and lower bandgap energy were responsible for the excellent visible-light-driven catalytic activity of 1.40 wt.% FeO x /BiVO 4–δ S 0.08 . [ABSTRACT FROM AUTHOR]

Highlights: [•] 3DOM La0.6Sr0.4MnO3 (LSMO) is prepared by polymethyl methacrylate-templating method. [•] xAu/LSMO catalysts are prepared by the polyvinyl alcohol-protected reduction method. [•] xAu/LSMO perform excellently in the oxidation of CO and toluene. [•] Activity is governed by Oads content, reducibility, and strong Au–LSMO interaction. [ABSTRACT FROM AUTHOR]

Highlights: [•] MnO x /3DOM LaMnO3 catalysts are prepared using the in situ PMMA-templating method. [•] Manganese oxide nanoparticles are highly dispersed on the surface of 3DOM LaMnO3. [•] 12wt% MnO x /3DOM LaMnO3 exhibits the highest Oads content and best reducibility. [•] 12wt% MnO x /3DOM LaMnO3 performs well in the combustion of toluene and methanol. [•] There is a strong interaction between the MnO x and 3DOM LaMnO3. [Copyright &y& Elsevier]

Highlights: [•] Chain-like macroporous LaMnO3 is prepared by the PMMA-templating method. [•] xAu/LaMnO3 is prepared by the PVA-protected reduction method. [•] xAu/LaMnO3 possess high surface area and Oads content and good reducibility. [•] xAu/LaMnO3 perform well in the oxidation of CO and toluene. [•] There is a strong interaction between Au and LaMnO3. [Copyright &y& Elsevier]

Highlights: [•] 3DOM LaCoO3 is prepared by the polymethyl methacrylate-templating method. [•] xAu/3DOM LaCoO3 are prepared by the polyvinyl alcohol-protected reduction method. [•] xAu/3DOM LaCoO3 show high surface area and Oads concentration and good reducibility. [•] xAu/3DOM LaCoO3 perform excellently in the oxidation of CO and toluene. [•] Activity is governed by Oads content, reducibility, and strong Au–LaCoO3 interaction. [Copyright &y& Elsevier]

Highlights: [•] 3DOM InVO4 with nanovoid-like walls are obtained using the PMMA-templating method. [•] 3DOM InVO4 possesses a surface area of 35–52m2/g. [•] 3DOM InVO4 possesses a lower bandgap energy and a higher oxygen vacancy density. [•] 3DOM InVO4 performs excellently for methylene blue photodegradation. [ABSTRACT FROM AUTHOR]

Abstract: Cylinder- and cake-like Cr2O3 with a rhombohedral structure were fabricated using the hydrothermal and microemulsion methods, respectively. It is found that surface areas, surface Cr6+ and oxygen adspecies concentrations, and low-temperature reducibility of cake-like Cr2O3 were much higher or better than those of the bulk counterpart. The cake-like Cr2O3 sample showed the best catalytic performance for toluene combustion, giving the T 50% and T 90% of 229 and 240°C at SV=20,000mL/(gh), respectively. The excellent catalytic performance of cake-like Cr2O3 was associated with its oxygen adspecies concentration and good low-temperature reducibility. [Copyright &y& Elsevier]

Highlights: [•] xCo3O4/3DOM La0.6Sr0.4CoO3 (LSCO) are prepared using in situ PMMA-templating method. [•] Cobalt oxide nanoparticles are highly dispersed on the surface of 3DOM LSCO. [•] 8Co3O4/3DOM LSCO exhibits high Oads concentration and good reducibility. [•] xCo3O4/3DOM LSCO catalysts perform well in the combustion of toluene. [•] There is a strong interaction between Co3O4 and 3DOM LSCO. [ABSTRACT FROM AUTHOR]

Abstract: Porous S-doped bismuth vanadate with an olive-like morphology and its supported cobalt oxide (y wt% CoO x /BiVO4−δ S0.08, y = 0.1, 0.8, and 1.6) photocatalysts were fabricated using the dodecylamine-assisted alcohol-hydrothermal and incipient wetness impregnation methods, respectively. It is shown that the y wt% CoO x /BiVO4−δ S0.08 photocatalysts were single-phase with a monoclinic scheetlite structure, a porous olive-like morphology, a surface area of 8.8–9.2 m2/g, and a bandgap energy of 2.38–2.41 eV. There was the co-presence of surface Bi5+, Bi3+, V5+, V3+, Co3+, and Co2+ species in y wt% CoO x /BiVO4−δ S0.08. The 0.8 wt% CoO x /BiVO4−δ S0.08 sample performed the best for methylene blue degradation under visible-light illumination. The photocatalytic mechanism was also discussed. We believe that the sulfur and CoO x co-doping, higher oxygen adspecies concentration, and lower bandgap energy were responsible for the excellent visible-light-driven catalytic activity of 0.8 wt% CoO x /BiVO4−δ S0.08. [Copyright &y& Elsevier]

Abstract: Strontium ferrite (SFO) hollow spheres with or without porous shells were fabricated via a novel one-pot hydrothermal route with the assistance of glucose and/or ethylenediamine. Physicochemical properties of the materials were characterized by means of a number of analytical techniques, and their catalytic performance was evaluated for the combustion of toluene. It is shown that the SFO samples possessed an orthorhombic structure and displayed a porous hollow spherical morphology with a surface area of 18–27m2/g. The SFO sample (SFO-3) derived hydrothermally at 170°C with a glucose/ethylenediamine volumetric ratio of 0.3/1.0 exhibited the highest surface area and oxygen adspecies concentration and the best low-temperature reducibility. Among the SFO samples, the SFO-3 sample showed the best catalytic activity for toluene combustion, and the T 10%, T 50%, and T 90% were ca. 145, 255, and 298°C at a space velocity of 20,000mL/(gh), respectively. It is concluded that the good catalytic performance of SFO-3 was associated with its surface oxygen species concentration and better low-temperature reducibility. [Copyright &y& Elsevier]

Abstract: Cubically crystallized mesoporous nickel oxide nanorods and nanocubes were fabricated by using a facile microemulsion strategy with cetyltrimethylammonium bromide (CTAB) or sodium dodecyl sulfate (SDS) as surfactant. Physicochemical properties of the materials were characterized by means of a number of analytical techniques, and their catalytic activities were evaluated for the combustion of toluene. It was shown that the morphology of the samples strongly depended on the nature of surfactant: when CTAB was used, the product was mesoporous NiO nanorods; when SDS was adopted, mesoporous NiO nanocubes were obtained. The NiO-CTAB-2 sample derived with a Ni2+/CTAB molar ratio of 0.364 displayed the highest surface area (ca. 46m2/g) and the best low-temperature reducibility. A clear correlation of oxygen adspecies concentration or low-temperature reducibility with catalytic performance was observed. The high catalytic activity (T 50% =256°C and T 90% =278°C at SV=20,000mL/(gh)) for toluene combustion of NiO-CTAB-2 was related to its larger surface area, higher oxygen adspecies concentration, and better low-temperature reducibility. [Copyright &y& Elsevier]

Abstract: Porous LaFeO3 (LFO) samples with surface areas of 15–26m2/g and orthorhombic structures were prepared via a glucose-assisted hydrothermal route. Physicochemical properties of the materials were characterized by means of a number of techniques, and their catalytic activities were evaluated for toluene combustion. It is found that the sample (LFO-170) derived at a hydrothermal temperature of 170°C possessed the highest surface area and surface oxygen concentration and the best low-temperature reducibility. Among the LFO samples, the LFO-170 sample showed the best performance for toluene combustion, giving the T 10%, T 50%, and T 90% of 180, 250, and 270°C at space velocity=20,000mL/(gh), respectively. The apparent activation energies of the LFO samples were 50–55kJ/mol. We believe that the high surface area and surface oxygen concentration and good low-temperature reducibility were responsible for the good catalytic performance of the LFO-170 sample. [Copyright &y& Elsevier]

Abstract: Fluoride-doped BiVO4 with the F/Bi molar ratios of 0, 0.09, 0.13, and 0.29 (denoted as BiVO4–F0, BiVO4–F0.09, BiVO4–F0.13, and BiVO4–F0.29, respectively) were synthesized using the hydrothermal strategy with the hydrothermally derived BiVO4 as the precursor and NH4F as the fluoride source. Physicochemical properties of the materials were characterized by means of a number of analytical techniques. Photocatalytic activities of the fluoride-doped BiVO4 samples were evaluated for the degradation of phenol under visible-light irradiation. It is shown that compared to the undoped BiVO4–F0 sample, the fluoride-doped BiVO4 samples retained the monoclinic structure, but possessed higher surface areas and oxygen adspecies concentration, better light-absorbing performance, and lower bandgap energies. Among the four samples, the porous spherical BiVO4–F0.29 sample exhibited the best photocatalytic activity for the degradation of phenol in the presence of a small amount of H2O2 under visible-light illumination. It is concluded that the higher surface area and oxygen adspecies concentration, stronger optical absorbance performance, and lower bandgap energy were responsible for the excellent photocatalytic performance of BiVO4–F0.29 for the photocatalytic degradation of phenol. [Copyright &y& Elsevier]

Abstract: Three-dimensional (3D) macroporous perovskite-type oxides SrFeO3−δ (i.e., SFO-xEG, x =1, 3, and 6) with a cubic perovskite structure have been prepared using the citric acid-assisted poly(methyl methacrylate)-templating method in the presence of a certain amount (1, 3 or 6mL) of ethylene glycol (EG). The physicochemical properties of the materials were characterized by means of numerous techniques and their catalytic activities were evaluated for toluene combustion. It is shown that the SFO-3EG sample possessed the best pore quality and highest surface area (ca. 34m2/g). Most of the pores of SFO-xEG (x =1, 3, and 6) were ca. 72, 52, and 64nm, respectively. There was a good relationship of surface area, oxygen adspecies concentration, and low-temperature reducibility with catalytic performance of the sample (i.e., SFO-3EG>SFO-6EG>SFO-1EG>SFO-bulk). The SFO-3EG catalyst performed the best, giving a T 50% of ca. 270°C and a T 90% of ca. 310°C at space velocity=5000mL/(g h). It is concluded that the good catalytic performance of SFO-3EG was associated with its large surface area, high oxygen adspecies concentration, and good low-temperature reducibility as well as the high-quality 3D macroporous structure. [Copyright &y& Elsevier]

Abstract: Porous Co3O4 nanowires and nanorods (Co3O4-HT, Co3O4-HT-PEG, Co3O4-HT-CTAB, and Co3O4-ME-CTAB, respectively) have been fabricated via the hydrothermal or microemulsion route in the absence and presence of polyethylene glycol (PEG) or cetyltrimethylammonium bromide (CTAB), respectively. Physicochemical properties of the materials were characterized by means of numerous techniques, and their catalytic activities for toluene combustion were evaluated. It is shown that Co3O4-HT-PEG and Co3O4-HT-CTAB displayed a porous nanowire-like morphology, whereas Co3O4-ME-CTAB exhibited a porous nanorod-like shape. The porous Co3O4 samples (surface area=47–52m2/g) possessed much higher surface oxygen adspecies concentrations and much better low-temperature reducibility than the nonporous counterpart. The Co3O4-HT-CTAB sample showed the highest catalytic performance (T 50% =195 and T 90% =215°C at a space velocity of 20,000mL/(gh)). It is concluded that the excellent catalytic performance of Co3O4-HT-CTAB was associated with its higher surface area and surface oxygen species concentration, and better low-temperature reducibility. [Copyright &y& Elsevier]

Abstract: Three-dimensionally ordered macroporous (3DOM) Eu0.6Sr0.4FeO3-supported cobalt oxide nanocatalysts (yCoO x /3DOM-ESFO; y wt%=1, 3, 6, and 10) were prepared using the incipient wetness impregnation method. Physicochemical properties of the composite materials were characterized by means of numerous techniques, and their catalytic performance was evaluated for the combustion of toluene. It is shown that all of the samples displayed a well-defined 3DOM architecture with a surface area of 22–31m2 g−1 and the loaded cobalt oxide nanoparticles with a diameter of 7–11nm were well dispersed on the surface of the 3DOM-ESFO support. Among the yCoO x /3DOM-ESFO samples, the 3CoO x /3DOM-ESFO and 6CoO x /3DOM-ESFO ones possessed the highest oxygen adspecies concentration and the best reducibility at low temperature, and hence showing the best catalytic performance (the temperatures required for 50 and 90% toluene conversions were ca. 250 and 270°C at a space velocity of 20,000mLg–1 h–1, respectively) for toluene combustion. The apparent activation energies (ca. 72kJmol−1) of 3CoO x /3DOM-ESFO and 6CoO x /3DOM-ESFO were lower than that (81kJmol−1) of 3DOM-ESFO. It is concluded that the enhanced catalytic performance of 3CoO x /3DOM-ESFO and 6CoO x /3DOM-ESFO for toluene combustion was mainly related to their higher oxygen adspecies concentrations, stronger reducibility at low temperature, and better dispersion of cobalt oxide nanoparticles. [Copyright &y& Elsevier]

Abstract: Three-dimensionally ordered macroporous (3DOM) perovskite-type oxides EuFeO3 (EFO-3DOM) and Eu0.6Sr0.4FeO3 (ESFO-3DOM) were prepared by the citric acid-assisted polymethyl methacrylate-templating method. The physicochemical properties of the materials were characterized by means of numerous techniques. Catalytic activities of these porous samples were evaluated for the combustion of toluene. It is shown that the EFO-3DOM and ESFO-3DOM catalysts were of high-quality 3DOM architecture and single-phase orthorhombic crystal structure with a surface area of 16–31m2/g. The sequence in surface oxygen species concentration and low-temperature reducibility decreased in terms of ESFO-3DOM>EFO-3DOM>EFO-bulk, in good agreement with the order in catalytic activity. The ESFO-3DOM catalyst exhibited the best performance, giving the T 10%, T 50%, and T 90% of 233, 278, and 305°C at a space velocity of 20,000mL/(gh), respectively. Apparent activation energies of the ESFO-3DOM, EFO-3DOM, and EFO-bulk catalysts were ca. 82, 96, and 104kJ/mol, respectively. The excellent catalytic activity of ESFO-3DOM might be associated with its higher surface area and surface oxygen species concentration and better low-temperature reducibility as well as high-quality 3DOM structure. [Copyright &y& Elsevier]

Abstract: Three-dimensionally ordered macroporous (3DOM) La0.6Sr0.4Fe0.8Bi0.2O3−δ (LSFB) were prepared using the surfactant (Pluronic F127, poly(ethylene glycol), l-lysine or xylitol)-assisted polymethyl methacrylate-templating method. Physicochemical properties of the materials were characterized by means of a number of analytical techniques, and their catalytic activities were evaluated for the combustion of toluene. It is shown that the LSFB samples were of 3DOM-architectured single-phase orthorhombic crystal structure. The nature of surfactant and solvent could influence the pore structures and surface areas of the LSFB samples. The Fe4+/Fe3+ or Oads/Olatt molar ratio and low-temperature reducibility correlated with the catalytic performance of the LSFB sample. The porous LSFB samples much outperformed the bulk counterpart, with the LSFB sample derived with xylitol showing the best catalytic activity (the temperatures required for 50 and 90% toluene conversions were 220 and 242°C at 20,000mL/(gh), respectively). Apparent activation energies of the porous LSFB samples were in the range of 46–74kJ/mol. It is concluded that the high oxygen adspecies concentration and good low-temperature reducibility were responsible for the excellent catalytic activity of the porous LSFB sample derived with xylitol. [Copyright &y& Elsevier]

Abstract: Three-dimensionally ordered macroporous (3DOM) and bulk Co3O4, Eu0.6Sr0.4FeO3 (ESFO), and 3 wt% Co3O4/Eu0.6Sr0.4FeO3 (3Co3O4/ESFO) were fabricated using the PMMA-templating (3DOM-Co3O4 and 3DOM-ESFO), citric acid-assisted hydrothermal (Co3O4-bulk and ESFO-bulk), and incipient wetness impregnation (3Co3O4/3DOM-ESFO and 3Co3O4/ESFO-bulk) methods, respectively. Physicochemical properties of these materials were characterized by means of various techniques, and their catalytic activities were evaluated for toluene combustion. Compared to the nonporous Co3O4 and ESFO samples, the 3DOM-Co3O4, 3DOM-ESFO, and 3Co3O4/3DOM-ESFO samples exhibited higher oxygen adspecies concentrations and better low-temperature reducibility. The 3Co3O4/3DOM-ESFO sample showed the best catalytic activity for toluene combustion, giving the T 50% and T 90% of 251 and 269°C at 20,000mL/(gh), respectively. The apparent activation energies of these samples were in the range of 72–88kJ/mol. We believe that the higher oxygen adspecies concentration, better low-temperature reducibility, and synergistic action between Co3O4 and 3DOM-structured ESFO were responsible for the excellent catalytic performance of 3Co3O4/3DOM-ESFO. [Copyright &y& Elsevier]

Abstract: Three-dimensionally (3D) ordered macroporous (3DOM) La0.6Sr0.4FeO3-δ (LSF-F127, LSF–PEG, LSF–PEG–EtOH, and LSF–Lysine) with mesoporous or nanovoid-like skeletons were prepared using the surfactant (Pluronic F127, poly(ethylene glycol) (PEG) or l–lysine)-assisted polymethyl methacrylate (PMMA)-templating method in aqueous or 40% ethanol aqueous solution. It is shown that the LSF samples displayed a 3DOM architecture and were of a single-phase orthorhombic crystal structure. The nature of surfactant and solvent could influence the pore structure and surface area of the final product. Treating the LSF precursor first in N2 at 500°C and then in air at 750°C favored the formation of 3DOM-structured La0.6Sr0.4FeO3−δ. The porous LSF catalysts performed well in toluene combustion, with LSF–PEG showing the best catalytic performance (T 10% =54°C, T 50% =225°C and T 90% =280°C at 20,000mL/(g h)). It is concluded that the excellent catalytic performance of 3DOM-structured LSF is associated with their larger surface areas, higher oxygen adspecies concentrations, better low-temperature reducibility, and high-quality 3DOM structures. [Copyright &y& Elsevier]

Abstract: The NiO samples (NiO-HMTA, NiO-HMTA-PEG, NiO-HMTA-PVP, and NiO-urea, respectively) with a surface area of 31−66m2/g and porous nanoflower- and nanourchin-like morphologies were prepared via the hydrothermal route with hexamethylenetetramine (HMTA) or urea as precipitator in the absence or presence of surfactant (poly(ethylene glycol) (PEG) or polyvinyl pyrrolidone (PVP)). It is shown that NiO-HMTA-PVP possessed the highest surface area and Oads concentration and the best reducibility. The NiO-HMTA-PVP catalyst performed the best (T 50% =253°C and T 90% =266°C). The excellent catalytic activity of NiO-HMTA-PVP was associated with its large surface area, high Oads concentration, and good reducibility. [Copyright &y& Elsevier]

Among the developed electrocatalysts, NiCr-layered double hydroxides (NiCr-LDH) are one of the most effective electrocatalytic materials for water oxidation. However, applications of such a kind of materials are practically limited due to their poor electric conductivity. In this work, the single-walled carbon nanotube (SWCNT) was doped to NiCr-LDH, and the LDH-based nanocomposites were synthesized using the one-step ultrasonic-assisted method. Physicochemical properties of the NiCr-LDH/SWCNT composites were characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), field emission−scanning electron microscopy (FE−SEM), and linear sweep voltammetry (LSV). The NiCr-LDH/SWCNT composites were used as effective nanomaterials for oxygen evolution reaction (OER) at a near neutral medium. The LSV results confirm that the overpotential of the NiCr-LDH/SWCNT-0.006 sample decreased to about 120 mV at pH = 9.5, as compared with that of the NiCr-LDH or NiCr-LDH-SWCNT-0.006 (prepared by the two-step method) sample. The high oxygen evolution activity of NiCr-LDH/SWCNT-0.006 was associated with the co-presence of the homogeneously dispersed NiCr-LDH, good electrochemical activity, and high electrical conductivity. In addition, the as-prepared optimized NiCr-LDH/SWCNT electrocatalyst was highly stable for the OER reaction. • SWCNT was doped in to NiCr-LDH using the one-step ultrasonic method. • Optimized NiCr-LDH/SWCNT shows overpotential of 120 mV at pH = 9.5 for OER. • The highly performance of NiCr-LDH/SWCNT is due to its fast charge transfer. [ABSTRACT FROM AUTHOR]

Abstract: Rhombohedrally crystallized three-dimensionally ordered macroporous (3DOM) perovskite-type oxides LaMnO3 with mesoporous skeletons were prepared using the poly(ethylene glycol) (PEG)- and/or l-lysine-assisted poly(methyl methacrylate) (PMMA)-templating method. Physicochemical properties of the materials were characterized by numerous analytical techniques. Catalytic performance of the as-prepared LaMnO3 samples was evaluated for the combustion of toluene. It is found that addition of appropriate amounts of PEG400 and l-lysine was beneficial for the generation of high-quality 3DOM-structured LaMnO3 (denoted as LaMnO3-PL-1, LaMnO3-PL-2, and LaMnO3-PL-3 derived with a PEG400/l-lysine molar ratio of 1.23, 0.61, and 0.31, respectively) with mesoporous skeletons and high surface areas (32–38m2/g). Among the LaMnO3 samples, the LaMnO3-PL-2 one possessed the largest surface area and the highest contents of surface Mn4+ and adsorbed oxygen species. 3DOM-structured LaMnO3 showed better low-temperature reducibility than bulk LaMnO3, with the LaMnO3-PL-2 sample displaying the best low-temperature reducibility. Under the conditions of toluene concentration=1000ppm, toluene/O2 molar ratio=1/400, and space velocity=20,000mL/(gh), the porous LaMnO3 catalysts remarkably outperformed the nonporous bulk counterpart; over the best-performing LaMnO3-PL-2 catalyst, the temperatures required for toluene conversion=50 and 90% were ca. 226 and 249°C, respectively. The apparent activation energies (58–61kJ/mol) for toluene combustion over the LaMnO3-PL-1–3 catalysts were much lower than that (97kJ/mol) over the bulk LaMnO3 catalyst. It is concluded that the large surface area, high oxygen adspecies content, good low-temperature reducibility, and unique bimodal pore structure were responsible for the good performance of 3DOM-architectured LaMnO3 with mesoporous skeletons for toluene combustion. [Copyright &y& Elsevier]

Abstract: Three-dimensionally ordered macroporous (3DOM) cubic perovskite-type oxides SrFeO3−δ were prepared using the citrate acid-assisted poly(methyl methacrylate)-templating method in the presence of ethylene glycol, sucrose or l-lysine (denoted as SFO-0, SFO-Sucrose, and SFO-Lysine, respectively). It is found that the SrFeO3−δ samples possessed a 3DOM architecture and were high in surface area (34–61m2/g). The porous SrFeO3−δ catalysts performed well in toluene combustion, with the SFO-0 sample exhibiting the highest catalytic activity (T 50% =292°C and T 90% =340°C at 20,000mL/(gh)). The catalytic activity of the samples showed a good relationship with surface area, oxygen adspecies concentration, and low-temperature reducibility, all decrease in the order of SFO-0>SFO-Lysine>SFO-Sucrose≫SFO-bulk. It is deduced that the good catalytic performance of the porous SrFeO3−δ materials is due to the good low-temperature reducibility, large surface area, and high oxygen adspecies concentration. [Copyright &y& Elsevier]

Abstract: Three-dimensionally ordered macroporous (3DOM) single-phase rhombohedral perovskite-type oxide LaMnO3 materials with nanovoid skeletons were prepared using the poly(methyl methacrylate)-templating methods with the assistance of surfactant (poly(ethylene glycol) (PEG) or triblock copolymer (Pluronic P123)). The nature of surfactant influenced the pore structure of the LaMnO3 sample. The use of PEG400 alone led to a 3DOM-structured LaMnO3 without nanovoid skeletons; with the addition of PEG400 and P123, however, one could prepare LaMnO3 samples with high-quality 3DOM structures, nanovoid skeletons, and high surface areas (37–39m2/g). Under the conditions of toluene concentration=1000ppm, toluene/O2 molar ratio=1:400, and space velocity=20,000mL/(gh), the porous LaMnO3 samples were superior to the bulk counterpart in catalytic performance, with the nanovoid-containing 3DOM-structured LaMnO3 catalyst performing the best (the temperatures for toluene conversions of 50% and 90% were 222–232 and 243–253°C, respectively). The apparent activation energies (57–62kJ/mol) over the 3DOM-structured LaMnO3 catalysts were much lower than that (97kJ/mol) over the bulk LaMnO3 catalyst. We believe that the excellent performance of the 3D macroporous LaMnO3 materials in catalyzing the combustion of toluene might be due to factors such as large surface area, high oxygen adspecies concentration, good low-temperature reducibility, and unique nanovoid-containing 3DOM structure of the materials. [Copyright &y& Elsevier]

Abstract: The three-dimensional (3D) macroporous orthorhombically crystallized perovskite-like oxides La2CuO4 were prepared using the polymethyl methacrylate (PMMA) microsphere-templating strategy with nitrates of lanthanum and copper as metal source and a mixed solution of methanol and ethylene glycol as solvent in the absence or presence of citric acid and after calcination at various atmospheres. The as-prepared materials were characterized by means of X-ray diffraction, N2 adsorption-desorption, scanning electron microscopy, X-ray photoelectron spectroscopy, and hydrogen temperature-programmed reduction. Catalytic activities of the materials were evaluated for the combustion of methane. The catalyst (La2CuO4-1) prepared with PMMA and citric acid possessed a 3D ordered macroporous (3DOM) structure and a surface area up to 46m2/g, whereas the one (La2CuO4-2) prepared with PMMA but without citric acid exhibited a 3D wormhole-like macroporous structure and a surface area of 39m2/g. There was the presence of a trace amount of La2O2CO3 phase in the La2CuO4-1 and La2CuO4-2 catalysts. The calcination procedure (first in N2 flow at 700°C and then in air flow at 300 and 800°C, respectively) was crucial in forming the 3D porous structure of La2CuO4. The as-obtained catalysts had overstoichiometric oxygen. The La2CuO4-1 catalyst showed better low-temperature reducibility than the La2CuO4-2 and La2CuO4-Citrate (derived from the conventional citric acid-complexing route) catalysts. The 3D porous La2CuO4 materials performed well in catalyzing the oxidation of methane, with the La2CuO4-1 catalyst showing the best performance (the temperature for 90% CH4 conversion=672°C (reaction rate=ca. 40mmol/(gh)) at CH4/O2 molar ratio=1/10 and space velocity=50,000mL/(gh). It is concluded that the excellent catalytic performance of La2CuO4-1 was mainly related to the higher surface area, better low-temperature reducibility, and 3DOM architecture. [Copyright &y& Elsevier]

Abstract: Three-dimensionally ordered macroporous (3DOM) europium oxide and samarium oxide with mesoporous walls and cubic crystal structures have been successfully fabricated with polymethyl methacrylate (PMMA) as hard template and F127, sucrose, and l-lysine as surfactant. The as-fabricated rare earth oxides were characterized by means of X-ray diffraction, thermogravimetric analysis, differential scanning calorimetric analysis, Fourier-transform infrared spectroscopy, scanning electron microscope, transmission electron microscopy, selected-area electron diffraction, nitrogen adsorption–desorption, ultraviolet–visible diffuse reflectance spectroscopy, and photoluminescence spectroscopy. It is shown that the as-fabricated Eu2O3 and Sm2O3 samples displayed 3DOM architectures with polycrystalline wormhole-like mesoporous walls. The nature of surfactant and solvent and calcination parameter had important effects on the pore structure and surface area of the final product. The introduction of surfactant and the carbonization of sucrose or l-lysine favored the enhancement in surface area of the 3DOM-structured materials, with the 3DOM Eu2O3 and Sm2O3 samples derived in the presence of sucrose possessing the highest surface area of 36.8 and 32.6m2 g−1, respectively. The 3DOM Eu2O3 and Sm2O3 samples showed much better UV-light absorption capacity than their bulk counterparts. The PL study revealed that the luminescent properties could be modified by tailoring the pore structure of Eu2O3 and Sm2O3. The unique physical properties associated with the generation of 3DOM skeletons and wormhole-like mesoporous walls make such materials useful for the applications in optics and heterogeneous catalysis. [Copyright &y& Elsevier]

Abstract: MgO nano/microparticles with multiple morphologies and porous structures have been fabricated via the surfactant (poly(N-vinyl-2-pyrrolidone, poly(ethylene glycol) (PEG), cetyltrimethylammonium bromide, oleylamine or triblock copolymer P123 or F127) assisted solvo- or hydrothermal route in a dodecylamine or oleic acid solvent. The as-fabricated MgO samples were characterized by means of numerous techniques. It is shown that the obtained MgO samples were single-phase and of cubic in crystal structure; the particle morphology and pore architecture mainly depended upon the surfactant, solvent, and solvo- or hydrothermal temperature adopted. The solvothermal process resulted in polycrystalline MgO, whereas the hydrothermal one gave rise to single-crystalline MgO. Surface areas (8–169m2 g−1) of the MgO samples derived solvothermally were lower than those (181–204m2 g−1) of the MgO counterparts derived hydrothermally, with the mesoporous MgO generated after the PEG-assisted hydrothermal treatment at 240°C for 72h possessing the highest surface area. CO2 adsorption capacities of the MgO samples were in good agreement with their surface areas, and the mesoporous MgO derived hydrothermally with PEG at 240°C for 72h exhibited the largest CO2 uptake (368μmolg−1) below 350°C. We believe that such a high low-temperature adsorption capacity renders the mesoporous magnesia material useful in the utilization of acidic gas adsorption. [Copyright &y& Elsevier]

Abstract: Bismuth vanadates with multiple morphologies and/or porous structures were prepared using the alcoho-hydrothermal strategy with bismuth nitrate and ammonium metavanadate as metal source, NaOH as pH adjustor, ethanol and ethylene glycol as solvent, and/or dodecylamine (DA), oleylamine (OL) or oleic acid (OA) as surfactant. The materials were characterized by means of the XRD, Raman, TGA/DSC, FT-IR, BET, SEM, TEM, XPS, and UV–vis techniques. The photocatalytic performance of the as-obtained samples was evaluated for the degradation of phenol in the presence of a small amount of H2O2 under visible-light irradiation, and the effect of phenol concentration on the photocatalytic activity was also examined. It is found that the surfactant and pH value had a significant influence on the particle morphology and even the crystalline structure of the product. Porous olive-like monoclinic BiVO4 samples could be prepared with DA, OL or OA as surfactant at pH=1.5 or 3.0 and alcoho-hydrothermal temperature=100°C. With DA as surfactant at an alcoho-hydrothermal temperature of 100°C, short-rod-like monoclinic BiVO4 and porous sheet-layered spherical orthorhombic Bi4V2O11 were obtained when the pH value of the precursor solution was raised to 7.0 and 11.0, respectively. Among the BiVO4 samples, the porous olive-like one with a surface area of 12.7m2/g exhibited the best visible-light-driven photocatalytic performance for phenol degradation. It is concluded that the excellent photocatalytic activity of the porous olive-like BiVO4 sample was associated with its higher surface area and surface oxygen vacancy density, porous structure, lower bandgap energy, and unique morphology. [Copyright &y& Elsevier]

Abstract: Three-dimensionally (3D) ordered and wormhole-like mesoporous iron oxides (denoted as Fe-KIT6 and Fe-CA) were respectively prepared by adopting the 3D ordered mesoporous silica KIT-6-templating and modified citric acid-complexing strategies, and characterized by a number of analytical techniques. It is shown that the Fe-KIT6-400 and Fe-CA-400 catalysts derived after 400°C-calcination possessed high surface areas (113–165m2/g), high surface adsorbed oxygen concentrations, and good low-temperature reducibility, giving 90% conversion below 189 and 208°C for acetone and methanol oxidation at 20,000mL/(g h), respectively. It is believed that the good catalytic performance of Fe-CA-400 and Fe-KIT6-400 was related to factors such as higher surface area and oxygen adspecies concentration, better low-temperature reducibility, and 3D mesoporous architecture. [Copyright &y& Elsevier]

Abstract: Rhombohedral chromia with three-dimensionally (3D) ordered mesopore structures were fabricated adopting the ultrasound-assisted nanocasting strategy with 3D ordered mesoporous silica (KIT-6) as hard template and chromium nitrate as metal source. The physicochemical properties of the materials were characterized by the XRD, TGA/DSC, BET, TEM/SAED, XPS, and H2-TPR techniques, and their catalytic activities were evaluated for the oxidation of typical volatile organic compounds (VOCs), such as formaldehyde, acetone, and methanol. It is found that there were tri-, penta-, and hexavalent chromium ions in the 3D mesoporous structure. Compared to the bulk chromia, the mesoporous chromia materials were larger in surface area (69–124m2/g) and could be reduced at lower temperatures. Among the chromia catalysts, the meso-Cr-400 one obtained after calcination at 400°C showed the best performance. Over meso-Cr-400 at space velocity=30,000mL/(gh), formaldehyde, acetone, and methanol conversions achieved 90% at 117, 124, and 130°C, respectively; the corresponding apparent activation energies were 45.6, 49.7, and 50.8kJ/mol. It is concluded that the ultrasound treatment was a key step to improve the mesoporosity quality of the chromia materials during the nanocasting process, and the factors, such as low-temperature reducibility, 3D ordered mesoporous architecture, and high-surface area, were responsible for the excellent catalytic performance of meso-Cr-400. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensional (3D) ordered mesoporous cubic Co3O4 (denoted as Co-KIT6 and Co-SBA16) were fabricated adopting the KIT-6- and SBA-16-templating strategies, respectively. It is shown that Co-KIT6 and Co-SBA16 possessed large surface areas (118–121m2/g), high oxygen adspecies concentrations, and good low-temperature reducibility. Over Co-KIT6 at space velocity=20,000mL/(gh), 90% toluene and methanol conversions were achieved at 180 and 139°C, respectively. The excellent catalytic performance of Co-KIT6 and Co-SBA16 was associated with their larger surface areas, higher oxygen adspecies concentrations, better low-temperature reducibility, and 3D ordered mesoporous structure. [ABSTRACT FROM AUTHOR]

Abstract: The photocatalyst TiO2 with a wormhole-like mesoporous structure and narrow pore distribution were successfully synthesized using triethanolamine as template. The complex oxides InVO4 with a relatively high surface area, a visible light active hydrogen-evolving photocatalyst, were obtained by means of the templating hydrothermal method with a variety of surfactants. InVO4 with wormhole-like structure were fabricated by templating of cetyltrimethylammonium bromide. By comparing with the non-mesoporous samples, the mesoporous photocatalysts exhibited higher photocatlytic hydrogen evolution activity for water splitting in the absence and in the presence of oxalic acid. [Copyright &y& Elsevier]

Abstract: Fluorite-type nanosized Ce0.60Zr0.35Y0.05O2 (nano-CZY) solid solution catalysts that are relatively uniform in particle size (4–5nm) and y CrO x /nano-CZY (y is the weight percentage of Cr2O3 ranging from 2 to 10wt%) catalysts were prepared by the ethylene glycol-assisted CTAB-templated co-precipitation and incipient wetness impregnation methods, respectively. The materials were characterized by a number of analytical techniques and their catalytic performance was evaluated for the oxidative dehydrogenation of isobutane. The y CrO x /nano-CZY catalysts show excellent activities, with the y =8wt% one performing the best (ca. 93% isobutene selectivity and ca. 10% isobutene yield at 540°C and 30,000mL/(gcat h)). We conclude that the good reducibility of the highly dispersed CrO x domains and the promotion of O2 adsorption at oxygen vacancies of nano-CZY (for enhanced oxidation of the reduced catalyst) are responsible for the excellent performance of the 8wt% CrO x /nano-CZY catalyst. [Copyright &y& Elsevier]

The oxidative dehydrogenation (ODH) of propane was investigated on vanadia dispersed on alumina containing a nominal polymolybdate monolayer (4.8 Mo/nm2). Dehydrogenation rates and selectivities on these catalysts were compared with those on vanadia domains dispersed on alumina. At a given vanadia surface density, ODH reaction rates per gram of catalyst were about 1.5–2 times greater on MoOx-coated Al2O3 than on pure Al2O3 supports. The higher activity of vanadia dispersed on MoOx-coated Al2O3 reflects the greater reducibility of VOx species as a result of the replacement of V&z.sbnd;O&z.sbnd;Al with V&z.sbnd;O&z.sbnd;Mo bonds. The MoOx interlayer also increased the alkene selectivity by inhibiting propane and propene combustion rates relative to ODH rates. This appears to reflect a smaller number of unselective V2O5 clusters when alkoxide precursors are used to disperse vanadia on MoOx/Al2O3 as compared to the use of metavanadate precursor to disperse vanadia on pure Al2O3. At 613 K, the ratio of rate coefficients for propane combustion and propane ODH was three times smaller on MoOx/Al2O3 than on Al2O3 supports. The ratio of rate constants for propene combustion and propane ODH decreased by a similar factor. [Copyright &y& Elsevier]

Highly dispersed Ag nanoparticles supported on high-surface-area 3DOM La0.6Sr0.4MnO3 were successfully generated via the dimethoxytetraethylene glycol-assisted gas bubbling reduction route. The macroporous materials showed super catalytic performance for methane combustion. [ABSTRACT FROM AUTHOR]

• PdPtV nanoparticles (NPs) are synthesized using the oil-phase co-reduction strategy. • The PdPtV/CeO 2 −ZrO 2 catalyst performs the best in ethylbenzene (EB) oxidation. • PdPtV/CeO 2 −ZrO 2 shows large EB adsorption capacity, good reducibility, and strong surface acidity. • TPD and in situ DRIFTS are used to study the reversible poisoning of PdPtV/CeO 2 −ZrO 2 by SO 2. • V doping to PdPt NPs protects the active PdPt sites from being poisoned by SO 2. The PdPtVO x /CeO 2 −ZrO 2 (PdPtVO x /CZO) catalysts were obtained by using different approaches, and their physical and chemical properties were determined by various techniques. Catalytic activities of these materials in the presence of H 2 O or SO 2 were evaluated for the oxidation of ethylbenzene (EB). The PdPtVO x /CZO sample exhibited high catalytic activity, good hydrothermal stability, and reversible sulfur dioxide-poisoning performance, over which the specific reaction rate at 160°C, turnover frequency at 160°C (TOF Pd or Pt), and apparent activation energy were 72.6 mmol/(g Pt ⋅sec) or 124.2 mmol/(g Pd ⋅sec), 14.2 sec−1 (TOF Pt) or 13.1 sec−1 (TOF Pd), and 58 kJ/mol, respectively. The large EB adsorption capacity, good reducibility, and strong acidity contributed to the good catalytic performance of PdPtVO x /CZO. Catalytic activity of PdPtVO x /CZO decreased when 50 ppm SO 2 or (1.0 vol.% H 2 O + 50 ppm SO 2) was added to the feedstock, but was gradually restored to its initial level after the SO 2 was cut off. The good reversible sulfur dioxide-resistant performance of PdPtVO x /CZO was associated with the facts: (i) the introduction of SO 2 leads to an increase in surface acidity; (ii) V can adsorb and activate SO 2 , thus accelerating formation of the SO x 2− (x = 3 or 4) species at the V and CZO sites, weakening the adsorption of sulfur species at the PdPt active sites, and hence protecting the PdPt active sites to be not poisoned by SO 2. EB oxidation over PdPtVO x /CZO might take place via the route of EB → styrene → phenyl methyl ketone → benzaldehyde → benzoic acid → maleic anhydride → CO 2 and H 2 O. [Display omitted] [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen evolution (PHE) from water splitting is a promising technology for clean and renewable energy production. Elemental crystalline red phosphorus (CRP) is purposefully designed and developed for PHE reaction. However, the photocatalytic activity of CRP is limited by its intrinsic P vacancy (VP) defects, which lead to detrimental charge trapping at deep states and hence its severe recombination. To address this issue, a boron (B) incorporated CRP (B‐CRP) photocatalyst is tailored, synthesized via a simple and mild boric acid‐assisted hydrothermal strategy. The incorporation of B effectively fills the VP defects, reducing deep trap states (DTS) and introducing beneficial shallow trap states (STS) within the band structure of CRP. This defect engineering approach leads to enhanced photocatalytic activity, with B‐CRP achieving a PHE rate of 1392 µmol g−1 h−1, significantly outperforming most reported elemental photocatalysts in the literature. Density functional theory (DFT) simulations and ultrafast spectroscopy support the constructive role of B‐dopant‐induced STS in prolonging active charge carrier lifetimes, promoting more efficient photocatalytic reactions. The findings not only demonstrate the effectiveness of B‐CRP as a photocatalyst but also highlight the usefulness of dopant‐induced STS in advancing PHE technologies. [ABSTRACT FROM AUTHOR]

It is possible to remove volatile organic compounds containing chlorine (CVOCs, such as chlorobenzene) in a single device designed for selective catalytic reduction of NOX with NH3 for the industries containing CVOCs and NOX. Breaking the efficiency-selectivity trade-off in chlorobenzene oxidation remains a major challenge due to the conjugation of halogen atoms with the benzene ring and the reducing nature of NH3. A stepwise synthesis strategy is demontrated to disperse dual Ru/Cu Lewis acid sites outside and inside the zeolite channel. Under the confinement of zeolite, the Ru4+ Lewis acid site on the external surface of the zeolite promotes chlorobenzene oxidation by weakening the p-n conjugate structure of Cl and benzene ring, while the Cu2+ Lewis acid site within the internal channel converts NOX and NH3 to N2. The mutual interference between catalytic oxidation and reduction is successfully avoided. Therefore, the low toxic CO2 and HCl selectivity experience a considerable increase from 21% to 86%, and from 51% to 94% with 91% conversion of chlorobenzene, while maintaining excellent elimination performance for NO (with N2 selectivity exceeding 90%). The incorporation of separated active sites and reaction spaces into the design may offer potentials for other energy and environmental applications. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C 3 N 4) has been demonstrated as a promising non-metal material for photocatalytic hydrogen evolution (PHE), while its photocatalytic activity is greatly limited due to the narrow visible light response-ability and the intrinsic severe charge deep trapping and recombination effects. Herein, a co-functionalized g-C 3 N 4 system by Se doping and nitrogen vacancies modification is developed through a Se vapor-assisted-chemical vapor deposition synthetic strategy. Advanced characterization results revealed that Se dopants promote the visible-light absorption ability of g-C 3 N 4 , while nitrogen defects-induced shallow trap states are constructive to improving charge separation/transportation efficiency by effectively retarding the detrimental charge deep trapping and recombination. As a result, the synergistic effect of the Se dopants and nitrogen defects leads to a highly efficient PHE performance of g-C 3 N 4. The integrated engineering strategy and mechanism understanding provided in this work may offer new insights into developing other novel photocatalysts for various applications. [Display omitted] • V N -rich Se-doped g-C 3 N 4 is constructed by a Se vapor-assisted-CVD strategy. • Se doping improves the visible light absorption ability of g-C 3 N 4. • V N -induced shallow trap states promote charge separation/transportation efficiency. • The synergy of V N and Se dopants leads to superior visible-light PHE activity. [ABSTRACT FROM AUTHOR]

The emission of methane leads to the increase in the methane concentration in the atmosphere, which not only wastes resources but also intensifies the greenhouse effect and brings about serious environmental problems. Catalytic combustion can completely convert methane into carbon dioxide and water at low temperatures. However, the catalytic activities of the conventional supported palladium catalysts (e.g., Pd/Al2O3 and Pd/ZrO2) are easy to decrease or the two catalysts can even be deactivated under actual harsh reaction conditions (high temperatures, steam- and sulfur dioxide-containing atmospheres, etc.). Recently, noble metal catalysts supported on zeolites with ordered pores and good thermal stability have attracted much attention. This review article summarizes the recent progress on the development and characteristics of zeolite-supported noble metal catalysts for the combustion of methane. The effects of framework structures, silica/alumina ratios, acidity, doping of alkali metals or transition metals, particle sizes and distributions, and their locations of/in the zeolites on methane combustion activity are discussed. The importance of developing high-performance catalysts under realistic operation conditions is highlighted. In addition, the related research work on catalytic methane combustion in the future is also envisioned. [ABSTRACT FROM AUTHOR]

Light-driven photothermocatalytic oxidation is a promising method for the elimination of volatile organic compounds (VOCs). The Co 3 O 4 , 0.46 Pt/Co 3 O 4 and 0.97 Pt/Co 3 O 4 catalysts were fabricated via the simple molten salt and incipient wetness impregnation method. Compared with Co 3 O 4 and 0.46 Pt/Co 3 O 4 , the 0.97 Pt/Co 3 O 4 catalyst showed higher photothermocatalytic performance for toluene oxidation under simulated solar irradiation intensity of 900 ​mW ​cm−2, with the toluene conversion and CO 2 yield being up to 98.3 % and 96.0 %, respectively. The better activity was ascribed to its outstanding strong light absorption and low temperature reducibility. Meanwhile, 0.97 Pt/Co 3 O 4 also exhibited an excellent photothermocatalytic stability and H 2 O resistance. The Vis−IR light played a key role in the photothermocatalytic oxidation of toluene in the whole solar spectrum. This work benefited the synthesis of catalysts with good photothermocatalytic activity for environment friendly treatment of VOCs. [ABSTRACT FROM AUTHOR]

1 ​wt% Ru/5 ​wt% Nb 2 O 5 /CeO 2 (RuNbCe) catalyst was synthesized via the incipient wetness impregnation method, and measured for the catalytic oxidation of dichloromethane (DCM). The physicochemical properties of catalysts were determined used various characterization techniques. Compared with 1 ​wt% Ru/CeO 2 , 5 ​wt% Nb 2 O 5 /CeO 2 , CeO 2 , 1 ​wt% Ru/ x Nb 2 O 5 /CeO 2 (x ​= ​1 ​wt%, 2 ​wt%, and 3 ​wt%) and 1 ​wt% Ru/ yM O n /CeO 2 (M ​= ​Co, Cr, Fe, Mg, Cu; y ​= ​5 ​wt%), the addition of 5 ​wt% Nb 2 O 5 obviously improved the catalytic performance of 1 ​wt% Ru/CeO 2 , with the T 90% and apparent activation energy (E a) being 287 oC and 43.5 ​kJ/mol, respectively, and less formation of polychlorinated byproducts at space velocity (SV) ​= ​15,000 ​mL ​g‒1 ​h‒1. The RuNbCe catalyst showed good thermal and hydrothermal stability, as well as HCl-resistance performance. We deduced that the higher oxidation performance of the RuNbCe catalyst may be attributed to the suitable acidic sites, good redox capacity, high surface adsorbed oxygen species concentration, and the strong interaction among Ru, Nb 2 O 5 and CeO 2. The RuNbCe catalyst has the potential to be applied for the elimination of chlorinated volatile organic compounds (CVOCs). [Display omitted] • Ru/Nb 2 O 5 /CeO 2 catalyst is prepared by an incipient wetness impregnation method. • Ru/Nb 2 O 5 /CeO 2 exhibits high catalytic activity for dichloromethane removal. • Ru/Nb 2 O 5 /CeO 2 shows high (hydro-)thermal stability and HCl-resistance. • High performance relates to acidity, redox capacity, O ads , and strong interaction. [ABSTRACT FROM AUTHOR]