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The influence of the surface chemical properties of the carbon support on the Pd dispersion, activity and stability of Pd(OH)2/C catalyst for the hydrogenolytic debenzylation of tetraacetyldibenzylhexaazaisowurtzitane (TADB) was studied in detail. The flowerlike nanosheet carbon material (NSC) was chosen as the pristine support, meanwhile chemical oxidation with nitric acid and physical calcination at 600 °C treatments were used to modify its surface properties, which were denoted as NSCox-2 (treated with 20 wt% HNO3) and NSC-600, respectively. The three carbon supports and the corresponding catalysts of Pd/NSC, Pd/NSC-600, and Pd/NSCox-2 were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), nitrogen sorption isotherm measurement (BET), powder X-ray diffraction (XRD), Raman spectra, X-ray photoelectron spectra (XPS), temperature-programmed desorption (TPD), temperature-programmed reduction (H2-TPR), thermogravimetric analysis (TG), and element analysis. The debenzylation activities of Pd/NSC, Pd/NSC-600, and Pd/NSCox-2, as well as the three catalysts after pre-reduction treatment were also evaluated. It was found that the activity and stability of the Pd(OH)2/C catalysts in the debenzylation reaction highly depended on the content of surface oxygen-containing groups of the carbon support.

Photoelectrochemical (PEC) splitting of water over a semiconductor is an ideal and clean way to produce hydrogen by using solar energy. Herein, a photoanode of TiO2 nanotube arrays (TNTA) was decorated with environment-friendly Cu-based nanomaterials through a two-step electrochemical process, followed by sensitization with eosin Y dye, for PEC water splitting. The confirmations of Cu and CuO on the surface of TNTA were recorded by XRD combined with XPS techniques. The obtained Cu-CuO/TNTA and Eosin Y/Cu-CuO/TNTA electrodes exhibit good light absorption abilities in the range of 380–600 nm, and the adsorption of Eosin Y is enhanced. Based on the analysis of the charge transfer resistance and energy levels of Cu, CuO, TiO2, and eosin Y, it can be found that the deposition of Cu-CuO and eosin Y on TNTA can greatly accelerate the interface charge transfer, resulting in enhanced PEC performances. Moreover, the plasmonic Cu and eosin Y can help to harvest more visible light and further improve the photocurrent density.

A reliable in situ self-generating template strategy has been developed for the synthesis of flowerlike carbon nanosheets by hydrothermal carbonization in the presence of both silica and zinc acetate using glucose as the carbon source. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), powder X-ray diffraction (XRD), Raman spectroscopy, nitrogen sorption isotherm measurement (BET) and element analysis revealed the morphology, crystal phase structure, porosity and chemical composition. The formation of the zinc silicate nanosheet template was due to the hydrolysis of amorphous silica and self-assembly under hydrothermal conditions. The resulting flowerlike carbon nanosheets proved to be an excellent palladium catalyst support.

TiO 2 with Nanoring/Nanotube (R/T) hierarchical structure can be prepared by tuning the oxidation time and oxidation voltage in the second step anodization. The resulting multiabsorption oscillating peaks in the visible light region present a strong dependence on the tube length which are derived from the interference of light reflected from the top nanorings and the bottom Ti substrate, and the optical path length in TiO 2 R/T hierarchical structure can be estimated as about 2 μm. The tube length of the as-prepared TiO 2 photoelectrode affects greatly its saturation photocurrent density, and the different tube-wall thickness can change the photocurrent-saturation potential. Under simulated AM 1.5 irradiation (100 mW/cm 2 ), TiO 2 R/T hierarchical structure with tube diameters of 20–40 nm and tube length of about 1.5 μm shows higher photocurrent density and hydrogen production rate at the bias of 0 V (vs. Ag/AgCl). The results from the IPCE plots and I-t curves verify that TiO 2 R/T hierarchical structure can exhibit the visible light activity, which is more related to the absorption induced by the defects rather than oscillating peaks. Based on the unique multiple light reflection in TiO 2 R/T hierarchical structure, surface treatment will pave a way for the better utilization of oscillating peaks in the visible light region.

CeO2/TiO2 catalysts were fabricated by dry ball milling in the presence or absence of an organic ligand. It was found that the catalysts prepared by ligand-assisted ball milling exhibited high NH3-SCR activities due to the interaction between cerium ions and ligand molecules resulting in good dispersion, a high Ce3+ ratio and high reducibility of cerium species.

In the present study, a series of CeO2/TiO2 catalysts were fabricated by dry ball milling method in the absence and presence of organic assistants, and their catalytic performances for the selective catalytic reduction (SCR) of NO by NH3 were investigated. It was found that the addition of organic assistants in the ball milling process and the calcining ambience exerted a significant influence on the catalytic performances of CeO2/TiO2 catalysts. The nitrogen sorption isotherm measurement (BET), powder X-ray diffraction (XRD), Raman spectra, high-resolution transmission electron microscopy (HR-TEM), hydrogen temperature-programmed reduction (H2-TPR), ammonia temperature-programmed desorption (NH3-TPD), sulfur dioxide temperature-programmed desorption (SO2-TPD), thermogravimetric analysis (TG), Fourier transform infrared (FT-IR) and X-ray photoelectron spectra (XPS) characterizations showed that the introduction of citric acid in the ball milling process could significantly change the decomposition process of the precursor mixture, which can lead to improved dispersion and reducibility of cerium species, surface acidity as well as the surface microstructure, all which were responsible for the high low temperature activity of CeTi-C-N in an NH3-SCR reaction. In contrast, the addition of sucrose in the milling process showed an inhibitory effect on the catalytic performance of CeO2/TiO2 catalyst in an NH3-SCR reaction, possibly due to the decrease of the crystallinity of the TiO2 support and the carbon residue covering the active sites.

A highly porous metal–organic framework based on supramolecular building blocks with pcu-topology (pcu-MOF) has been tested for the oxidative coupling of amines and disulfides or thiols to afford the N-sulfenylimines directly in good yields without the formation of N-sulfinyl- and N-sulfonylimines. The pcu-MOF catalyst could be easily recovered from the reaction mixture by simple filtration, and could be reused at least five times without any substantial loss in the yield. The control experiments and mechanistic studies suggested that the oxidative coupling process involved the imine formation and the N–S coupling reaction.

Reaction of 1,1-bis-[3,5-bis(carboxy) phenoxy]methane (H 4 L) and CuCl 2 in the presence of meso -tetrakis[4-(nicotinoyloxy)phenyl]porphyrin (TNPP) and manganese complex of TNPP (MnTNPP), respectively, under solvothermal condition afforded CuTNPP@MOF and MnTNPP@MOF, microporous metal-organic materials containing neutral CuTNPP or MnTNPP molecules in their frameworks. The nitrogen sorption isotherm measurement, ultraviolet visible adsorption spectroscopy (UV–vis), powder X-ray diffraction (XRD), and thermogravimetric analysis (TGA) characterizations showed that CuTNPP@MOF and MnTNPP@MOF were permanently porous and had heterogeneous catalytic activity for the oxidation of 3,5-di-tert-butylcatechol.

Porous S-doped bismuth vanadate with an olive-like morphology and its supported iron oxide (y wt.% FeOx/BiVO4-deltaS0.08, 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.% FeOx/BiVO4-deltaS0.08 photocatalysts contained a monoclinic scheetlite BiVO4 phase with a porous olive-like morphology, a surface area of 8.8-9.2 m2/g, and a bandgap energy of 2.38-2.42 eV. There was co-presence of surface Bi5+, Bi3+, V5+, V3+, Fe3+, and Fe2+ species in y wt.% FeOx/BiVO4-deltaS0.08. The 1.40 wt.% FeOx/BiVO4-deltaS0.08 sample performed the best for Methylene Blue degradation under visible-light illumination. The photocatalytic mechanism was also discussed. We believe that the sulfur and FeOx co-doping, higher oxygen adspecies concentration, and lower bandgap energy were responsible for the excellent visible-light-driven catalytic activity of 1.40 wt.% FeOx/BiVO4-deltaS0.08.

Cylinder- and cake-like Cr 2 O 3 with a rhombohedral structure were fabricated using the hydrothermal and microemulsion methods, respectively. It is found that surface areas, surface Cr 6 + and oxygen adspecies concentrations, and low-temperature reducibility of cake-like Cr 2 O 3 were much higher or better than those of the bulk counterpart. The cake-like Cr 2 O 3 sample showed the best catalytic performance for toluene combustion, giving the T 50% and T 90% of 229 and 240 °C at SV = 20,000 mL/(g h), respectively. The excellent catalytic performance of cake-like Cr 2 O 3 was associated with its oxygen adspecies concentration and good low-temperature reducibility.

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. 46 m2/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 (T50% = 256 °C and T90% = 278 °C at SV = 20,000 mL/(g h)) for toluene combustion of NiO-CTAB-2 was related to its larger surface area, higher oxygen adspecies concentration, and better low-temperature reducibility.

Porous Co 3 O 4 nanowires and nanorods (Co 3 O 4 -HT, Co 3 O 4 -HT-PEG, Co 3 O 4 -HT-CTAB, and Co 3 O 4 -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 Co 3 O 4 -HT-PEG and Co 3 O 4 -HT-CTAB displayed a porous nanowire-like morphology, whereas Co 3 O 4 -ME-CTAB exhibited a porous nanorod-like shape. The porous Co 3 O 4 samples (surface area = 47–52 m 2 /g) possessed much higher surface oxygen adspecies concentrations and much better low-temperature reducibility than the nonporous counterpart. The Co 3 O 4 -HT-CTAB sample showed the highest catalytic performance ( T 50% = 195 and T 90% = 215 °C at a space velocity of 20,000 mL/(g h)). It is concluded that the excellent catalytic performance of Co 3 O 4 -HT-CTAB was associated with its higher surface area and surface oxygen species concentration, and better low-temperature reducibility.

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 T50% and T90% of 251 and 269 °C at 20,000 mL/(g h), respectively. The apparent activation energies of these samples were in the range of 72–88 kJ/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.

The NiO samples (NiO-HMTA, NiO-HMTA-PEG, NiO-HMTA-PVP, and NiO-urea, respectively) with a surface area of 31 −66 m2/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 (T50% = 253 °C and T90% = 266 °C). The excellent catalytic activity of NiO-HMTA-PVP was associated with its large surface area, high Oads concentration, and good reducibility.

The rod-like tetragonal α-MnO 2 , flower-like hexagonal ɛ-MnO 2 , and dumbbell-like tetragonal β-MnO 2 were prepared using the hydrothermal or water-bathing method under different conditions. It is shown that the α-MnO 2 , ɛ-MnO 2 , and β-MnO 2 catalysts possessed a surface area of ca. 53, 30, and 114 m 2 /g, respectively. The oxygen adspecies concentration and low-temperature reducibility decreased in the order of α-MnO 2 > ɛ-MnO 2 > β-MnO 2 , coinciding with the sequence of their catalytic activities for toluene combustion. The well-defined morphological MnO 2 catalysts performed much better than the bulk counterpart. At a space velocity of 20,000 mL/(g h), the temperature for 90% toluene conversion was 238, 229, and 241 °C over α-MnO 2 , ɛ-MnO 2 , and β-MnO 2 , respectively. The apparent activation energies of α-MnO 2 , ɛ-MnO 2 , and β-MnO 2 were in the range of 20–26 kJ/mol. It is concluded that higher oxygen adspecies concentrations and better low-temperature reducibility were responsible for the good catalytic performance of the α-MnO 2 , ɛ-MnO 2 , and β-MnO 2 materials.

Nanosized rod-like, wire-like, and tubular α-MnO(2) and flower-like spherical Mn(2)O(3) have been prepared via the hydrothermal method and the CCl(4) solution method, respectively. The physicochemical properties of the materials were characterized using numerous analytical techniques. The catalytic activities of the catalysts were evaluated for toluene oxidation. It is shown that α-MnO(2) nanorods, nanowires, and nanotubes with a surface area of 45-83 m(2)/g were tetragonal in crystal structure, whereas flower-like spherical Mn(2)O(3) with a surface area of 162 m(2)/g was of cubic crystal structure. There were the presence of surface Mn ions in multiple oxidation states (e.g., Mn(3+), Mn(4+), or even Mn(2+)) and the formation of surface oxygen vacancies. The oxygen adspecies concentration and low-temperature reducibility decreased in the order of rod-like α-MnO(2) > tube-like α-MnO(2) > flower-like Mn(2)O(3) > wire-like α-MnO(2), in good agreement with the sequence of the catalytic performance of these samples. The best-performing rod-like α-MnO(2) catalyst could effectively catalyze the total oxidation of toluene at lower temperatures (T(50%) = 210 °C and T(90%) = 225 °C at space velocity = 20,000 mL/(g h)). It is concluded that the excellent catalytic performance of α-MnO(2) nanorods might be associated with the high oxygen adspecies concentration and good low-temperature reducibility. We are sure that such one-dimensional well-defined morphological manganese oxides are promising materials for the catalytic elimination of air pollutants.

The interaction of a cationic water-soluble porphyrin, 5,10,15,20-tetrakis [4-(3-pyridiniumpropoxy)phenyl]porphyrin tetrakisbromide (TPPOC3Py), with anionic surfactant, sodium dodecyl sulfate (SDS), in aqueous solution has been studied by means of UV–vis, 1H NMR, fluorescence, circular dichroism (CD) spectra and dynamic laser light scattering (DLLS), and it reveals that TPPOC3Py forms porphyrin-surfactant complexes (aggregates), including ordered structures J- and H-aggregates, induced by association with surfactant monomers below the SDS critical micelle concentration (cmc), and forms micellized monomer upon the cmc, respectively. The position of TPPOC3Py in the micelle is determined, which is not in the micelle core instead of intercalated among the SDS chains, most likely with the pyridinium group extending into the polar headgroup region of the micelle.

The interaction of a cationic water-soluble porphyrin, 5,10,15,20-tetrakis[4-(3-pyridiniumpropoxy)phenyl]prophyrin tetrakisbromide (TPPOC3Py), with beta-CD and HP-beta-CD in aqueous solution has been studied by UV-vis, 1H NMR, 2D-NOESY and MALDI-TOF MS, and it reveals that a stable 1:1 inclusion complex between TPPOC3Py and HP-beta-CD or beta-CD has formed, in which one of the meso substituents of porphyrin ring has deeply penetrated through the cavity of HP-beta-CD from secondary face. The inclusion constants of the complexes of TPPOC3Py-beta-CD and TPPOC3Py-HP-beta-CD are (1.6+/-0.2)x10(3) M-1 and (8.9+/-0.4)x10(4) M-1, respectively.

A flexible ligand with two 1,3-benzenedicarboxylate units has been used to construct a microporous metal–organic framework with pcu topology based on supramolecular building blocks (SBBs). The obtained Cu(II) MOF exhibits a noticeable CO2 adsorption hysteresis and a comparable methane adsorption capacity at room temperature.