Sustainable societies require development of cost-effective methods for harnessing energy from wastes and wastewater, and alternatively capturing this energy to make other useful chemicals with simultaneous wastes and wastewater treatment. Recently developed bioelectrochemical systems (BESs) that use microorganisms to catalyze different electrochemical reactions are promising for capturing the energy in wastes and wastewater for diverse purposes. A BES is called a microbial fuel cell (MFC) if electricity is generated and the Gibbs free energy change of the corresponding reaction is negative. Conversely, when the Gibbs free energy change of the overall reaction is positive, power needs to be supplied to drive this non-spontaneous reaction, and this BES is regarded as a microbial electrolysis cell (MEC). The electrode character is considered to be a key factor for triggering the applicable BESs. Graphene has been recently used as the electrode and investigated in BESs because of its unique structure and excellent properties. Here, an up-to-date review is provided on the recent research and development in BES-based graphene, particularly in MFC-based graphene. The recent pristine graphene, doped graphene, and supported graphene research in MFCs is described in detail. The potential applications of graphene in MECs and the scientific and technical challenges are also discussed.

The kinetics of the catalytic ignition processes of hydrogen/n-butane/air on Pt surface is studied to reveal the catalytic ignition mechanism. It is found that the ignition temperature of n-butane is lower when a certain amount of hydrogen is added. However, the effect of hydrogen on the catalytic ignition process and temperature of n-butane depends on the percentage of hydrogen added. When a small amount of hydrogen is added, it has a thermal effect. Adding more hydrogen gas causes it to have a chemical effect. A od fit is obtained between simulated and experimental data for the catalytic ignition temperatures. The ranges of hydrogen content with different effects are also predicted. Furthermore, this kinetic study shows that a different onset reaction of n-butane will lead to different ignition temperatures and mechanisms.

Resonance Raman spectra at five excitations covering the A- and B-band absorptions of 1-methylthymine (MT) were acquired. The Franck-Condon region structural dynamics and electronic transitions of MT were studied in conjunction with density functional theory calculations. The A- and B-band absorptions are assigned as π_H→π_L^*/π_H-2→π_L+2^* and π_H→π_L+2^*/π_H-2→π_L^* transitions, respectively, using the B3LYP/6-311 + G(d,p) level of theory. The hyper-conjugation interaction between the CH₃ group and pyrimidine ring leads to a noticeable red-shift in λ_max of the A-band absorption for MT, relative to that for thymine. It also significantly affects the Franck-Condon region structural dynamics of MT. The A- and B-band resonance Raman spectra are respectively assigned as the 14 and 11 fundamentals, their overtones and combination bands.The A-band resonance Raman intensities of MT are dominated by the v₉ (C5＝C6 stretching + C6H12 in-plane bending), v₁₆(ring deformation) and v₁₈ (N3C2N1 asymmetric stretching+C4C5C10 asymmetric stretching) modes. This indicates that the structural dynamics of MT are mainly along these reaction coordinates. The effect of solvent on the structural dynamics was examined. The Raman activity of the v₈(C4＝O9 stretching+N3H11 in-plane bending) vibrational mode is tuned by solvent, and the dependence of the normal mode displacement of v₈ on solvent is similar to that for thymine.

Microporous cobalt phosphate structures can be synthesized using ethylenediamine as a structure directing agent. During the syntheses of CoPO-en-1, CoPO-en-2, CoPO-en-3, and CoPO-en-4, it was found that they could interconvert during hydrothermal or calcination conditions. CoPO-en-2 and CoPO-en-4 are the crystallization intermediates of CoPO-en-1 and CoPO-en-3, respectively. During hydrothermal synthesis, CoPO-en-2 and CoPO-en-4 could be obtained at lower temperature or higher temperature during the initial crystallization stage. Extended synthesis time at higher temperature the two former structures transform into the two latter. CoPO-en-2, CoPO-en-3, and CoPO-en-4 could also convert to CoPO-en-1 during calcination, and these transformations indicated the sequence of structure stability. During synthesis under hydrothermal conditions, CoPO-en-2, CoPO-en-3, and CoPO-en-4 could convert to CoPO-en-1. During muffle furnace roasting, CoPO-en-2, CoPO-en-3, and CoPO-en-4 could also convert to CoPO-en-1. Different structures in the liquid or solid phases could be transformed into the same structure using different approaches.

Density functional theory (DFT) based on the plane wave basis set was used to investigate the geometries, electronic structures, and linear and second-order nonlinear optical properties of a series of AgGa(S_1-xSe_x)₂ solid solutions with chalcopyrite structures. The compounds showed similar band structures, and band gaps decreased with increasing x value. When 22.56% Hartree-Fock exchange was employed, the solid solution band gaps predicted by hybrid PBE functionals were consistent with experimental values. The optical properties of AgGa(S_1-xSe_x)₂ solid solutions, including refractive index, birefringence, reflectivity, adsorption coefficient, and second harmonic generation coefficient, changed regularly with composition. The range of variation was between that for AgGaS₂ and AgGaSe₂. The results indicated that crystals with specialized optical performances could be designed.

The structural, elastic, electronic, and optical properties of zinc-blende MTe (M=Zn/Mg) compounds were studied. The ultrasoft pseudopotential plane wave (PP-PW) method, based on density functional theory (DFT) within generalized gradient approximation (GGA), was used. Hybrid density functionals were applied to correct band gaps. Cubic ZnTe and MgTe are both direct band gap semiconductors, and calculated lattice parameters, elastic constants, and bulk moduli agree with previous results. Debye temperatures deduced from elastic constants for ZnTe and MgTe are 758 and 585 K, respectively. The dielectric function, refraction index, reflectivity and energy loss spectra were obtained and analyzed based on electronic band structures and densities of states.

First-principles calculations based on density functional theory (DFT) with the generalized gradient approximation (GGA-PW91) have been used to investigate the adsorption and dissociation of H₂O molecules on HfO₂(111) and (110) surfaces at different sites with different coverages. It was found that the surface hafnium atom was the active adsorption position of the (111) and (110) surfaces when compared different adsorption energies and various geometrical parameters. Adsorption energies of water on the HfO₂ (111) and (110) surfaces varied slightly as the coverage increased. It was shown that the most favorable configuration of H₂O on the HfO₂(111) and (110) surfaces corresponded to the coordination of H₂O via its oxygen to a surface hafnium atom. Adsorption geometries, Mulliken population charges, density of states, and frequency calculations for HfO₂-OH, HfO₂-O, and HfO₂-H at both surfaces were also carried out. The results showed that the hydroxyl group interacted with the surface by its oxygen atom to surface hafnium atoms. Isolated oxygen atoms bound to surface hafnium and oxygen atoms, while hydrogen atoms interact only with surface oxygen atoms to form hydroxyl groups. For the dissociation reaction, according to transition searching, H₂O→H (ads)+OH (ads). The energy barriers were endothermic by 9.7 and 17.3 kJ· mol^-1 for the (111) surfaces and exothermic by -59.9 and -47.6 kJ·mol^-1 for the (110) surfaces.

The dissolution process of an aluminum electrode in Lewis acidic ionic liquid aluminum chloride (AlCl₃)-1-butyl-3-methylimidazolium chloride (BMIC) was studied using linear sweep voltammetry. Passivation was observed upon anodic polarization of the aluminum electrode that was caused by formation of a solid AlCl₃ layer on the surface of the aluminum electrode. The electrochemical dissolution process of aluminum can be divided into electrochemically-controlled, transition, and passivation regimes. In the electrochemically-controlled regime, the dissolution rate of aluminum increased with increasing potential. In the transition regime, the dissolution rate of aluminum decreased as the potential increased because of the formation of solid AlCl₃ caused by changes in the concentration of AlCl₄^- and Al₂Cl₇^-. After a passivation layer formed, the dissolution rate of aluminum depended on the diffusion of AlCl₄^- was independent of potential; that is, the electrochemical dissolution process entered the passivation regime. The anodic limiting current density increased with agitation, increasing temperature, and decreasing mole fraction of AlCl₃ in the ionic liquid.

Dense non-doped and 5% (molar fraction) Al³⁺-doped SnP₂O₇-SnO₂ composite ceramics were prepared by reacting non-doped and 5% Al³⁺-doped SnO₂ porous substrates, respectively, with 85% H₃PO₄ solution at 600℃. The composite ceramics were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). Their conductivities in the intermediate temperature range of 100-250℃ in wet air and wet H₂ atmospheres were measured by electrochemical impedance spectroscopy (EIS). The conductivities of the 5% Al³⁺-doped SnP₂O₇-SnO₂ composite ceramic were higher than the conductivities of the non-doped SnP₂O₇-SnO₂ composite ceramic and reached 4.30×10^-2 S·cm^-1 in wet air and 6.25×10^-2 S·cm^-1 in wet H₂ at 250℃. These values are higher than those of the SnP₂O₇-SnO₂ based composite ceramic and SnP₂O₇-based ceramics under similar conditions. An H₂/air fuel cell containing the 5% Al³⁺-doped SnP₂O₇-SnO₂ composite ceramic as an electrolyte (thickness: 1.45 mm) and porous platinum as electrodes exhibited satisfactory cell performance. The maximum output power densities of this cell were 52.0 mW·cm^-2 at 175℃, 61.9 mW·cm^-2 at 200℃ and 82.3 mW·cm^-2 at 250℃. Such od performance is related to the high conductivity and sufficient density of the composite ceramic electrolyte as well as the low interfacial polarization resistance of the cell.

Pt/C, Pt-Ir/C, Pt-SnO₂/C, and Pt-Ir-SnO₂/C anode electrocatalysts were prepared by an improved Bo? nnemann method. The crystal structure, surface morphology, particle size, and surface electronic structure were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). XRD and TEM revealed that Pt nanoparticles had a face-centered cubic structure, and that dispersions were relatively homogeneous with particle sizes of 2-4 nm. Electrocatalytic activities were characterized using linear sweep voltammetry (LSV), cyclic voltammetry (CV), and amperometric (j-t) curve techniques. Catalytic performance improved with increasing temperature, and catalytic activity of Pt-Ir-SnO₂/C was optimal under these conditions. Arrhenius formula calculations showed that the synergy between Ir and Sn reduced the activation energy of Pt-Ir-SnO₂/C catalysts for the oxidation of ethanol.

Carbon aerogels have received much recent attention as high-capacity insertion anodes for rechargeable lithium ion batteries. Carbon aerogels were synthesized from resorcinol-formaldehyde with a sodium carbonate catalyst via a sol-gel process, ambient drying, carbonization, and activation. Gaseous CO₂-activated carbon aerogels combined the advantages of amorphous and nanoporous structures, with richer porous structures and more lithium insertion points than conventional carbon aerogels. Microporosity analysis indicated a high surface area, and the pore volume effectively retained lithium and its compounds. The mesoporosity allowed the mass transport of Li+ and conferred high ionic conductivity to the electrode. These improvements led to a higher lithium insertion capacity, and the activated carbon aerogel exhibited a specific surface area of 2032 m²·g^-1. X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed an amorphous structure and nanoparticle network skeleton, respectively. Lithium insertion capacities of 3870 and 352 mAh·g^-1 were exhibited in the 1st and 50th galvanostatic discharge-charge (50 mA·g^-1) cycles, respectively. This corresponded to irreversible capacities of 658 and 333 mAh·g^-1, respectively. This work demonstrates the feasibility of CO₂ activation for improving lithium insertion performance in carbon aerogels, and provides preparation and optimization procedures for other porous electrode materials.

The reductive dechlorination mechanism of benzenyltrichloride at an Ag cathode was investigated using cyclic voltammetry (CV) and potentiostatic electrolysis, in CH₃CN solvent containing 0.1 mol·L^- tetrabutylammonium perchlorate (TBAP). The adsorption of Cl^- generated during dechlorination was detected using wide anode region CV, based on its anodic reaction with Ag. The CV results indicated that: (1) Ag exhibited better electrocatalytic activity than Hg for the dechlorination; (2) the first reduction peak, which was divided from the reduction peak of benzenyltrichloride at -1.19 V (vs Ag/Ag⁺) when the scan rate was ≤50 mV·s^-1, is an adsorption controlled process and its electron transfer occurred in a concerted way, and the electron transfer coefficient is approximately 0.25; (3) the potential region where departing Cladsorbed on Ag ranged from -0.75 to -1.75 V (vs Ag/Ag⁺ ). The electrolysis results indicated that dechlorination product selectivity was strongly dependent on the Ag electrode potential.

Spinel-type NiCo₂O₄ powders were prepared by a sol-gel method, and Ni/NiCo₂O₄ electrode was prepared through composite sol method combined with sintering. The composition and structure of Ni/ NiCo₂O₄ were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energydispersive X-ray spectroscopy (EDS). Electrocatalytic properties of the Ni/NiCo₂O₄ electrode in the oxygen evolution reaction (OER) were studied in 5 mol·L^-1 KOH solution, using cyclic voltammertry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), chronoamperometry, and extended duration constant potential electrolysis. The Ni/NiCo₂O₄ electrode exhibited a lower OER overpotential, higher specific surface area, and better stability than a porous Ni electrode. The specific surface area of the Ni/NiCo₂O₄ electrode was 28.69 times greater than that of the porous Ni electrode, and its apparent activation energies decrease 166.78 and 162.15 kJ·mol^-1 at different overpotentials, respectively.

Carbon nanotubes were non-covalently functionalized by poly(diallyldimethylammonium chloride) (PDDA). Here, PDDA has three roles: reductant for the metal precursor of PtCl₆^2-, stabilizer for in-situ produced Pt nanoparticles (Pt NPs), and anti-corrosion film for carbon nanotubes (CNTs). Surface-functionalization of CNTs with PDDA was characterized by Fourier transform infrared (FTIR) spectrometry, thermogravimetric analysis, and Raman spectroscopy. The results indicated that the surface of CNTs was successfully coated with PDDA film by π-π stacking interactions, and the functionalization process had no detrimental effect on the structure of the CNTs. The obtained catalyst (Pt NPs/ CNTs-PDDA) was characterized by transmission electron microscopy, and the results showed that Pt NPs with an average diameter of ca 2 nm were highly dispersed on the surface of CNTs-PDDA. The electrocatalytic properties of Pt NPs/CNTs-PDDA nanohybrids for methanol oxidation were further characterized by cyclic voltammetry and chronoamperometry. Compared with Pt NPs supported on the pristine CNTs, the Pt NPs/CNTs-PDDA catalyst had higher electrochemical surface area and specific mass activity, and better stability towards methanol electro-oxidation.

An electrochromic (EC) material consisting of triphenylamine (TPA) core and peripheral bithiophene groups was synthesized, and the corresponding polymer was prepared by electrochemical oxidative cross-linking. The electrochemical properties of the 4,4',4?-tris[4-(2-bithienyl)phenyl]amine (TBTPA) monomer, and spectroelectrochemical and electrochromic properties of the poly(4,4',4?-tris [4-(2-bithienyl)phenyl]amine) (PTBTPA) polymer, were also systematically investigated. TBTPA possessing two thiophene groups exhibited better redox reversibility than that of the reported tris[4-(2-thienyl)phenyl] amine (TTPA). During electropolymerization, PTBTBA exhibited excellent film-forming property and strong adhesion to the ITO electrode, satisfying the basic requirements for achieving high EC performance. PTBTPA exhibited three different colors under various potentials (darkorange, olivegreen and dimgray). PTBTPA indicated enhanced EC performances and a higher contrast ratio of 44.7% compared with that of reported poly(tris[4-(2-thienyl)phenyl]amine) (PTTPA). PTBTPA also exhibited a higher optical contrast (ΔT) of 49% and 52% at 720 and 1100 nm, respectively. It showed fast switching responses of 0.93 and 0.91 s at 720 and 1100 nm, respectively, and higher coloration efficiencies of 198 and 285 cm²·C^-1 at 720 and 1100 nm, respectively. Scanning electron microscopy (SEM) revealed that the PTBTPA film surface had accumulated clusters of globules, which were smaller than those of PTTPA. The superior performances of PTBTPA suggested its potential as an efficient EC material.

The corrosion behavior of X70 pipeline steel in the turbulent zone was investigated in situ with a micro-electrode technique using loop jet impingement under high temperature and high pressure CO₂ environment. The morphology of the corrosion product formed on the surface and corrosion behavior of X70 steel after different periods were investigated by scanning electron microscopy and in situ electrochemical methods, respectively. The electrochemical behavior of X70 steel was closely related to the evolution of corrosion scales on the steel surface. The surface of the steel changed gradually from the presence of both substrate and corrosion product to loose, porous corrosion scales during the first 12 h. After 12 h, the corrosion scales were mainly composed of inner and outer scales. Because of the effect of high wall shear stress in the turbulent zone, the porous, less-protective outer scale was thinned and then removed from the steel surface. Consequently, the surface was increasingly covered by the compact inner scale, which decreases the corrosion rate of the steel considerably. Correspondingly, during the first 12 h, the corrosion potential E_corr and linear polarization resistance R_p of the sample decreased continuously. Meanwhile, electrochemical impedance spectroscopy (EIS) exhibited high- and medium-frequency capacitive loops and a low-frequency inductive loop. Analysis of EIS revealed that the resistance R_f of the corrosion film increased slowly and charge transfer resistance R_t decreased steadily, while the double-layer capacitance C_dl and corrosion film capacitance C_f decreased rapidly. After 12 h, the protectiveness of the corrosion scales improved with time, and thus the E_corr and R_p increased. As the inductive component weakened with time and finally disappeared at 48 h, EIS changed to double capacitive loops. The R_f, Rr, and C_dl increased quickly. Furthermore, the C_f stabilized.

To solve the issue of comparatively low operation voltage of electrochemical capacitors, a hybrid capacitor consisting of the anode electrode of tantalum electrolytic capacitor and the cathode electrode of polyaniline (PANI)/TiO₂ with high energy density and high working voltage was developed. The PANI/TiO₂ composite electrode for use as the capacitor cathode was prepared by in situ electrochemical polymerization of aniline in porous anodic titania nanotube arrays on titanium foil substrates. The composite electrode showed od rate capability with a specific capacitance of 10.0 mF·cm^-2 and a high power density of 0.55 mW·cm^-2. Using a dielectric coated anode electrode, the single-cell hybrid capacitor could withstand working voltages as high as 100 V. As the PANI/TiO₂ composite cathode only requires a small volume because of its high specific capacitance, available space can be used to enlarge the anode electrode, leading to an increase in specific capacitance of the hybrid capacitor. The hybrid capacitor had high volumetric and gravimetric energy densities, which were about four times and three times higher than those of a tantalum electrolytic capacitor. The short circuit charge-discharge cycle test for the hybrid capacitor at 100 V showed that its capacitance did not decrease, and the equivalent series resistance did not increase after 10000 cycles, indicating excellent cycle stability and power performance. The peak power density was estimated to be 847.5 W·g^-1. In addition, electrochemical impedance spectroscopy data indicated that the hybrid capacitor had od impedance and frequency characteristics.

In₂O₃-sensitized ZnO nanorod array films were prepared in a two-step aqueous process on fluorine-doped tin oxide (FTO) substrates. Field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), field-induced surface photovoltage (FISPV), and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) were used to characterize films. The influence of In₂O₃ content on the transfer characteristics of photoinduced charge carriers is discussed based on photovoltage response. The photoelectrocatalytic degradation efficiency of In₂O₃-sensitized ZnO nanorod array films was monitored using UV-Vis spectrometer. The photoelectrocatalytic activity of ZnO nanorod array and In₂O₃-sensitized ZnO nanorod array were evaluated from the degradation efficiency of rhodamine B (RhB). The effect of the In₂O₃-sensitized ZnO heterostructure on photoinduced electrons was investigated using the electrochemical workstation and the relationship between the photoinduced electron behavior and the photoelectrocatalytic process. Aqueous RhB was more efficiently degraded by the In₂O₃-sensitized ZnO nanorod array (visible light, applied bias voltage, 2 h), and the efficiency of the In₂O₃-sensitized array (95%) was 1.4 times higher than that of pure ZnO.

The anionic biomacromolecule, hyaluronic acid (HA), and cationic monomer, 2-(dimethylamino) ethyl methacrylate (DM), were used to construct an opposing charge polymer/monomer complex. Positively charged poly[2-(dimethylamino)ethyl methacrylate] (PDM) was prepared when DM monomers polymerized in aqueous solution. Self-assembly between PDM and HA was driven by electrostatic interaction, and HA/PDM complex colloid particles were formed in the aqueous medium. The HA/PDM complex structure was characterized by Fourier transform-infrared (FTIR) spectroscopy. The self-assembly behavior between HA and PDM, and the influence of polymerization time on HA/PDM complex colloid particle size, were investigated by dynamic laser scattering (DLS). Morphologies of the colloid particles were characterized by transmission electron microscopy (TEM). The influence of pH on the size and zeta potential of the colloid particles was investigated, and the emulsification of the colloid particles was preliminarily explored. The results showed that no HA/DM complex aggregates were formed before the polymerization of DM monomers. Spherical HA/PDM particles were spontaneously formed through electrostatic interaction between HA and PDM, coinciding with the gradual polymerization of DM. Particle sizes gradually decreased and stabilized with increasing polymerization time. The HA/PDM particles were pH sensitive and possessed improved emulsification properties compared with uncomplexed HA and PDM.

Hierarchical M /silicalite-1 composites were synthesized via hydrothermal treatment of M -supported porous silica using tetrapropylammonium hydroxide (TPAOH) as a template. M species were introduced into porous silica via solid-state grinding and subsequent calcination. X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) results indicated that M was uniformly distributed in the zeolite crystals. The hydrothermal stability of M / silicalite-1 before and after acid washing was detected by treatment at 800℃ in 100% steam for 10 h. The introduction of M increased the hydrothermal stability of M /silicalite-1 samples. Furthermore, acid washing could remove M impurities, increasing the relative crystallinity of samples compared with that of calcined M /silicalite-1 and introducing mesopore into zeolite simultaneously. N₂ adsorption-desorption measurements indicated that mesopores were generated in the zeolite crystals by the removal of M species. The improved hydrothermal stability and the generation of mesopores in these M /silicalite-1 samples play important roles in preserving zeolite structure, enhancing coke tolerance, slowing deactivation, and extending catalyst life during high-temperature reaction.

Hydrogen is a clean energy with high heat value that has been widely used in industry. Previous studies indicate that biomass can be converted in to gaseous fuels (hydrogen), liquid fuels and other chemicals. Biomass is the only renewable carbon resource and has attracted increasing attention because of the increasing price of oil and its environmental friendliness. To decrease energy consumption and minimize cost, it is very important to develop a process to produce hydrogen from bio-oil by low temperature steam reforming over non-noble metal catalysts. This work reports a carbon nanofiberssupported Ni (Ni/CNFs) catalyst prepared by the homogeneous impregnation method. The Ni/CNFs catalyst was successfully used to produce hydrogen via low-temperature (350-550℃) steam reforming of bio-oil. The effects of temperature and water steam/carbon molar ratio (n_S/n_C) on the reforming of bio-oil were investigated. The highest carbon conversion and H₂ yield over the 22% Ni/CNFs catalyst reached about 94.7% and 92.1%, respectively, at a reforming temperature of 550℃. The Ni/CNFs catalyst containing a uniform Ni distribution exhibited a much higher activity in low-temperature reforming of bio-oil at 350-450℃ than the usual Ni/Al₂O₃ catalyst. Reaction conditions were investigated and catalysts were characterized to reveal the relationship between catalyst structure and performance for hydrogen production from bio-oil.

A series of catalytic composite oxides (CeO₂)_x(La-Al₂O₃)_1-x (with mass fractions x=0.00, 0.25, 0.50, 0.75, 1.00) was prepared using a co-precipitation method. Thermogravimetric-differential thermal analysis (TG-DTA) was used to determine the performances of these composite oxides in the catalytic oxidation of the soluble organic fraction (SOF) of diesel exhaust. The results show that the catalyst with the highest activity, i.e., x=0.75, enabled the SOF to light-off at 125℃ and completely converted the SOF at 355℃. The catalysts were characterized using low-temperature N2 absorption-desorption, oxygen-storage capacity (OSC) measurements, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and H₂ temperature-programmed reduction(H₂-TPR). The results indicate that co-doping appropriate amounts of La and Al into the catalyst increases the specific surface area of the cerium oxide and the proportion of Ce³⁺ in the catalyst. This may improve the catalyst's adsorption abilities at low temperature and its OSC, enhancing its activity in SOF oxidation. These (CeO₂)_0.75(La-Al₂O₃)_0.25 composite oxides are promising catalysts for diesel oxidation.

A series of Pt/TiO₂ catalysts were prepared using a deposition-precipitation method and calcined at different temperatures to obtain various Pt particle sizes. The catalysts were tested for catalytic CO oxidation and the kinetics of the reaction was studied. The results showed that the Pt particle size increased with calcination temperature, and that their reactivity for CO oxidation first increased and then decreased with increasing calcination temperature, with the catalyst calcined at 400℃ possessing the highest reactivity. The kinetic investigation revealed that the reaction rate could be described by r=5.4×10^-7p _CO^0.17p_O2^0.36, suggesting that the reaction followed a Langmuir-Hinshelwood mechanism. Meanwhile, O₂ chemisorption and infrared (IR) spectroscopy of CO chemisorption on the catalysts were conducted to reveal the relationship between the catalyst structure and its catalytic behavior. It was found that the amount of O₂ chemisorption and the intensity of CO chemisorption by IR on the catalysts first increased and then decreased with increasing calcination temperature, which was consistent with the catalytic results and the kinetic equation. This could explain the catalytic behaviors of the catalysts. For example, the highest amounts of chemisorbed O₂ and CO were obtained over the Pt/TiO₂ calcined at 400℃, which resulted in the highest reactivity. Such an enhancement in reactivity was probably due to the strong interaction between Pt and TiO₂ induced by the calcination process.

C_nH_2n+1OH (n=2, 3, 5, 6) primary alcohol activation, hydrogenation and its additional effects on the performance of the Fischer-Tropsch (FT) synthesis over a cobalt catalyst were investigated in a fixed bed micro-reactor. All products were analyzed using an on-line gas chromatography. The diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) was used to investigate intermediates on the catalyst surface. In the presence of ar n or hydrogen, C_nH_2n+1OH underwent two main reactions: direct de-carbonylation to produce (CH₂)_n-1 hydrocarbons, and dehydration to produce (CH₂)_n hydrocarbons. The addition of lower carbon number alcohol (ethanol or 1-propanol) into the FT synthesis reaction had no significant effect on the hydrocarbon product distribution. While co-feeding higher carbon number alcohol (1-pentanol or 1-hexanol) into the FT synthesis reaction, the selectivity to hydrocarbons with carbon numbers greater than or equal to n-1 increased markedly because of the additive?s chain initiation on the catalyst surface.

Nanosized HZSM-5 (n(SiO₂)/n(Al₂O₃)=26) samples were hydrothermally treated with and without subsequent HNO₃ leaching. The performance of the samples for the alkylation of biphenyl (BP) with methanol to 4-methylbiphenyl (4-MBP) under fixed-bed down-flow conditions was investigated. Characterization was conducted by the adsorption of pyridine using Fourier transform infrared (FTIR) spectroscopy and thermogravimetric (TG) analysis. The effect of water on the catalytic performance of modified HZSM-5 was investigated. Both hydrothermal and combined hydrothermal-HNO₃ treatments improved catalytic stability, with the latter exhibiting better stability. Without the addition of water, BP conversion behavior resembled an open down parabolic vs reaction time over modified HZSM-5. However, this change disappeared upon the addition of water to the reaction system. Both catalytic stability and selectivity of 4-MBP were improved upon the addition of water. BP conversion after 30 h on stream was 8.6%, and the selectivity of 4-MBP was as high as about 60%. Elevating the reaction temperature to 500℃ in the presence of water led to increased BP conversion with time on stream up to 30 h, and the selectivity was stable at ~58%. The activity and stability of HZSM-5 were improved, and para selectivity was enhanced with the addition of water.

The hydroxylation of proline is a post-translational modification common in α-conotoxin and other conotoxin families. The 4-hydroxyl group of hydroxyproline adopts a trans conformation in native conotoxin, and this residue plays a key role in toxin structure and bioactivity. Little is known about the effects of the cis conformation of 4-hydroxyproline on conotoxin folding and bioactivity. The solution structures of three chemically modified α-conotoxin species containing cis- and trans-4-hydroxyproline were investigated using two-dimensional nuclear magnetic resonance (2D NMR). The selected α4/ 7-conopeptides included [γ15E]Sr1B, [O7O'/γ15E]Sr1B, and [O6O'/γ14E]Vc1A. The impact of modifying prolines cis/trans-4-hydroxyl group on the conopeptide structure was remarkable. Changing from trans- to cis-4-hydroxyproline led to notable solution conformational changes in α-conopeptide species. These included secondary structure elements, side chain orientations of key residues, and hydrogen-bonding properties. [O7O'/γ15E]Sr1B exhibited a twisted ω structure unlike that of typical α-conotoxin species. [O6O'/γ14E]Vc1A lost the turn structure around the N-/C-termini, which differed from that of Vc1.1. This study aids our understanding of the chemical modification of conotoxin, and is useful in elucidating the structure- bioactivity relationships of α-conotoxin species.

Novel Fe₃O₄-CdSe nanocomposites were prepared by depositing semiconductor on monodisperse magnetic nanoparticles. First, monodisperse Fe₃O₄ nanoparticles were fabricated by a solvothermal process in which iron acetylacetonate (Fe(acac)₃) was used as precursor, phenyl ether as reaction medium, oleic acid as surfactant and oleylamine (OAm) as both surfactant and reducing agent. Novel Fe₃O₄-CdSe heterostructures were prepared using 1-octadecene as high boiling solvent, cadmium oxide as Cd precursor, trioctyl phosphate (TOP)-Se as Se precursor, n-hexadecylamine (HDA) as surfactant, and stearic acid (SA) as growth promoter and nucleating agent. The structure and properties of the Fe₃O₄-CdSe nanocomposite were fully characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectrometry, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), UV-Vis spectrum, and photoluminescence (PL). CdSe nanoparticles were successfully attached to the surface of Fe₃O₄ and grew along the c-axis to form novel jujube pit-liked and nail-liked heterostructures with a width of 3.6 nm and length of 14.5 and 32.5 nm, respectively. The novel nanocomposites were a combination of magnetite Fe₃O₄ and hexa nal CdSe rods, and exhibited strong fluorescent emission without obvious quenching and excellent superparamagnetic properties. Fluorescent absorption shifts to longer wavelength as the length of the CdSe rods increases. The saturation magnetization of Fe₃O₄ nanoparticles, jujube pit liked and nail liked Fe₃O₄-CdSe nanocomposites were 57.80, 40.76, and 31.10 emu·g^-1, respectively.

Ce_0.65Zr_0.35O₂(CZ)mixed oxides were prepared by coprecipitation. The influence of ethanol on the performance of CZ and Pd based three-way catalysts was investigated. Samples were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen sorption, oxygen storage capacity (OSC), and hydrogen temperature-programmed reduction (H₂-TPR) techniques. The precipitation aging method had an appreciable impact on oxide structure and catalyst performance. Samples aged in ethanol-water system exhibited wide pore-size distributions, large pore volumes and high redox properties, OSC and thermal stabilities. After calcination at 1000 ° C, the specific surface area and OSC of the samples were 29.3 m²·g^-1 and 520 μmol·g^-1, respectively. The excellent structural and textural properties resulted in a high catalytic activity, wide air-to-fuel operating range, and low light-off and full-conversion temperatures to C₃H₈, CO, and NO of the corresponding three-way catalyst.

Ordered porous films were prepared by the breath figure method based on self-synthetic polystyrene-b-polyacrylonitrile (PS-b-PAN). Their morphologies were characterized by scanning electron microscopy. The influence of polymer concentration, solvent, and polymer structure on the structures of porous films was investigated. Film surfaces were covered with round hexa nally packed pores, and a honeycomb structure resided under film surfaces. With increasing polymer concentration in the chloroform (CHCl₃) solvent, pore spacing increased and the size of honeycomb structure decreased. Multilayer structures were observed at higher concentration. When better volatile carbon disulfide (CS₂) was instead used as the solvent, even highly ordered porous films were produced. Pore diameter and pore spacing increased, and the size of the honeycomb structure decreased. When the polystyrene macro-initiator (PS-Cl) without PAN blocks was adopted as the film material, nest-like structures instead of pores were formed on the film surface. The halo on the film surface suggests that when water droplets were positioned under the liquid film, defects formed on the film surface.

The synthesis, characterization, photophysical and electrophosphorescent properties of iridium(III) complex [(ppz)₂Ir(piq)] (ppz=1-phenylpyrazole, piq=1-phenylisoquinoline) are reported. The structure was defined by proton nuclear magnetic resonance (¹H NMR). The photophysical properties and energy-level structure of [(ppz)₂Ir(piq)] are studied by ultraviolet-visble (UV-Vis) absorption, fluorescence, and phosphorescent spectroscopies at 77 K, cyclic voltammetry (CV), and time-dependent density functional theory (TD-DFT) calculation. The electroluminescent properties of [(ppz)₂Ir(piq)] using 4,4'-bis(9-carbazolyl)-1, 1'-biphenyl (CBP) as a host are investigated. Absorption bands of [(ppz)₂Ir(piq)] are located at about 296, 342, 395, and 442 nm. [(ppz)₂Ir(piq)] exhibits red phosphorescent emission with a peak at 618 nm in CH₂Cl₂ solution at room temperature and 598 nm in 2-methyltetrahydrofuran (2-MeTHF) at 77 K, from which its triplet state energy (E_T) is estimated to be 2.07 eV. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) levels of [(ppz)₂Ir(piq)] are -5.92 and -3.62 eV, respectively. A theoretical calculation reveals that the HOMO of [(ppz)₂Ir(piq)] is mainly distributed on ppz and the iridium ion, while the LUMO is mainly centered on piq. Organic light-emitting diodes (OLEDs) containing [(ppz)₂ Ir(piq)]- doped CBP emitting layer exhibit an electroluminescence (EL) maximum at 616 nm, an optimized doping concentration of 8%-12% (w), maximum current efficiency of about 10 cd·A^-1, maximum power efficiency of 4.44 lm·W^-1, and International Commission on Illumination (CIE) coordinates of (0.65, 0.35). This investigation provides an important experimental basis for the application of [(ppz)₂Ir(piq)] in organic electroluminescent devices.