Atmospheric- pressure microplasma is an attractive gaseous electrode, and may replace the commonly used rare metal electrodes for electrochemical reactions. The reactions at the plasma anode-liquid interface have not been well investigated, and application of plasma anodes to electrodeposition is still rare. In this communication, by choosing the oxidation of ferrocyanide to ferricyanide as a model reaction, we carefully investigated the charge-transfer reaction at the interface between a plasma anode and an ionic solution. The results showed that ferrocyanide was progressively oxidated to ferricyanide over time, and the rate of oxidation was proportional to the discharge current. We also found that after the discharge the oxidation percent of ferrocyanide still increased approximately linearly with storage time, and the increasing rate was dependent on the discharge time. The rate of oxidation after discharge was much lower than that caused by discharge. These results demonstrate that atmospheric-pressure microplasma could act as a gaseous anode for transferring positive charges at the plasma-liquid interface and inducing electrochemical reactions in solution. During discharge, oxidative active species were also produced. We also successfully electrodeposited copper on stainless steel with the assistance of a microplasma anode in CuSO4 saturated solution, and the current efficiency was about 90%.

Underpotential deposition (upd) has been a hotspot in the field of electrochemical research throughout the years owing to its significant theoretical and applied research value. Theoretical research on upd primarily centers around the relations and rules of interaction among deposition substrates, deposition species, and anions (or other organic additives) during upd process. In this paper, the developments in theoretical research in recent years on upd on both the local and international levels are systematically summarized mainly from two viewpoints, namely, thermodynamics and kinetics. With regard to the thermodynamics of upd process, introductory comments and mathematical formulas are summarized from four aspects, i.e., underpotential shift (ΔE_upd), electrosorption valency (γ), influence of temperature, and electrochemical adsorption isotherms. The applications and analyses of those related mathematical formulas are also presented in detail. In terms of the kinetics of upd process, nucleation and growth phenomena are mainly presented. We summarize the relevant mathematical models, and additionally introduce research studies on the characteristics of upd kinetics based on these mathematical models. Furthermore, this paper presents an outline of computational chemistry methods and application achievements concerning upd research. Finally, the theoretical research status of upd is presented, giving an overall view of the development trend.

A variety of primary in situ research techniques applied to underpotential deposition (upd) research, including electrochemical (cyclic voltammetry (CV), chronoamperometry (CHR), and electrochemical impedance spectroscopy (EIS)), interfacial (electrochemical quartz crystal microbalance (EQCM) and electrochemical scanning tunneling microscopy/electrochemical atomic force microscopy (ECSTM/ECAFM)) and X-ray based (X-ray absorption spectroscopy (XAS) and surface X-ray scattering (SXS)) analysis techniques, are summarized in this paper. We summarize and discuss the upd characteristics of many electrochemical systems as determined by these research techniques, and analyze the corresponding relationships and principles between the upd microscopic characteristics and macroscopic test results. Some conclusions of vital importance to upd drawn based on these techniques are explicitly discussed. Also, the merits and demerits of the above-mentioned research techniques are presented and compared. In the matter of application research areas of upd, four main aspects are summarized and analyzed: function materials' electrosynthesis, electroanalysis, electrochemical atomic layer epitaxy (ECALE), and electrochemically active surface area (ECSA) characterization of noble metal (or nano) materials. Meanwhile, the principles involved in the aforementioned applications research related to upd process are briefly explained. Finally, with respect to both research techniques and application research, this paper reveals the current status of upd research and gives a bird's eye view of development trends.

A new smog chamber with dual reactors was designed and constructed to study atmospheric oxidation processes that may form ozone or secondary organic aerosols (SOAs). The chamber consists of two 5 m³ fluorinated ethylene propylene (FEP) Teflon-film reactors housed in a thermally isolated enclosure, in which the temperature can be well controlled in the range of -10 to 40 ℃. The influence of the light source on the gasphase oxidation mechanism of propene was investigated. The results showed that multiple ultraviolet (UV) light sources were better than traditional narrow-band black-lamp light sources. Preliminary experiments on propene and m-xylene photo-oxidation processes were performed. The results showed that the dual-reactor chamber can simulate the gas-phase oxidation processes that form ozone or SOAs, and can be used to determine the effects of various species by comparing experiments performed using different initial concentrations. The SOA yield data from m-xylene photo-oxidation under different NO_x conditions were in od agreement with those from previous studies. This proves that the chamber can simulate gas-to-particle conversion processes. The dual reactors have the advantage of enabling experiments to be performed with only one key parameter being changed. This will help us to further understand the role of key factors in complex atmospheric pollution processes.

The thermotropic phase-transition compounds 1-alkylammonium tetrachlorocobaltate (1-C_nH_2n+1NH₃)₂CoCl₄ (n=10, 18) and a series of their binary mixtures were prepared by solution reflux at 353 K in ethanol solutions. Binary-mixture (1-C₁₀H₂₁NH₃)₂CoCl₄-(1-C₁₈H₃₇NH₃)₂CoCl₄ systems were characterized over the entire composition range using differential scanning calorimetry and X-ray diffraction. The phase diagram constructed from the experiments indicated one stable intermediate phase, (1-C₁₀H₂₁NH₃)-(1-C₁₈H₃₇NH₃)CoCl₄, at a mass fraction w_C10Co=52.51%, two invariant three-phase equilibria, and two eutectoid temperatures, which are assigned to e1 at (347±1) K, for the eutectoid point with w_C10Co=38.50%, and e2 at (343±1) K, for the eutectoid point with w_C10Co=69.86%. These three clear solid-solution ranges are α-phase on the left, β-phase on the right, and γ-phase in the middle of the phase diagram. The (1-C_nH_2n+1NH₃)₂CoCl₄ and their binary-mixture systems as phase change materials have phase-transition temperatures in the range 340-370 K, and transition enthalpies in the range 2.13 and 141.12 J·g^-1, between two polymorphic crystal forms.

A new reduced chemical kinetic model that includes 103 species and 199 reactions is developed and used to describe the oxidation of a gasoline surrogate fuel consisting of n-heptane, iso-octane, toluene, and diisobutylene (DIB) for homogeneous charge compression ignition (HCCI). DIB is mainly consumed by Habstraction reactions by OH radicals to form three isomers, namely JC₈H₁₅- A, JC₈H₁₅- B, and JC₈H₁₅- D. Decomposition reaction is also one of the main reactions of DIB consumption, and this process forms two important C₄ products, namely TC₄H₉ and IC₄H₇. These products are the primary sources for CH₂O generation. The skeletal mechanism of toluene reference fuel (TRF) is based on the existing semi-detailed TRF mechanism developed by Andrae. The toluene and DIB sub-mechanism is developed using reaction path and sensitivity analyses. od agreements are achieved with the experimental ignition delays observed in a shock tube and an HCCI engine. The present reduced model has reliable performance for HCCI combustion simulations.

In this work, we examined the structural and ―OH stretching vibrational dynamics of ethylene glycol (EG) solvated in acetonitrile (MeCN), acetone (AC), tetrahydrofuran (THF), and dimethylsulfoxide (DMSO) using steady-state linear infrared (IR) spectroscopy and ultrafast pump-probe IR spectroscopy. The results suggested that the frequency position, bandwidth, and vibrational relaxation of the ―OH stretching vibration that participate in the formation of intermolecular hydrogen bonds (IHBs) were strongly influenced by the type of solvent. At least two types of IHBs were detected in the EG solution including clustered solute-solute IHBs and solute-solvent IHBs. Quantum chemical calculations predicted a similar solvent dependence of the ―OH stretching vibrational frequency to that observed in the IR experiments. Furthermore, we found that the IHB-involved ―OH stretching mode in the case of solute-solvent clusters displayed the slowest population relaxation dynamics in the case of EG in MeCN. The relaxation became slightly faster in AC and even faster in THF. The fastest dynamics was observed in the case of EG in DMSO. However, in each solvent environment examined, the IHB-involved ―OH stretching mode in the solute-solute cluster displayed the fastest population relaxation. The results obtained in this study provide further insights into different IHB structural dynamics in co-existing solute-solute and solutesolvent clusters.

We report a comparative study on the characterization of three trivalent uranium complexes using 12 density functional theory (DFT) methods, i.e., BP86, PBE, B3LYP, B3PW91, BHandHLYP, PBE0, X3LYP, CAM-B3LYP, TPSS, M06L, M06, and M06-2X, representing (meta-)GGA and hybrid (meta-)GGA levels of treatment of molecular systems. The MP2 method was used in single-point calculations to provide an ab initio view of the electronic structure. Three model systems in the experimental work on the activation of CO₂ and CS₂ by a trivalent uranium complex (Tp^*)₂U-η¹-CH₂Ph (Cpd2) were used i.e., (Tp^*)₂U-η¹-CH₂Ph (Cpd2), (Tp^*)₂U-κ²- O₂CCH₂Ph (Cpd3), and (Tp^*)₂U-κ²-S₂CCH₂Ph (Cpd4) (Tp=hydrotris(3, 5-dimethylpyrazolyl)borate). The hybrid functionals, B3LYP and B3PW91, displayed od performance in view of both the geometrical and electronic structures. The MP2 method generated consistent results as DFT methods for Cpd2 and Cpd3, while provided an odd picture of the electronic structure of Cpd4 that may be due to its single determinant feature, leading to its capture of an electronic configuration of Cpd4 different from the one with the DFT methods. The use of a quasi-relativistic 5f-in-core ECP (LPP) treatment for U(III) in the thermodynamic calculations was supported by the calculations with a small-core ECP treatment (SPP) for U. Owing to increasing interests in low-valent actinide molecular systems, this work complements previous comparative studies, which mainly focus on highvalent actinide complexes, and provides timely information on the performance of 12 widely used DFT methods in studying low-valent actinide systems. It is expected to contribute to a more sensible selection of DFT methods in the study of low-valent actinide molecular systems.

Using the pseudo-potential plane-wave based on the density functional theory (DFT), the electronic structures and optical properties of intrinsic ZnO, Y-, Cu-, and Y-Cu co-doped ZnO were studied. The results show that the conductivity of ZnO can be improved by Y and Cu doping because of the increase in carrier concentration under the order of magnitude of the doping concentration in this paper. Y-Cu co-doping leads to degeneration and makes ZnO metallic. Y-doped ZnO can show enhanced light absorption in the ultraviolet region, while doping with Cu enhances absorption in the visible and near ultraviolet regions. Y-Cu co-doping greatly increases the absorption of visible and near ultraviolet regions owing to the synergistic effect between Y ions and Cu ions, which can be exploited to fabricate the opto-electronic devices.

We employed the generalized energy-based fragmentation (GEBF) approach to investigate the gas-phase structures of B-DNA double-helices up to 10 base pairs at several theoretical levels. By comparing the results obtained using the M06-2X functional and other methods (including the B3LYP, B3LYP-vdW, and TPSS functionals), we found that the absence of stacking interactions could lead to the enlargement of the vertical distance between adjacent bases. The magnitude of this enlargement of the vertical distance quickly decreases as the length of the double-helix increases. The gas-phase stabilization of the double-helical structure of B-DNA is a cooperative effect, in which hydrogen bonding plays a more important role than stacking interaction does up to 10 base pairs.

The most stable (Al₁₆Ti)^n± (n=0-3) ions were modeled and optimized using density functional theory combined with all-electron spin-polarized calculations. The geometries, stabilities, and electronic structures of the (Al₁₆Ti)n ± (n=0-3) ionic clusters, as well as the adsorption structures and adsorption energies of H₂O molecules on the (Al₁₆Ti)^n± (n=0-3) ionic clusters, were studied. The results were compared with those obtained for pure (Al₁₇Ti)^n± (n=0-3) ionic clusters. The spatial distributions of the highest occupied molecular orbitals and the lowest unoccupied molecular orbitals for the (Al₁₆Ti)^n± (n=0-3) ionic clusters showed that the free electrons tend to occupy Ti sites. And a few residual free electrons would occupy sites with large curvatures. An extensive structure search was performed to identify the low-energy conformations of (Al₁₆TiH₂O)^n± (n=0-3) complexes. Based on the geometries of the studied adsorption complexes, it was found that the most stable structures were prone to oxygen-based adsorption onto Ti atom. (Al₁₆TiH₂O)⁺ ion featured the shortest average O―H bond length, that was ~0.0003 nm longer than that observed in isolated H₂O molecule. The O―H bond length increased with either increasing or decreasing number of the electrons. The studies implied that Ti dopant in Al ionic clusters improved the dissociation efficiency of H₂O molecules. Furthermore, the doping effect played a more important role than the geometry effect in determining the electronic structures of the (Al₁₆Ti)n ionic clusters and their interaction with H₂O molecules.

The coordination structures of metal string complexes (n, m)[Cr₃(PhPyF)₄Cl₂] (HPhPyF=N, N'- phenylpyridylformamidine; n=2, 3, 4; m=2, 1, 0) with potential applications as molecular wires have been investigated using the density functional theory BP86 method by considering the effects of an external electric field (EF). Herein, n and m represent the number of benzene rings on the left and right in the PhPyF- ligand, respectively. The results show that: (1) under zero field, the three kinds of coordination modes ((2, 2), (3, 1), (4, 0)) of the four PhPyF- ligands are close in energy, which indicates that they are competitive conformations. The (2, 2) coordination mode is the most stable one. The Cl axial ligands on the two sides of (4, 0) can coordinate to Cr atoms, indicating that these two axial ligands can combine with electrodes. Moreover, the Cl₄― Cr1 bond is stronger than Cl5―Cr3, different from (4, 0) [CuCuM(npa)₄Cl] [PF₆] (M=Pd, Pt; 2- naphthyridylphenylamine) in which the axial ligand Cl close to benzene cannot coordinate to metal atom M. (2) There is a 3-center-3-electron delocalization σ bond in the Cr₃^{6 +} chain for (2, 2), (3, 1), and (4, 0), but the delocalization gradually weakens. The polarity from Cl₄ to Cl5 is stronger as the coordination mode of four PhPyF- ligands becomes more consistent. (3) The geometry and electronic structure of the investigated complexes change regularly under the electric field. Because the electron transfer direction of (3, 1) and (4, 0) is the same as its molecular polarity, the bond length, spin density, charge and energy gap are more sensitive to -Z electric field. Therefore, the -Z elelctric field is beneficial to the conductivity of the molecules. Moreover, the sensitivity of the structures to electric field increases with polarity.

Colloidal chalcopyrite CuInS₂ (CIS) quantum dots (QDs) were synthesized using copper(I) iodine (CuI) and indium(III) acetate (InAc3) as metal cationic precursors, and dodecanethiol (DDT) as the sulfur source and solvent. The microstructure and optical properties of the prepared CIS QDs were characterized by X-ray diffraction (XRD), Raman spectroscopy, high-resolution transmission electron microscopy (HRTEM), and UVVis absorption spectroscopy. The results showed that the CIS consisted of chalcopyrite phase and exhibited Cu-Au ordering. With prolonged reaction time, the grain sizes of the QDs became larger and the absorption edges of the CIS QDs showed a red-shift owing to the size-induced quantum confinement effect. For the first time, DDT-capped CIS QDs with narrow size distribution were connected to the inner surface of mesoporous TiO₂ films via a thioglycolic acid (TGA)-assisted adsorption approach, which was simple and easy to carry out. The adsorption behaviors of both TGA and the CIS QDs on the TiO₂ films were detected by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The results indicated that TGA was adsorbed onto the surface of TiO₂ via COOH groups while the ―SH group was exposed outside, and replaced DDT at the surface of the CIS QDs, leading to the attachment between TiO₂ and CIS. It was revealed that the CIS QDs of ~3.6 nm in size exhibited the best light absorption capacity and photovoltaic performance. An over-coating of CdS significantly improved the performance of the QDS

We report the synthesis of CdS polycrystalline thin films deposited with 0%, 0.88%, 1.78%, 2.58%, and 3.40% (volume fraction, φ) O₂ in sputtering Ar gas using a radio frequency magnetron sputtering method. The obtained CdS samples were characterized by X-ray diffraction, scanning electron microscope, Raman spectroscopy, ultraviolet-visible (UV-Vis) absorption spectroscopy, and X-ray photoelectron spectroscopy. O incorporation led to the formation of compact and small CdS grains. The band gap values of the CdS thin films deposited with 0.88%and 1.78% O₂ were 2.60 and 2.65 eV, respectively, and were larger than that of CdS (2.48 eV) deposited without O₂ gas in sputtering Ar gas. In contrast, the band gap values of the CdS thin films deposited with 2.58% and 3.40% O₂ (2.50 and 2.49 eV, respectively) were consistent with that of CdS (2.48 eV) deposited without O₂ gas in sputtering Ar+O₂ gas. The CdS thin film deposited with 0.88% O₂ displayed the highest crystalline quality. Subsequently, CdTe thin films were deposited by radio frequency magnetron sputtering method on the surface of the CdS thin films. The CdTe thin films were characterized before and after high-temperature anneal treatment in a CdCl₂ atmosphere. The results showed that O incorporation into CdS led to the formation of considerably more closely packed and larger CdTe grains. The synthesis of CdS with large band gap values at room temperature is facile and effective using the current method. Therefore, the method presented herein is very promising for large-scale industrial production.

Owing to its high impedance, studying atmospheric corrosion using a traditional reference electrode (RE) is difficult. To obtain more accurate information on the electrochemical processes involved in atmospheric corrosion, it is necessary to improve the traditional RE. In this paper, the corrosion behavior of copper under an electrolyte droplet containing (NH₄)₂SO₄ was investigated by electrochemical impedance spectroscopy (EIS) and polarization measurements using a three-electrode system with a modified RE. The average corrosion rate increased with decreasing electrolyte volumes (from 1 to 20 μL) and with decreasing heights of the droplet at heights below 850 μm. The EIS and polarization results were in agreement, thereby demonstrating that the modified RE could be effectively used to study atmospheric corrosion under an electrolyte droplet.

Highly pure plastic crystal, 1-ethyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (P₁₂TFSI), was synthesized and purified by an easily industrializable recrystallization method. The P₁₂TFSI/LiFSI ionic liquid was obtained by mixing P₁₂TFSI with 30% (molar fraction, x) LiFSI. Electrochemical characterization methods including cyclic voltammetry, constant voltage polarization and charge/discharge at constant current were used to investigate the electrochemical window, stability vs Al corrosion, and battery performance of the ionic liquid.Awide electrochemical window of 5.00 V, non-corrosion of theAl current collector, and 0.92mS·cm^-1 of ionic conductivity at room temperature were observed. LiCoO₂/Li batteries assembled using this ionic liquid electrolyte showed od charge-discharge characteristics and cycle performance, comparable with those of carbonate-based electrolyte at low rate. The specific capacity of the LiCoO₂ remained 175 mAh·g^-1 after 20 cycles (95.1% capacity retention) despite cycling at a high voltage up to 4.50 V. These results indicate that the plastic crystal-based ionic liquid P₁₂TFSI/LiFSI could be potentially applied in high-energy density lithium secondary batteries.

Fatty acid vesicles (FAVs) have hollow core-shell structures similar to those of liposomes, and the building block fatty acids are naturally abundant, green, and safe; therefore, FAVs have potential applications in embedding/release systems. However, FAVs are pH sensitive, and the pH window for FAV formation is narrow and biologically unsuitable. These disadvantages prevent FAVs from being used in domestic chemicals and externally applied agents. In this study, a green and safe nonionic surfactant, alkyl polyglucoside (APG), was blended with a model fatty acid conjugated linoleic acid (CLA) to help the latter to form FAVs in a biologically suitable pH window. The experimental results showed that mixing CLA with APG changed the pH window from 8.0-9.0 for CLA to 6.0-8.0 for CLA-APG; this matches the biologically suitable pH range. Methods for improving the pH dependence of FAV formation and the pH-sensitive properties of FAVs were investigated.

The self-assembly and hydrogelation of two series of lipopeptide amphiphiles, C_nV₃K₂ (n=12, 14, 16) and C_mKV₃K (m=14, 16), were studied to determine the effects of alkyl chain length and peptide charge distribution. Both the transmission electron microscopy (TEM) and atomic force microscopy (AFM) results showed that all lipopeptide molecules in both series self-assembled into nanotapes with a bilayer structure. The width of the nanotapes decreased with increasing alkyl chain lengths. At a given alkyl chain length, the width of the C_mKV₃K nanotapes was wider than that of the C_nV₃K₂ nanotapes. Based on the circular dichroism (CD) spectra of the nanotapes, all three C_nV₃K₂ molecules adopted a secondary structure of β sheet. In contrast, the secondary structure of the C_mKV₃K nanotapes comprised a mixture of α helix and β sheet. For C14KV3K, the content of the α helix structures was higher than that of the β sheet structures. Conversely, for C16KV3K, the content of the β sheet was higher than that of the α helix structures. The nanotapes of lipopeptides with long alkyl chains were narrower than those with short chains, suggesting that the increased alkyl chain hydrophobicity inhibited lateral stacking of β sheets. When compared with C_nV₃K₂, of which the two positive charges are arranged at the carbon terminal, the separate arrangement of the two positive charges in C_mKV₃K reduced electrostatic repulsion and favored lateral stacking of β sheets to produce wider nanotapes. The rheological data showed that all lipopeptides formed self-supporting hydrogels at 10 mmol·L^-1 and pH 8.4. The hydrogel strength of the lipopeptides with different alkyl chain lengths was nearly the same within a given series. Furthermore, the hydrogel strength of the lipopeptides in the C_mKV₃K series was higher than that of the lipopeptides in the C_nV₃K₂ series. The results indicated that the hydrogel rheological property was more influenced by charge arrangement at the peptide segment than by the alkyl chain length. Also, pH influenced to a great extent the self-assembly of the lipopeptides. The lipopeptides in the C_mKV₃K series were more sensitive to pH than those in the C_nV₃K₂ series.

A sequential modification by sodium hydroxide (NaOH) and ammonium hexafluorosilicate ((NH₄)₂SiF₆) solution was used for preparing MTP (methanol to propylene reaction) catalyst for the first time. The parent and modified samples were characterized by diverse techniques including powder X-ray diffraction (XRD), X-ray fluorescence (XRF) spectroscopy, N₂ adsorption-desorption, transmission electron microscopy (TEM), and NH₃ temperature-programmed desorption (NH₃-TPD). The effect of modification on the physicochemical properties, such as framework, chemical composition, texture, and acidity, were investigated in detail. The results showed that the mesopore volume of the zeolite catalyst increased significantly following sequential NaOH and (NH₄)₂SiF₆ modification. The acidity was also modulated effectively. The composite modification method successfully overcame the disadvantages associated with individual simple alkali and (NH₄)₂SiF₆ treatments. For instance, using a simple alkali treatment would destroy the framework of the zeolite easily, whereas using a simple (NH₄)₂SiF₆ treatment would only modify the external surface of the zeolite owing to the limited diffusion of the ammonium hexafluorosilicate molecule. When used in MTP reaction, the induction period of the composite modified sample was greatly shortened, and the initial selectivity for propylene increased to 43% under the following operating conditions: T=470 ℃, p=0.1 MPa (p_MeOH=50 kPa), and weight hourly space velocity (WHSV)=2 h^-1. Moreover, the composite modified zeolite catalyst exhibited significantly improved stability, and the catalytic lifespan was triple that of the parent sample.

Graphene oxide ( ) was synthesized using an improved Hummers method. Subsequently, catalysts of manganese oxides (at varying loadings) supported on graphene (MnO_x/GR) were prepared by hydrothermal reaction for application in the selective catalytic reduction (SCR) of NO_x with NH₃ at low temperatures. The structural properties and catalytic performance were evaluated by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray powder diffraction (XRD), transmission electron microscopy (TEM), N₂ adsorption-desorption, X-ray photoelectron spectroscopy (XPS), and H₂ temperature-programmed reduction (H₂-TPR). The characterization results indicated that abundant functional groups existed on the surface of the prepared that could combine with manganese during preparation of the catalysts. Manganese oxide entities, with different crystallinities (MnO, Mn₃O₄, or MnO₂), were dispersed on the surface of graphene. The results of the catalytic studies showed that the MnO_x/GR catalysts prepared with different MnO_x loadings all exhibited excellent low-temperature SCR activities. The catalyst with 20%(w) MnO_x displayed the best activity, which was attributed to the high content of high-valent manganese and oxygen adsorbed onto the catalyst surface, as well as to the enhancement in redox abilities and the addition of active sites at low temperatures.

Tin-promoted Ru/H-CMK-3 catalysts were prepared by a novel reductant-impregnation method for application in the hydrogenation of cinnamaldehyde. The catalysts were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) specific surface areas, X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The effects of the synthesis reaction conditions on the selective hydrogenation of cinnamaldehyde were examined in detail. The results showed that the mesoporous CMK-3 carbon material could disperse the catalytically active species better. Using appropriate amounts of Sn(IV) provided electron-rich Ru sites, which are one of the main catalytically active species. The interaction between Ru and Sn promoted the activation of C＝O in cinnamaldehyde. Furthermore, changes in other reaction conditions, such as temperature and pressure, greatly influenced the selective hydrogenation of cinnamaldehyde.

Sr/TiO₂ catalysts with different Sr/Ti molar ratios (n(Sr)/n(Ti)) were synthesized by fractional precipitation. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectrometry, and ultraviolet-visible diffuse reflectance spectrophotometry (UV-Vis RDS). The photocatalytic activity of the samples under visible light was determined using the photocatalytic degradation of methylene blue. The photocatalytic activities and structures of the catalysts changed with n(Sr)/n(Ti) molar ratio. When n(Sr)/n(Ti)≤3/2, the catalysts, which were composed of TiO₂ and SrTiO₃, showed a globular structure. When n(Sr)/n(Ti) was between 3/2 and 4/1, the catalysts had a flaky structure. As the n(Sr)/n(Ti) increased, the composition of the catalysts changed from SrTiO₃ and Sr₂₄ to Sr₂₄ and Sr(OH)₂·H₂O. When the n(Sr)/n(Ti) ratio was 9/1, the catalyst mainly consisted of Sr(OH)₂ ·H₂O and exhibited an acicular structure. The sample with n(Sr)/n(Ti)=4/1 exhibited the highest photocatalytic activity; its first-order reaction rate constant was 5.0 times as high as that of the perovskite catalyst SrTiO₃ and 86.7 times as high as that of the commercial Ti photocatalyst P25.

This paper presents an in-house-designed dielectric barrier discharge (DBD) plasma reformer for hydrogen production via partial oxidation reforming of methane. We examined the effects of oxygen/carbon (O/C) molar ratio, feed flow rate, discharge gap, discharge zone length, filler diameter, filler shape, filler materials, discharge voltage, and discharge frequency on the hydrogen production performance i.e., CH₄ conversion rate, H₂ yield, and selectivity of products (H₂, CO, and CO₂). The experimental results showed that the parameters of the discharge zone played an important role in the CH₄ conversion rate. For instance, CH₄ conversion rate increased with increasing discharge zone lengths. When the discharge zone length increased from 5 to 20 cm, CH₄ conversion rate increased from 6.87% to 22.26%, which corresponds to an improvement of 224%. Also, the fillers in the discharge zone strongly influenced the hydrogen production performance. Using reactors with fillers generated higher CH₄ conversion rates. Moreover, using fillers with more appropriate dielectric constants is advantageous for practical application. The H₂ yield and hydrogen selectivity increased with increasing discharge frequency. Specifically, when the discharge frequency increased from 1.5 to 7.0 kHz, H₂ yield increased from 1.10% to 9.49%, and hydrogen selectivity increased from 21.18% to 30.06%. It is believed that the current results would serve as a od guideline in hydrogen production from hydrocarbon fuels by plasma reforming.

The high-temperature thermal stability of solution-processed polymer solar cells is a key issue that determines the feasibility of further thermal encapsulation processes, such as thermal lamination or hightemperature atomic layer deposition. In this article, polymer solar cells with poly(3, 4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) or MoO₃ as the anode buffer layer (ABL) and ZnO or LiF as the cathode buffer layer (CBL) were fabricated with a device structure of indium tin oxide (ITO)/ABL/poly(3-hexylthiophene): phenyl- C₆₁- butyric acid methyl ester (P3HT:PC₆₁BM)/CBL/Al. Device performances, especially the hightemperature thermal stability of the devices, were studied in detail. The results indicated that the thermal stability of the organic solar cells was highly dependent on the buffer layer material. Devices with MoO₃ as ABL and ZnO as CBL showed high thermal stability at a temperature of 120-150 ℃, which ensures the possibility of subsequent thermal processing. In addition, the use of ZnO as the cathode buffer layer could also improve longterm device stability.

In-doped ZnO nanorods (NRs) were synthesized by hydrothermal method. The X-ray diffraction (XRD) patterns showed that the ZnO lattices expanded upon In doping. According to the scanning electron microscopy (SEM) images, the aspect ratio (length- to- width ratio) of the ZnO NRs decreased as the concentration of In(III) in the precursor solution increased from 0% to 1.0% (atomic fraction, x), and increased with further increases in the In(III) concentration from 1.0%to 5.0%. The nonlinear modulation of the aspect ratio of ZnO NRs is believed to be due to the competition between the subst itutional doping of In³⁺ (In_Zn) and formation of InOOH intermediate, both of which are closely related to the behavior of In(OH)₄^-. In(OH)₄^- can be adsorbed onto zinc polar plane, and thus inhibits adsorption of Zn(OH)₄^2- growth units. Furthermore, In(OH)₄^- can convert into InOOH, which can act as a crystal binder and enhance growth along the (002) plane. In_Zn can disrupt the zinc polar plane, resulting in the suppression of growth along the (002) facet. Therefore, the aspect ratio of ZnO NRs can be controllably modulated by changing the In concentration in the precursor solution. The current study furthers our understanding of the growth mechanism of In-doped ZnO, and presents a feasible method to prepare doped-ZnO NRs for real applications.

The effect of post-treatment HCl concentration on titanate-titania transformation was investigated. Titanate was prepared by the alkaline hydrothermal treatment of TiO₂, and then transformed to titania/titanate upon subsequent washing with 0.10-0.55 mol·L^-1 HCl. The titanate almost completely transformed to rutile when treated with HCl concentrations>0.78 mol·L^-1. Accompanying this phase transformation, the morphology of the sample changed from nanotubes to nanosheets and nanoparticles. This was related to the rate of phase transformation, which depended on the HCl concentration. Titanate became resolved into detached TiO₆ octahedra during HCl treatment, and titanate-titania transformation occurred via rearrangement of the TiO₆ octahedra. The phase transformation and morphological evolution were studied by X- ray diffraction, and transmission and scanning electron microscopies. The linear and nonlinear optical properties of the products were investigated using ultraviolet-visible absorption spectroscopy and the open aperture Z-scan technique, respectively. The minimum transmittance at Z=0 and maximum optical limiting effect were obtained when the HCl concentration was 0.55 mol·L^-1. Different nonlinear optical effects were exhibited by different morphologies.