With the rapid development of laser technology, laser weapons that can cause increasing amounts of harm to humans are emerging. In recent years, studies on optical limiting (OL) materials have been carried out with great efforts among countries. Phthalocyanine (Pc) compound exhibits characteristics of broad OL threshold, obvious limiting effect, and fast response. Because of these characteristics, Pc is considered as a very promising OLmaterial that is significant in laser protectivematerials' research, which currently focuses on increasing performance and stability. This paper reviews and summarizes the current knowledge of Pc OL materials. First, the mechanism of the OL effect of Pc compounds is introduced, and then followed by a detailed analysis of the factors influencing the OL effect and process, and the influence on the photophysical and OL performance of Pc materials. The analysis highlights problems to be solved and proposes the future direction for Pcmaterials' research.

Dye sensitization is an important strategy for broadening the excitation wavelength range of wideband- gap photocatalysts to use visible light from the sun. In this paper, the primary principle of dye-sensitized water splitting for hydrogen production was introduced, and the research progress in dye sensitizers, sensitized matrixes or supporters, the interaction between dyes and matrixes, co-catalysts for hydrogen evolution, and sacrificial electron donors were all reviewed. Moreover, the pathways of charge transmission and stability issues in dye-sensitized systems were discussed.

Mg(NH₂)₂-2LiH composite is one of the most promising high-capacity hydrogen storage materials developed in recent years. Research on Mg(NH₂)₂-2LiH material for hydrogen storage is of considerable interest because of its favorable thermodynamic properties, high reversible hydrogen capacity, relatively low operating temperatures, and od cycling stability for dehydrogenation/hydrogenation. In this review, the recent progress in the hydrogen storage properties of Mg(NH₂)₂-2LiH material was systematically summarized. The focus is on the effect of material composites, crystal structures, particle (grain) sizes, and catalysts on the hydrogen storage properties of the Mg(NH₂)₂-2LiH material, and their reaction mechanisms for hydrogen storage. The challenges in and direction for further improving the hydrogen storage properties of the Mg(NH₂)₂-2LiH material are also pointed out.

A four-component RP-3 aviation kerosene surrogate fuel, comprising 40% n-decane/42% n-dodecane/ 13%ethycyclohexane/5%p-xylene (molar fraction), was presented. Experiments showed the physical and chemical similarity of the surrogate fuel to the real RP-3. Counterflow, twin-flame experiments were used to determine the laminar flame speeds of both the real and the surrogate fuel and showed that the surrogate fuel accurately modeled the burning rate of real RP-3. A semi-detailed chemical reaction mechanism for ignition and oxidation of the RP-3 surrogate fuel that consists of 168 species and 1089 elementary reactions has been developed. Experimental results validate the model and highlight its ability to accurately predict the ignition delay times and laminar flame speeds of real RP-3.

According to a component analysis of RP- 3 aviation kerosene and eight surrogate models' comparative data, a surrogate model comprising n-dodecane/1,3,5-trimethylcyclohecane/n-propylbenzene (73.0%/14.7%/12.3%, mass fraction) was obtained. A detailed mechanism for the combustion of RP-3 surrogate fuel at high temperature was developed using an automatic generation software package, ReaxGen. Ignition delay times simulated using this mechanism were compared with experimental data. A detailed mechanism was reduced by adopting rate-of-production analysis and approximate trajectory optimization al rithm (ATOA) reduced methods. Finally, the sensitivity of ignition delay time was analyzed under conditions of different equivalent ratios and pressures using the reduced mechanism. Differences in key reactions contributing to the ignition delay time were identified at different equivalent ratios. The results indicate that our mechanisms can characterize the ignition delay time during combustion of RP-3 kerosene at high temperature.

Aseries of imidazolium salt-based ionic liquid crystals with a smectic A(SmA) phase are synthesized by altering the substituents attached to the 1-position (N1) and 3-position (N3) of the imidazolium ring, and anions. The mesogenic properties of the imidazolium salts, including mesophase temperature range and structural properties, are studied by differential scanning calorimetry, small-angle X-ray diffraction, and single crystal diffraction. The anisotropic ion conductivities of several ionic liquid crystals are also measured. It is found that substituents attached to N1 or N3 and the anions influence the van der Waals interactions and hydrogen bond, which results in a significant effect on the mesogenic properties of the imidazolium salts. Moreover, when a vinyl group is attached to the N3 position, π-π stacking interactions form between adjacent layers. This not only benefits the formation of a mesophase but also results in the biggest layer spacing and lowest anisotropic ion conductivities for imidazolium tetrafluoroborates. These results suggest that all intermolecular interactions should be taken into account when regulating the mesogenic properties of ionic liquid crystals.

The adsorption and separation behaviors of CO₂ and CH₄ binary mixture in graphene/nanotube hybrid structures (GNHSs) are investigated by grand canonical Monte Carlo (GCMC) combined with molecular dynamics (MD) simulations. CO₂ is preferentially adsorbed in the adsorbents. Compared with a (6, 6) SWCNT (single walled carbon nanotube), GNHSs show improved separation performance. As the temperature rises, the loading of CO₂ reduces rapidly while the loading of CH₄ first increases before being reduced. Finally, the kinetic parameters of CO₂ and CH₄, such as self-diffusivity and residence time, are calculated by MD simulation. The CO₂ molecules diffusing in the GNHS need to overcome a higher barrier relative to that for CH₄. The diffusion of the two components in the adsorption layer outside of adsorbent also influences the separation of the mixture.

The possibility of morphological control of iron oxide as an oxygen carrier for chemical looping combustion was investigated using density functional theory and experiment. First, we calculated the reactivity of Fe₂O₃ with high- index facets [104] and low- index facets [001], as well as the deep reduction reaction mechanism of these two facets. Surface reaction results show that the activity of Fe₂O₃[104] for oxidizing CO is greater than that of Fe₂O₃[001]. Fe₂O₃[104] was reduced into iron oxide at lower oxidation state or into iron, which could then be regenerated after being oxidized by O₂. The deep reduction reaction mechanism between oxygen carrier and CO shows that Fe₂O₃[104] can be completely reduced into Fe, and Fe₂O₃[104] exhibits high oxygen transfer ability. However, Fe₂O₃[001] can only be reduced to a limited extent, with a high energy barrier preventing further reduction, while it also exhibits limited oxygen transfer capacity. Results of experiments further verify the high reactivity and stability of Fe₂O₃[104].

In this work, N, S co-doped microporous carbon materials were successfully prepared using human hair and sucrose as carbon precursors via a two-step method that combined hydrothermal treatment and post-KOH activation. The morphology, pore texture, and surface chemical properties of the activated carbon materials were investigated by scanning electron microscopy, transmission electron microscopy, N₂ adsorption/desorption, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, and Fourier transform infrared spectroscopy. The electrochemical capacitive behavior of the prepared carbons was systematically studied in 6 mol·L^-1 KOH electrolyte. The maximum specific surface area of the prepared carbons was found to be 1849.4 m²·g^-1 with a porosity that mainly consisted of micropores. Nitrogen and sulfur contents varied from 1.6% to 2.5% and from 0.2% to 0.5% (atomic fraction (x)), respectively. The synergistic-positive effect of N, O, and S-containing groups caused the prepared carbons to exhibit a large pseudo-capacitance. High specific capacitances of up to 200 F·g^-1 at 0.2 A·g^-1 were observed, response to an energy density of 6.9 Wh·kg^-1. At a power density of 10000 W·kg^-1, the energy density was found to be 4.1 Wh·kg^-1. The present work highlights the significance of this new strategy to prepare N, S co-doped carbon materials from renewable biomass.

Carbonization of a nitrogen-containing polymer under inert atmosphere has been used to obtain nitrogen-enriched carbon materials. Herein, we synthesized dopamine-modified polypyrrole (PDA-PPy) via chemical polymerization, which was then carbonized under nitrogen atmosphere to produce nitrogen-doped porous carbon materials (NPC). The structure and morphology of the NPC were investigated by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). By regulating the molar ratio of pyrrole monomer to dopamine, the morphology of PDA-PPy and the capacitive performance of NPC could be controlled. At a current density of 0.5 A·g^-1, the specific capacitance of NPC-0.5 (the molar ratio of dopamine to pyrrole monomer is 0.5) is ca 210 F·g^-1. Even at a current density of 10 A·g^-1, the specific capacitance of NPC-0.5 is up to 134 F·g^-1 and the retention rate is 63.8%.

α-MnO₂ and Al-doped α-MnO₂ were synthesized via a hydrothermal method. The morphologies, structures, and electrochemical performances of as-synthesized un-doped and doped α-MnO₂ were studied. Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) show that these un-doped and doped α-MnO₂ are nanotube shaped. The band gaps of α-MnO₂ are investigated by ultraviolet-visible absorption spectroscopy, which indicates that the band gap of α-MnO₂ decreases upon Al doping. The electrochemical performances of un-doped and doped α-MnO₂ as electrode materials for supercapacitors were measured by cyclic voltammetry (CV) and galvanostatical charge/discharge tests. The specific capacitances of un-doped and Al-doped α-MnO₂ respectively reach 204.8 and 228.8 F·g^-1under a current density of 50 mA·g^-1. It was discovered that the electrochemical impedance of Al-doped α-MnO₂ was decreased by Al doping analyzed using electrochemical impedance spectra (EIS), which provides a beneficial increase to its electrochemical specific capacitance. Enhanced specific capacitance and preferable cycling stability (up to 1000 cycles) for Al-doped α-MnO₂ mean that these systems are favorable prospects for application in supercapacitors.

LiVPO₄F/C, as a cathode material of lithium- ion batteries, was prepared by carbon thermal reduction assisted sol-gel method. X-ray diffraction (XRD), scanning electron microscopy (SEM), galvanostatic charge-discharge cycles, cyclic voltammogram (CV), and electrochemical impedance spectroscopy (EIS) were employed to investigate the effects of sintering time and temperature on the structure and corresponding electrochemical performance of as prepared materials. At a sintering time of 4 h, pure phase LiVPO₄F/C material was obtained when the temperature is settled at 450 ℃. The as-produced LiVPO₄F/C exhibited discharge capacities of 193.2, 175.6, and 173.7 mAh·g^-1 at 0.1C, 0.5C, and 1.0C rates, respectively. Li₃V₂(PO₄)₃ impurities are formed and increased with increasing calcination temperature. When sintered at 650 ℃ Li₃V₂(PO₄)₃ is turn out to be the main phase. On the other hand, optimal duration time at high temperature could also inhibit the decomposition of LiVPO₄F and decrease the formation of Li₃V₂(PO₄)₃ impurities, improving electrochemical performance. Optimal conditions were found at a residence time of 3 h when the precursor is sintered at 550 ℃.

Electrostatic interactions between cationic polyamine and anionic surfactant cause assembly to form composite micelles. The anionic surfactant/cationic polyamine composite micelles can then act as a template to co-assemble with silica precursors to form mesostructured silica. Mesoporous silicas with different mesostructures and morphologies were obtained by changing the synthesis temperature, the amounts of cationic polyelectrolyte or silica precursor and the species of anionic surfactant. This anionic surfactant/cationic polyamine composite micelle template method comprises a general method for synthesizing mesoporous silicas.

The adsorption mechanism and wetting properties of aqueous solutions of branched cationic surfactants, hexadecanol glycidyl ether ammonium chloride (C₁₆GPC), and zwitterionic surfactant, hexadecanol glycidyl ether glycine betaine (C₁₆GPB) on a poly(tetrafluoroethylene) (PTFE) surface were investigated using sessile drop analysis. The influences of surfactant concentration on surface tension, contact angle, adhesional tension, PTFE-solution interfacial tension, and adhesion work were expounded. The results indicate that branched surfactant molecules lie parallel to the PTFE surface through hydrophobic interactions between the multi methylene groups of the alkyl chain and the solid surface below the critical micelle concentration (cmc). C₁₆GPC and C₁₆GPB molecules still adsorb onto PTFE because of the marked hindrance of branched chains to the formation of micelles above the cmc. The methylene group interactions with PTFE decrease and C₁₆GPC and C₁₆GPB molecules become straightened on the solid surface, which results in a clear decrease in PTFE-solution interfacial tension (γ_sl). For branched surfactants, an abrupt decrease in contact angle appears above the cmc.

Three amphiphilic peptides containing KKGRGDS as hydrophilic heads and VVVVVV, C12, and FAFAFA as hydrophobic tails (VVVVVVKKGRGDS (AP1), C₁₂KKGRGDS (AP2), FAFAFAKKGRGDS (AP3)) were designed and prepared using the standard solid-phase peptide synthesis (SPPS) technique. Three peptides assembled into spherical micelles under neutral conditions (pH 7.0) with a size of ~30 nm determined by transmission electron microscope (TEM). Dynamic light scattering (DLS) tests showed that their size distributions were uniform and narrow. In dilute hydrochloric acid (pH 5.0), peptide AP1 presented a sharp aciddependent demicellization transition, with no assembled particles found by TEM and no DLS peak in the range 1-1000 nm. However, the micellar structures of the amphiphilic peptides AP2 and AP3 did not disappear at pH 5.0. TEM results showed that AP2 assembly appeared through aggregation and the shape of AP3 micellar particles became non-spherical or irregular. AP2 assembly at pH 5.0 showed a multiple peak distribution and AP3 assembly showed a broad peak distribution in DLS, consistent with the TEM results. The changes in secondary structures of amphiphilic peptides AP1, AP2, and AP3 at pH 7.0 and 5.0 were confirmed by circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy. We then selected curcumin as a model drug to investigate the drug-loading capacity and in vitro release behavior of peptide AP1 micelles. As a result, AP1 is expected to comprise an ideal acid-responsive drug carrier for the intelligent delivery of anticancer drugs. The differences between AP1, AP2, and AP3 assembly behaviors in neutral and acidic conditions provide a novel and effective approach for regulating self-assembly of peptides. AP1 is expected to offer an ideal pH-responsive functional material.

A series of bimetallic PdAu catalysts with different structures were prepared by changing the loading sequence of Pd and Au for the hydrogenation of 2-ethylanthraquinone. Pd/Au/Al₂O₃ was obtained by loading Pd onto Au particles deposited onto an Al₂O₃ support with a hydrogenation efficiency up to 14.27 g·L^-1. According to X-ray diffraction, transmission electron microscopy, hydrogen temperature program reduction, and X-ray photoelectron spectroscopy measurements, the popcorn structure and unique electronic properties of the Pd species in the Pd/Au/Al₂O₃ catalyst resulted in the highest content of surface metallic Pd, which was the most active component for the reaction. What is more, the addition of Au can effectively reduce the amount of degradation products by suppressing side reactions.

Using silica as a support, 2-(diphenylphosphino)ethyltriethoxysilane (DPPES) was anchored on silica surface by a grafting method to produce a bonded phosphine (denoted as SiO₂(PPh₂)), which displays excellent performance. The supported SiO₂(PPh₂)/Rh catalyst was formed in situ in 1-octene hydroformylation with SiO₂(PPh₂) as ligand and Rh(acac)(CO)₂ as precursor (acac: acetylacetone). SiO₂(PPh₂) and SiO₂(PPh₂)/ Rh were characterized by Fourier transform infrared (FTIR) spectroscopy. The effects of the ratio of phosphine to rhodium ([P]/[Rh]) and reaction temperature on 1-octene hydroformylation were investigated. Results show that an increase of the ratio of phosphine to rhodium can greatly improve the selectivity for aldehydes and decrease the rhodium leaching in organic phase. Under the moderate conditions: [P]/[Rh]=12, 363 K, 2 MPa, and 1.5 h, the conversion of 1-octene and the selectivity for aldehydes were 98.4% and 95.3%, respectively. The catalytic activity could compare with homogeneous catalysis with DPPES or triphenylphosphine (TPP) as ligand. The reaction activity was clearly unchanged after the SiO₂(PPh₂)/Rh catalyst was reused four times, with the conversion of 1-octene remaining at 97.0%, the rhodium content leaching in organic phase detected by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) was less than 0.1%.

Polymethyl methacrylate (PMMA) microspheres were synthesized using an emulsifier-free emulsion polymerization method. A three-dimensionally ordered macroporous (3DOM) MgFe_0.1Al_1.9O₄ spinel-type oxide catalyst was prepared using the synthesized colloidal crystal templates and evaluated for oxidative dehydrogenation of ethylbenzene with CO₂. Several techniques, such as powder X-ray diffraction, scanning electron microscopy, temperature-programed reduction, and ⁵⁷Fe-Mössbauer spectra, were used to characterize the physicochemical properties of the catalyst. The results indicate that 3DOM MgFe_0.1Al_1.9O₄ has a hexa nal ordered arrangement, with a pore diameter of 230 nm and a shell thickness of 60 nm, and that most of its Fe species are incorporated into the spinel lattice. Compared with a nano MgFe_0.1Al_1.9O₄, the 3DOM MgFe_0.1Al_1.9O₄ catalyst exhibited a much higher catalytic stability and less carbon deposition. A possible explanation for the enhanced catalytic stability of 3DOM MgFe_0.1Al_1.9O₄ catalyst is discussed. The three-dimensionally ordered macroporous structure has a large effect on the diffusion of coke precursors and the stability of the catalyst.

Composite support CeZrYLa + LaAl was prepared by co-precipitation, and platinum catalyst supported on the composite support was prepared by impregnation. The behavior of the Pt catalyst for the reaction of NO reduction by CH₄ from the exhausts of natural gas vehicles (NGVs) was studied under stoichiometric conditions. Additionally, the effects of 10% (volume fraction, φ) H₂O and stoichiometric O₂ on the reaction in the presence of CO₂ were also investigated. Results show that N₂ and CO₂ were the main products for the different reactions, CO was detected under high temperature, and NO_x was detected under low temperature (in the presence of O₂, the NO_x was NO₂, whereas the NO_x was N₂O when no O₂ was present). In the presence of 10% (φ) H₂O, the conversion of CH₄ noticeably decreased and NO conversion remained unchanged, possibly because the presence of H₂O weakens the reforming reaction of CH₄ with CO₂, but does not affect the activity of NO reduction by CH₄. In the presence of stoichiometric O₂, there was an obvious increase of CH₄ conversion and a decrease of NO conversion. These could be explained by the competition between NO and O₂, where the oxidation of methane by O₂ is the main reaction, limiting the reaction of NO reduction by CH₄. Moreover, in the presence of 10% (φ) H₂O and stoichiometric O₂, CO₂ reforming of CH₄ was negligible. Numerous reactions were detected simultaneously, such as the oxidation of CH₄ by NO, steam reforming of CH₄, and the reduction of NO by CH₄, thus improving the conversions of CH₄ and NO.

The water-gas shift reaction (WGSR) has been carried out over CuO/Fe₂O₃ catalysts modified by different loadings of Al₂O₃ (0%-15% (w)), prepared by a stepwise co-precipitation method. Composite mixture CuFe₂O₄ was produced, and the crystalline size, redox property, and surface metallic Cu dispersion were manipulated. The appropriate introduction of Al₂O₃ can promote the phase transition of spinel CuFe₂O₄ from tetra nal to cubic, inhibit aggregation of Cu-crystallite, improve Cu dispersion, and increase the amount of weak basic sites, as confirmed using powder X-ray diffraction (XRD), Raman spectroscopy, N₂ physisorption, N₂O decomposition, and temperature-programmed desorption of carbon dioxide (CO₂-TPD) techniques. In addition, a temperature-programmed reduction of hydrogen (H₂-TPR) technique was used to investigate the reducibility of the modified CuO/Fe₂O₃ catalysts. It was found that the Al₂O₃-doping plays an important role in increasing the hydrogen consumption of the copper species, and decreasing reduction temperature. This means that the Al₂O₃ can promote a synergistic interaction between the copper and iron species in the CuO/Fe₂O₃ catalysts. Overall, the Al₂O₃-modified catalyst (10%(w)) has a smaller Cu particle size, better Cu dispersion, greater reducibility, and larger amount of weak basic sites, resulting in a much higher initial catalytic activity and better thermal stability.

Polyaniline (PANI) nanorods grown on layered graphitic carbon nitride (g-C₃N₄) sheets are synthesized by interfacial polymerization. The structure, morphology, and properties of the photocatalysts are characterized by Fourier transform infrared (FTIR), X- ray diffraction (XRD), and UV-visible (UV-Vis) spectroscopies, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and electrochemical analysis. Photocatalytic degradation of methylene blue is investigated to determine the photoactivity of the catalyst. The results suggest that g-C₃N₄ possesses od dispersion with an intercalated nanostructure and interfacial adhesion with PANI. In addition, the PANI/g-C₃N₄ composites retain the advantage of high thermal stability resident with g-C₃N₄. This is ascribed to a physical barrier effect on the emanation of degradation products and inhibited polymer motion. The resulting composites also show more intensive photocatalytic activity than does g-C₃N₄.

An Fe-loaded mesoporous silica SBA-15, Fe/SBA-15, was prepared by incipient wetness impregnation, characterized by X-ray diffraction (XRD), N₂ adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) techniques and used for heterogeneous Fenton oxidation of dye Rhodamine B (RhB) in aqueous solution. The characterization showed that the Fe/SBA-15 retained a mesoporous structure with a long-range ordered arrangement, reduced pore diameter and surface area, and existed as agglomerates of rod-like crystallites with a mean diameter of 0.6 μm. The Fe species occurred both inside and outside the support pores in the form of α-Fe₂O₃ crystallites. The removal of RhB in the presence of Fe/SBA-15 and H₂O₂ was shown to be caused by the synergistic effects of adsorption and catalytic oxidative degradation, and was closely related to Fe/SBA-15 dosage. Removal was almost independent of initial solution pH, with approximately 93% achieved at an Fe/SBA-15 dosage of 0.15 g·L^-1, initial RhB concentration of 10.0 mg·L^-1, H₂O₂/Fe³⁺ molar ratio of 2000:1; initial solution pH of 5.4 and 21 ℃. The Langmuir monolayer adsorption capacity of the Fe/SBA-15 was 99.11 mg·g^-1. In addition, Fe/SBA-15 can be easily regenerated by soaking in H₂O₂ then reused for up to six runs, with RhB removal greater than 80% and Fe leaching below 0.1 mg·L^-1 (or 0.6% (mass fraction)) for each run. A removal mechanism for RhB by Fe/SBA-15 and H₂O₂ was proposed based on the quenching tests, UV-Vis spectra, and gas chromatography-mass spectrometry (GC-MS) analysis. The heterogeneous Fenton catalyst Fe/SBA-15 can be applied to remove nonbiodegradable organics such as dye RhB.

A low-temperature hydrothermal route was applied to fabricate ZnO nano-arrays on fluorinated tin oxide (FTO)-coated glass substrates. The effects of the molar ratios of the precursor concentrations on the ZnO nano-arrays were studied with respect to morphology, optical properties, and growth mechanism. The results show that the length reduced with the increased molar ratios of precursor concentrations, and the diameter first increased then decreased. In general, the change of optical band gap followed the same trend as that for the change in diameter. When the molar ratio of precursor concentrations is 5:5, the optical band gap is 3.2 eV, which is similar to the theoretical value at room temperature. We propose that the optimal molar ratio of zinc nitrate (Zn(NO₃)₂) to hexamethylenetetramine (HMT, C₆H₁₂N₄) is 5:5 for the preparation of ZnO nano-arrays. Spike-shaped CuO/ZnO nano-arrays were also successfully synthesized using a two-step solution-system method. Field emission scanning electron microscope (FE-SEM) results show that there were a large number of copper oxide (CuO) nano-particles (NPs) deposited onto the ZnO nano-array surfaces to form spike-shaped structures. The covered CuO NPs exhibited improved photocatalytic properties over pure ZnO nano-arrays under UV irradiation, and the possible photocatalytic mechanism of the CuO/ZnO nano-heterojunction was discussed in detail.

Zeolite membranes, especially the MFI-type zeolite membranes, have attracted significant attention for decades because of their special properties. While organic templates such as tetrapropylammonium hydroxide (TPAOH) have typically been used for the synthesis of ZSM-5 zeolite and zeolite membranes, the templates remain trapped in the as-synthesized zeolite crystals. A common method for removing organic templates and generating porous frameworks is calcination; however, during this process, the channel structure may be affected. In particular, for ZSM-5 membranes, membrane defects may be produced and the separation efficiency therefore may decrease to some extent. In this study, the low-temperature hydrocracking of TPAOH in ZSM-5 zeolite crystals was studied under H₂/N₂, while N₂ adsorption, thermogravimetric (TG) analysis, Fourier transform infrared (FTIR) spectroscopy, temperature-programmed desorption of ammonia (NH₃-TPD), and Raman spectroscopy were used to characterize zeolite samples. The results show that the organic template in the pores of ZSM-5 can be effectively removed below 350 ℃ by low-temperature hydrocracking. Characterization analyses by BET specific surface area, TG, FTIR, and Raman spectroscopy demonstrated that a reducing atmosphere containing H₂ was more conducive to template removal at low temperature than atmospheres of air or N₂. The degree of template removal increased with temperature increasing. The BET surface area of the crystal after hydrocracking at 280 ℃ reached 252 m²·g^-1, although a small amount of organic residue remained. Furthermore, after hydrocracking at 350 ℃, the BET surface area reached 399m2·g^-1, and only trace amount of inorganic carbon residue remained. In addition, the introduction of hydrogen at low temperatures could prevent coke deposits on acid sites and thus ZSM-5 zeolite crystals had greater numbers of acidic sites after low-temperature hydrocracking.

Pyrrole (Py) was oxidized by ferric(III) chloride solution in water for the synthesis of polypyrrole (PPy) nanoparticles on the substrate slide by in-situ polymerization at room temperature. Zinc oxide nanorods grew on the PPy nanoparticles when in a water bath at 90 ℃. ZnO/PPy hetero-nanocomposites were obtained by a hydrothermal method and characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Gas sensors were fabricated based on the ZnO/PPy hetero-nanocomposites to detect ammonia at room temperature. The gas sensing properties of these hetero-nanocomposites were measured in the concentration range of 10×10^-6-150×10^-6 (volume fraction). The relationship of the sensitivity of the sensors to the ammonia concentration showed linearity. The gas sensor based on ZnO/PPy heteronanocomposites showed od selectivity to ammonia when in the presence of interfering gases such as methanol, acetone, and toluene. The formation mechanism of the ZnO/PPy hetero-nanocomposites was briefly analyzed.