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Catalytic oxidation can efficiently eliminate nitrogen-containing volatile organic compounds (NVOCs) and suppress the generation of toxic NOx in order to avoid secondary pollution. In this study, mesoporous SiO2-confined LaMnO3 perovskite nanoparticles with high dispersion were successfully prepared by a citric acid-assisted deposition method (LMO/SiO2-SD) and tested for the oxidation of n-butylamine. The method utilized the synergistic effect of abundant active hydroxyl groups existing on the SiO2 gel surface and citric acid, rendering the metal ions more uniformly scattered on the SiO2 surface. Strikingly, the LMO/SiO2-SD sample exhibited the optimum catalytic performance (T90 at 246 °C) and the highest N2 selectivity, which was mainly ascribed to its abundant surface acid sites, superior low-temperature reducibility and higher ratio of surface Mn4+ species. The apparent activation energy (Ea) for n-butylamine oxidation over LMO/SiO2-SD sample was 29.0 kJ mol−1. Furthermore, the reaction mechanism of n-butylamine oxidation was investigated by in situ FITR and a reasonable reaction route for n-butylamine oxidation over the LMO/SiO2-SD sample was proposed.

A series of mesoporous Mn–Ti amorphous oxides (MnaTi1−a) fabricated by a combined strategy of in situ deposition and freeze-drying were studied for the selective catalytic reduction of NO with NH3 (NH3-SCR) at low temperature. The physico-chemical properties of MnaTi1−a catalysts were characterized systematically by XRD, TEM, Raman, EXAFS, N2-sorption, XPS, H2-TPR and NH3-TPD. The results revealed that the increased amount of Mn4+ species greatly promoted the NO conversion at low temperature. Additionally, the highly dispersed active sites, abundant surface Lewis acid sites and strong interaction between Mn and Ti contributed to the remarkable low-temperature SCR activity. Among these MnaTi1−a catalysts, the Mn0.5Ti0.5 catalyst exhibited the best low-temperature NH3-SCR performance (61% NO conversion at 100 °C and over 95% N2 selectivity at 150–250 °C) and excellent H2O/SO2 durability. In situ FTIR was used to investigate the reaction mechanism, and the results indicated that both the L–H and E–R mechanisms were present and NH3-SCR mainly proceeded via the L–H reaction pathway at low temperature.

By combining the excellent surface-enhanced Raman scattering (SERS) activity of Ag nanoparticles (AgNPs), the well-separated pyramid arrays of the pyramidal silicon (PSi) and unique physical/chemical properties of molybdenum disulfide (MoS2), the MoS2@AgNPs@PSi substrate shows high performance in terms of sensitivity, uniformity, reproducibility and stability. By using rhodamine 6G (R6G) as probe molecule, the SERS results indicate that the MoS2@AgNPs@PSi substrate is superior to the AgNPs@PSi, AgA@PSi (the second annealing of the AgNPs@PSi) and the MoS2@AgNPs@flat-Si substrate. The MoS2@AgNPs@PSi substrate also shows the reasonable linear response between the Raman intensity and R6G concentration. The maximum deviations of SERS intensities from 20 positions on a same MoS2@AgNPs@PSi substrate and 10 MoS2@AgNPs@PSi substrates in different batches are less than 7.6% and 9%, respectively, revealing the excellent uniformity and reproducibility of the substrate. Besides, the SERS substrate has a good stability, the Raman intensity of the MoS2@AgNPs@PSi substrate only drop by 15% in a month. The corresponding experimental and theoretical results suggest that our proposed MoS2@AgNPs@PSi substrate is expected to offer a new and practical way to accelerate the development of label-free SERS detection.

We proposed a high sensitivity and a high resolution surface plasmon resonance sensor composed of graphene–WS2 hybrid nanostructure and Au–Ag bimetallic-layers film. The bimetallic-layer configuration uses the high sensitivity of gold and the narrow full width at half maximum (FWHM) of silver to improve the sensor's sensitivity and resolution respectively. Graphene and WS2 serve as an effective light absorption medium. Once they cover the bimetallic-layer, the sensitivity can be further improved significantly. Graphene–WS2–Au–Ag model shows a higher sensitivity and higher resolution than that of the conventional sensing scheme where pure Au thin film is used. In our paper, we mainly use Fresnel equations and the transfer matrix method (TMM) to study the reflectivity and sensitivity as well as the full width at half maximum (FWHM) of the SPR sensor.

In this paper, we designed a 2D distance and rotation angle plasmon ruler based on Fano resonance of a trimer nanostructure, which consists of a concentric square nanoring–disk and an outside nanorod (CSRDR). The Fano dip energy and depth are fairly sensitive to the nanometer-scale displacements and rotations, when the nanodisk moves in all direction and rotates around its center. When the symmetry of the nanoring is broken, we can identify the moving and rotating direction of the nanodisk more accurately. We use the CSRDR nanostructure which supports a narrow line-width as a 2D plasmon ruler, which can enhance the sensitivity of a plasmon ruler significantly.

A new and effective in situ impregnation/deposition technique of chemical layer deposition (CLD) on a gas–solid interface is developed for fast and controllable film deposition and functional nanostructure design. Using CLD, a series of nanostructured Al(BH4)3(NH3)6@porous carbon composites are successfully produced, and a significant improvement of the hydrogen storage properties of Al(BH4)3(NH3)6 is achieved with tunable dehydrogenation temperature ranging from 114 to 175 °C, enhanced dehydrogenation kinetics with a low activation energy of 65.6 KJ mol−1 compared to 105.5 KJ mol−1 for the bulk counterpart, and a significantly increased H2 purity from 67.4% to 93.5%.

Two different approaches, the conventional solvent evaporation induced self-assembly (EISA) and the novel solvent evaporation induced aggregating assembly (EIAA), were employed to synthesize ordered mesoporous silicas (OMSs), respectively, by using amphiphilic diblock copolymer poly(ethylene oxide)-b-poly(methyl methacrylate) as the template, with an aim to systematically investigate the difference of the two approaches and their effect on the textural properties of the obtained porous materials. The mesoporous silicas synthesized via the two methods possess face centered cubic (fcc) mesostructure, large pore size and high surface area. However, compared with the OMSs with a film-like morphology from EISA, the OMSs from the EIAA have a particle-like morphology, thinner pore wall and higher surface area, which is favorable for their applications. More importantly, the novel EIAA process is more versatile and can be used to synthesize ordered mesoporous silicas and silica-based nanostructured materials with different morphologies. By introducing ethanol as the additive in the EIAA system, unique mesoporous silica spheres with a diameter of 1–5 μm, large pore size (∼16.8 nm), huge window size (∼8.9 nm), and high surface area (∼482 m2 g−1) can be synthesized. Through increasing the content of water, uniform silica hollow spheres (20–40 nm in diameter) and silica nanotubes (diameter ∼30 nm) can be obtained by using templates with higher and lower molecular weight, respectively.