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Monolithic catalysts with high catalytic activity bring about increasing interest in practical environmental purification field for volatile organic compounds (VOCs) degradation with low pressure drops. Monolithic CoMnAlO catalysts with varied Co/Mn molar ratio derived from in situ supported layered double hydroxides (LDH) film are prepared through ammonia hydrothermal growing on Al substrate following calcinations. The textural properties for CoMnAlO catalysts with low temperature reducibility, surface element species are controlled by tuning the initial Co/Mn molar ratio verified through H2-TPR and XPS spectra. CoMn2AlO film sample shows best activity with the temperature for 90% benzene decomposition (T90) around 238 °C with space velocity 300,000 ml gcat−1 h−1. The reaction rate of CoMn2AlO film is about 1.32 mmol gcat−1 h−1 at 260 °C with T99, which is nearly two times to that of Co3AlO film catalyst with 0.73 mmol gcat−1 h−1, because of the higher Mn4+/Mn3+ and Co3+/Co2+ atomic ratios and reducibility inducing by the synergistic effect of Co and Mn. The value is five times higher than CoMn2AlO powder catalyst with 0.26 mmol gcat−1 h−1, which is due to the great exposure active sites.

High reactivity and sintering resistance are key factors to design outstanding CH4 oxidation noble metal-based supported catalysts. Herein, we prepared and screened 0.5 wt% Pd/Al2O3 (among 0.3–3 wt% Pd loading) samples prepared by wet impregnation with very high CH4 catalytic activity. The hydrophobic modification of γ-Al2O3 support by triethoxyoctylsilane (TEOOS) exhibits further enhanced activity for CH4 oxidation, ca. T90 decrease from 375 °C to 350 °C with enhanced concentration of surface Pd0 sites. Besides, after Al2O3 protection layer deposition over the 0.5 wt% Pd/Al2O3 by atomic layer deposition (ALD), distinct higher temperature stability due to reduced agglomeration was demonstrated.

Herein, we reported the synthesis of well-defined Co3O4 nanoarrays (NAs) supported on a monolithic three-dimensional macroporous nickel (Ni) foam substrate for use in high-efficiency CO oxidation. The monolithic Co3O4 NAs catalysts were obtained through a generic hydrothermal synthesis route with subsequent calcination. By controlling the reaction time, solvent polarity and deposition agent, these Co3O4 NAs catalysts exhibited various novel morphologies (single or hybrid arrays), whose physicochemical properties were further characterized by using several analytical techniques. Based on the catalytic and characterization analyses, it was found that the Co3O4 NAs-6 catalyst with nanobrush and nanomace arrays displayed enhanced catalytic activity for CO oxidation, achieving an efficient 100% CO oxidation conversion at a gas hourly space velocity (GHSV) 10,000 hr− 1 and 150°C with long-term stability. Compared with the other Co3O4 NAs catalysts, it had the highest abundance of surface-adsorbed oxygen species, excellent low-temperature reducibility and was rich in surface-active sites (Co3 +/Co2 + = 1.26).

Zinc cadmium sulfide solid solution (ZnxCd1−xS) photocatalysts have received significant attention in energy and environmental applications because of their wide and strong visible light absorption range. However, the high photogenerated electron–hole pair recombination rate is an innate problem for their application. In this study, Cu2S/Zn0.67Cd0.33S (CZCS) nanosheet heterojunctions were fabricated by the in situ topotactic hydrothermal transformation of CuZnCdAl layered double hydroxide (LDH) precursors. Structural and morphological characterization indicated that the CZCS nanosheets were 2D/2D atomic-level in-plane heterojunctions with matched crystalline orientation because of their intergrowth structure originating from the topotactic sulfurization of CuZnCdAl LDH precursors. This in-plane intergrowth structure enhanced the separation of photogenerated electron–hole pairs based on a direct Z-scheme mechanism, which, in addition to providing a wide light absorption range and appropriate flat band potential, endowed excellent photocatalytic hydrogen production at the rate of 15.27 mmol h−1 g−1 (about 3.82 times that of pure Zn0.67Cd0.33S) from water splitting under visible light irradiation without the additive Pt cocatalysts. This photocatalyst with a superior photocatalytic activity and cycling stability can serve as a hopeful candidate for applications in the energy and environment field.

CuO–CeO2 nanocatalysts with different amounts of Mn dopping (Mn/Cu molar ratios of 0.5 : 5, 1 : 5 and 1.5 : 5) were synthesized by flame spray pyrolysis (FSP) method and tested in the catalytic oxidation of CO. The physicochemical properties of the synthesised samples were characterized systematically, including using X-ray diffraction (XRD), Raman spectroscopy, field-emission scanning electron microscopy (FESEM), Brunauer–Emmett–Teller (BET), X-ray photoelectron spectroscopy (XPS), oxygen-temperature programmed desorption (O2-TPD), hydrogen-temperature programmed reduction (H2-TPR) and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). The results showed that the 1Mn–Cu–Ce sample (Mn/Cu molar ratio of 1 : 5) exhibited superior catalytic activity for CO oxidation, with the temperature of 90% CO oxidation at 131 °C at a high space velocity (SV = 60 000 mL g−1 h−1), which was 56 °C lower than that of the Cu–Ce sample. In addition, the 1Mn–Cu–Ce sample displays excellent stability with prolonged time on CO stream and the resistance to water vapor. The significantly enhanced activity was correlated with strong synergetic effect, leading to fine textual properties, abundant chemically adsorbed oxygen and high lattice oxygen mobility, which further induced more Cu+ species and less formation of carbon intermediates during the CO oxidation process detected by in situ DRIFTS analysis. This work will provide in-depth understanding of the synergetic effect on CO oxidation performances over Mn doped CuO–CeO2 composite catalysts through FSP method.

As an emerging p-conjugated materials, graphitic carbon nitride (g-C3N4) has captured worldwide attention due to impending energy crisis and increasingly serious environmental contamination. In this work, the two-dimensional (2D) MgFe mixed metal oxide (MMO) derived from the layered double hydroxides precursor was employed to construct 2D/2D nanosheet heterojunction with g-C3N4. The formed CN/MgFe-30 nanosheet heterojunctions exhibited the optimal photocatalytic hydrogen production about 6.64 times (1.26 mmol/g−1·h−1) than that of pure g-C3N4 under the visible light irradiation, which were attributed to unique inter-plane 2D/2D structure and excellent synergistic effect between g-C3N4 and MgFe MMO. The experiment characterization proved that MgFe MMO nanosheet not only suppressed the overgrowth of g-C3N4, resulting in the formation of nanoscale g-C3N4, but also facilitated the photoinduced carrier separation and transfer based on 2D/2D CN/MgFe-X nanosheet heterojunctions. This proposed synthesis strategy pave a way to realize the large-scale production of nano-g-C3N4 based 2D/2D nanosheet heterojunctions photocatalysts for hydrogen production.

The synthesis of effective and recyclable Fenton-like catalyst is still a key factor for advanced oxidation processes. Herein, magnetic porous Fe3O4/carbon octahedra were constructed by a two-step controlled calcination of iron-based metal organic framework. The porous octahedra were assembled by interpenetrated Fe3O4 nanoparticles coated with graphitic carbon layer, offering abundant mesoporous channels for the solid-liquid contact. Moreover, the oxygen-containing functional groups on the surface of graphitic carbon endow the catalysts with hydrophilic nature and well-dispersion into water. The porous Fe3O4/carbon octahedra show efficiently heterogeneous Fenton-like reactions for decomposing the organic dye methylene blue (MB) with the help of H2O2, and nearly 100% removal efficiency within 60 min. Furthermore, the magnetic catalyst retains the activity after ten cycles and can be easily separated by external magnetic field, indicating the long-term catalytic durability and recyclability. The good Fenton-like catalytic performance of the as-synthesized Fe3O4/carbon octahedra is ascribed to the unique mesoporous structure derived from MOF-framework, as well as the sacrificial role and stabilizing effect of graphitic carbon layer. This work provides a facile strategy for the controllable synthesis of integrated porous octahedral structure with graphitic carbon layer, and thereby the catalyst holds significant potential for wastewater treatment.

Direct Z-scheme heterojunction can effectively enhance the photocatalytic activity due to its low carrier recombination rate and high redox ability. In this study, a 2D/2D ZnO/ZnxCd1−xS single crystal nanosheet heterojunction is synthesized in situ by topotactic sulfurization/oxidization pyrolysis of Zn/Cd/Al layer double hydroxides (LDHs). Its unique structure provides not only numerous intimate interfaces but also a direct Z-scheme junction. The in situ topotactic fabrication of ZnO by the oxidation process causes some Zn ions to dissolve out from the Zn0.67Cd0.33S solid solution nanosheets with increase in annealing temperature and time. The longer the time for oxidation, the more ZnO is obtained. The formation of ZnO yields 2D/2D ZnO/ZnxCd1−xS single crystal nanosheet heterojunction, which increases the visible light absorption and boosts the separation of photogenerated carriers. The ZnO/ZnxCd1−xS-4 single crystal nanosheet heterojunction presents the highest photocatalytic activity under visible light irradiation (38.93 mmol h−1 g−1), which is nearly 16.93 times higher than that of Zn0.67Cd0.33S-300, and an external quantum efficiency of 40.97% at λ = 420 nm. The proposed synthetic route for the construction of 2D/2D ZnO/ZnxCd1−xS single crystal nanosheet provides a direct Z-scheme structure with highly efficient photocatalytic hydrogen evolution activity.

Advanced integrated nanoarray (NA) catalysts have been designed by growing metal-doped Co3O4 arrays on nickel foam with robust adhesion. Ternary MCo2O4 NA catalysts were prepared by doping urchin-like Co3O4 with different transition metals (Cu2+, Mn2+, Fe2+, Ni2+, Zn2+, Fe3+ and Al3+). These catalysts exhibited novel morphologies and can be directly applied as monolithic materials for CO oxidation. Among the MCo2O4 NA catalysts, CuCo2O4 nanoneedles manifested the highest catalytic activity in dry air, achieving an efficient 100% CO oxidation conversion of 20 000 h−1 at 146 °C, due to its reducibility at lower temperature, lattice distortion of the spinel structure, and abundant surface-adsorbed oxygen (Oads). The doped catalytic systems were further optimized by controlling the volume ratio of reactive components in the mixed solvent, the Cu or Mn contents to determine excellent catalysts for direct application to CO oxidation at 1.0 vol% moisture. Penthorum chinense-like MnCo2O4 NAs showed optimal catalytic performance at 1 vol% moisture (T100 = 175 °C), with activity higher than that of the CuCo2O4 NA catalyst, indicating that the synergistic effect between MnOx and Co3O4 improved the moisture resistance and stability. It was concluded that the moisture resistance provided by introducing active sites on Co-based catalysts decreased as follows: Mn sites > Co sites > Cu sites > Ni sites. MCo2O4 NAs, with predominantly exposed {110} surfaces, showed higher catalytic activity than catalysts with exposed {111} surfaces. This study suggests that the as-prepared MnCo2O4 NAs anchored on 3D Ni foam with remarkable moisture resistance have potential applications in CO oxidation.

A generic hydrothermal synthesis route has been successfully designed and utilized to in situ grow highly ordered Co3O4 nanoarray (NA) precursors on Ni substrates, forming a series of Co3O4 nanoarray-based monolithic catalysts with subsequent calcination. The morphology evolution of Co3O4 nanostructures which depends upon the reaction time, with and without CTAB or NH4F is investigated in detail, which is used to further demonstrate the growth mechanism of Co3O4 nanoarrays with different morphologies. CO is chosen as a probe molecule to evaluate the catalytic performance over the synthesized Co-based oxide catalysts, and the effect of morphological transformation on the catalytic activity is further confirmed via using TEM, H2-TPR, XPS, Raman spectroscopy and in situ Raman spectroscopy. As a proof of concept application, core-shell Co3O4 NAs-8 presenting hierarchical nanosheets@nanoneedle arrays with a low density of nanoneedles exhibits the highest catalytic activity and long-term stability due to its low-temperature reducibility, the lattice distortion of the spinel structure and the abundance of surface-adsorbed oxygen (Oads). It is confirmed that CO oxidation on the surface of Co3O4 can proceed through the Langmuir-Hinshelwood mechanism via using in situ Raman spectroscopy. It is expected that the in situ synthesis of well-defined Co3O4 monolithic catalysts can be extended to the development of environmentally-friendly and highly active integral materials for practical industrial catalysis.

Ceria zirconia solid solution with high oxygen storage capacity (OSC) and thermal stability under 1000 ​°C is quite important for support materials in three-way catalysts (TWCs). In this work, Ce1-xZrxO2 with different Zr dopants (x ​= ​0, 0.125, 0.250 and 0.375) have been prepared by flame spray pyrolysis (FSP) with carboxylic acid or ethanol and carboxylic acid (v:v 1:4) solvents. The influences of Zr content and the addition of ethanol into carboxylic acid on the OSC performance and thermal stability have been systematically characterized by X-ray diffraction (XRD), N2 adsorption-desorption, Raman analysis, field emission scanning electron microscope (FESEM), high resolution transmission electron microscope (HRTEM), X-ray photoelectron spectroscopy (XPS), hydrogen-temperature programmed reduction (H2-TPR), and pulse thermal analysis using H2 as reducing agent. The presence of cubic-tetragonal interfaces in the Ce0.750Zr0.250O2 sample can enhance the formation of oxygen vacancies and the mobility of lattice oxygen in ceria-zirconia solutions, which results in the largest OSC (349 ​μmol ​g−1) among the fresh samples. The cubic-tetragonal interfaces in the Ce0.750Zr0.250O2 sample can also promote the thermal stability under 1000 ​°C to preserve better OSC (202 ​μmol ​g−1) than other aged samples. Furthermore, after adding with ethanol into carboxylic acid solvent, the OSC of the sample further increases to 371 ​μmol ​g−1 for the increment of oxygen vacancy concentration. It is worthy to note that the introduction of ethanol can suppress Zr migration from the lattice to the surface of CeO2 at high temperature, further enhancing OSC (240 ​μmol ​g−1) and thermal stability.

A series of silica supported Mn–Ce composite oxides with different Mn/Ce molar ratios were obtained by a simple and environment-friendly oxalate route. The physical and chemical properties were characterized by TG, BET, SEM, TEM, XPS and TPR analysis. All catalysts showed excellent activity towards deep oxidation of benzene. The effects of Mn/Ce ratio, calcination temperature on the structure and catalytic activity of catalysts were investigated. Catalyst from nitrate precursor was also characterized to compare the influence of different precursors. The 6Mn4Ce sample from oxalate route sintered at 400 °C showed the maximum reaction rate of 0.50 mmol gcat−1h−1; T90 of the catalyst is 216 °C. The catalytic activity is related to surface area, pore size distribution, surface elemental species, particle size distribution and low temperature reducibility which may derived from synergistic effect between manganese and cerium oxide. Compared with nitrate precursors, catalyst from oxalate route can be more finely dispersed on the pores of silica without damaging the pore structure of support. The role of silica is not only a support, but also an in situ reaction site for precursor’s decomposition, which ensure the finely distribution of active components. In addition, the best catalyst showed good stability with prolonged time on stream.

Particulate matter (PM) from cooking has caused seriously indoor air pollutant and aroused risk to human health. It is urged to get deep knowledge of their spatial-temporal distribution of source emission characteristics, especially ultrafine particles (UFP

Ce/MnAl and MnAl mixed metal oxides catalysts have been obtained by calcination of layered double hydroxides precursors. The composite oxides catalysts were studied in total oxidation of benzene. Physicochemical properties of all the catalysts were characterized by using a series of specific analytical techniques. The results revealed that the 0.2Ce/MnAl catalyst exhibited the highest catalytic performance with T90 about 210 °C at a high space velocity (SV = 60,000 mL g− 1 h− 1), ascribed to its lower-temperature reducibility, the abundant surface lattice oxygen (Olatt), and synergetic effect between Mn4 + and Ce3 +/Ce.

CuO-CeO2 nanocatalysts with varying CuO contents (1, 5, 9, 14 and 17 wt %) were prepared by one-step flame spray pyrolysis (FSP) and applied to CO oxidation. The influences of CuO content on the as-prepared catalysts were systematically characterized by X-ray diffraction (XRD), N2 adsorption-desorption at &minus, 196 &deg, C, field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and hydrogen-temperature programmed reduction (H2-TPR). A superior CO oxidation activity was observed for the 14 wt % CuO-CeO2 catalyst, with 90% CO conversion at 98 &deg, C at space velocity (60,000 mL &times, g&minus, 1 &times, h&minus, 1), which was attributed to abundant surface defects (lattice distortion, Ce3+, and oxygen vacancies) and high reducibility supported by strong synergistic interaction. In addition, the catalyst also displayed excellent stability and resistance to water vapor. Significantly, in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) showed that in the CO catalytic oxidation process, the strong synergistic interaction led readily to dehydroxylation and CO adsorption on Cu+ at low temperature. Furthermore, in the feed of water vapor, although there was an adverse effect on the access of CO adsorption, there was also a positive effect on the formation of fewer carbon intermediates. All these results showed the potential of highly active and water vapor-resistive CuO-CeO2 catalysts prepared by FSP.

Hierarchically porous manganese–nickel composite oxides (MNCOs) were successfully synthesized by an oxalate route and further applied for catalytic removal of benzene. Among these catalysts, the best one was Mn2Ni1 mixed oxides which exhibited uniform hierarchical lithops-like topography, a rich porous structure and a high surface area of 201.1 m2 g−1. The temperature required for a benzene conversion of 90% over this catalyst was ca. 232 °C under the conditions of a benzene concentration of 1000 ppm in air and a high space velocity of 120000 mL g−1 h−1, which was 54 °C lower than that over the non-porous MNCO particles prepared by a traditional approach. The reaction kinetic study showed that the apparent activation energy (45.2 kJ mol−1) for the total oxidation of benzene over the Mn2Ni1 oxide catalyst was much lower than those (72.4–97.2 kJ mol−1) over other catalysts. With XPS and H2-TPR analyses, the porous MNCOs have a higher content of surface-adsorbed oxygen species and better low-temperature reducibility which can be ascribed to a possible synergetic effect between Mn and Ni ions in the spinel mixed oxides.

Mesoporous CoMnAl mixed metal oxide catalysts with various Co/Mn atomic ratios have been obtained by calcination at 450 °C of layered double hydroxide (LDH) precursors prepared by the NH4OH co-precipitation–hydrothermal method without distinct MnCO3 peaks. The catalysts exhibited high efficiency for total oxidation of volatile organic compounds (VOCs). The physicochemical properties of the catalysts were characterized using several analytical techniques. Among them, CoMn2AlO shows the optimal activity and the temperature required to achieve a benzene conversion of 90% (T90) was about 238 °C, with a reaction rate and activity energy (Ea) of 0.24 mmol gcat−1 h−1 and 65.77 kJ mol−1 respectively. This temperature was 47 °C lower than that on the Co3AlO sample with a lower reaction rate of 0.19 mmol gcat−1 h−1 and a higher Ea 130.31 kJ mol−1 at a high space velocity (SV = 60 000 mL g−1 h−1). The effects of calcination temperature on the textural properties and catalytic activity of the CoMn2AlO catalyst were further investigated. The as-prepared CoMn2AlO-550 sample displayed superior catalytic activity, with T90 at 208 °C, compared CoMn2AlO-450. The formation of a solid solution with high surface area, rich oxygen vacancies, high Mn4+/Mn3+ and Co3+/Co2+ ratios and low-temperature reducibility made a great contribution to the significant improvement of the catalytic activity.

Homogeneous porous and curve plated CoxNiAlO composite metal oxide catalysts are obtained from the thermal decomposition of CoxNiAl-layered double hydroxide (LDH) precursors, which are prepared by urea co-precipitation with surfactant, followed by a hydrothermal treatment. The as-prepared samples were characterized by XRD, BET, SEM, TEM, H2-TPR and XPS. The Co3AlO sample shows 90% benzene conversion (T90) at 236 °C at a high space velocity (SV = 60000 mL g−1 h−1), and possesses much higher activity than Co3AlO prepared with NaOH co-precipitation without surfactant, with T90 = 288 °C. This is mainly correlated with the narrower pore size (2.9 vs. 17.2 nm) and lower temperature reducibility (319 vs. 360 °C). The Co2NiAlO sample exhibits enhanced activity at T90 = 227 °C with the low activation energy of 39.0 kJ mol−1, and its lower temperature reducibility is ascribed to the larger amount of surface accessible Co3+. The Co2NiAlO sample owns good reproducibility and superior reversibility and long stability with prolonged time on benzene stream in the presence of 3.5% water vapor. Moreover, a monolithic Co2NiAlO film catalyst is fabricated by the thermal decomposition of an LDH film precursor through an in situ growth methodology, with a high reaction rate of 1.21 mmol g−1 h−1 under T90 = 275 °C.

A hierarchical CoII2.8CoIII1 layered double hydroxide (LDH) nanostructure was constructed through a facile topochemical transformation route under a dynamic oxygen atmosphere. Self-assembled coral-like CoAl LDH nanostructures via the homogeneous precipitation method were also inspected under different ammonia-releasing reagents and solvents. Benzene and toluene were chosen as probe molecules to evaluate their catalytic performance over the metal oxide CoCoO and CoAlO calcined from their corresponding LDH precursors. Nanocatalyst of trivalent Co ions replaced Al3+ ions in the bruited-like layer had a higher catalytic activity (T99(benzene) = 210 °C and T99(toluene) = 220 °C at a space velocity = 60 000 mL g−1 h−1). Raman spectroscopy, XPS and H2-TPR demonstrated the existence of abundant high valence Co ions that serve as active sites. TPD verified the types of active oxygen species and surface acid properties. It was concluded that the high valence Co ions induced excellent low-temperature reducibility. Surface Lewis acid sites and the surface Oads/Olatt molar ratio (0.61) played relevant roles in determining its catalytic oxidation performance. Our design in this work provides a promising approach for the development of nanocatalysts with exposed desirable defects.

A reversible pH-modified blue to green luminescent transition system was constructed by encapsulating bis(2-(2-hydroxyphenyl)benzothiazolate) zinc (Zn(BTZ)2) within poly(styrene-b-acrylic acid) (PS-b-PAA) micelles. The system can respond to changes in the external pH environment from alkaline (7.0–10.5) to weakly acidic (4.5–7.0) conditions, which are absent for the pristine Zn(BTZ)2 dimethylformamide solution state, and designated as blue and green micelles, respectively. The tunable pH-modified luminescent behavior probably originates from changes in the Zn(BTZ)2 molecular packing modes modified by the shrink/swell morphology transition of the copolymer micelles due to the reversible ionization of the carboxylic group. The emission transition from blue to green can be further detected through affecting the Zn(BTZ)2 intermolecular interactions upon grinding the Zn(BTZ)2 powder. The micelles were further fabricated to form films by electrostatic layer-by-layer assembly with positively charged layered double hydroxide (LDH) nanosheets, which are responsive to acidic and alkaline atmospheres and show higher UV resistance compared to the micelles/PDDA (poly(dimethyldiallylammonium) chloride) film.

Based on shooting and bouncing ray tracing/image method (SBR/IM), millimeter wave (mmWave) propagation characteristics was simulated and analyzed inside a bus at 60 GHz. The statistical analysis of simulation results considering large scale fading and delay parameters has been performed, such as path loss and root mean square (RMS) delay spread obtained for some fixed positions in the bus, providing good agreement with statistics for known literature. In addition, the path loss of the aisle and the received power of the whole intra-vehicle are simulated and analyzed. This study, which provides a theoretical basis for simplifying the millimeter wave propagation model in intra-vehicle, is conductive to the network planning and optimization of wireless communication within the vehicle, and lays the foundation for the future development of the fifth generation mobile communication technology.

A co-current flow rotating packed bed was applied to remove volatile organic compounds (VOCs) by sodium hypochlorite (NaClO) and surfactant (sodium dodecyl benzene sulfonate, SDBS) from air stream. Xylene was used as a model VOC herein. The effect of pH, concentration of NaClO and SDBS solution, liquid flow rate, gas flow rate and rotational speed on xylene removal efficiency and overall mass transfer coefficient (KGa) were discussed. Then, a correlation for KGa of the co-current rotating packed bed was proposed by fitting the experimental data of KGa and independent variables of liquid/gas ratio, rotational speed, pH, NaClO concentration and treatment time, which was in good agreement with the experimental data (the deviation≤±30%).

In this paper, the propagation characteristics of UWB (Ultra-wideband) signal in the indoor NLOS (Non-Line-of-Sight) environment are discussed based on the time-domain ray tracing method. Propagation characteristics are analyzed by considering of multipath propagation mechanisms including direct ray, reflection and transmission, such as the time-domain normalized electric field intensity, instantaneous power delay profile, received power and so on. These results provide the theoretical basis for wireless communication network coverage and optimization of UWB signal in the complex environment of indoor.