Small Porosity Research Articles

Ultrathin Cellulose Voronoi-Nanonet Membranes Enable High-Flux and Energy-Saving Water Purification.

Creating a desirable porous membrane with high-flux and energy-saving properties for the purification of water containing submicron-sized contaminants, especially pathogenic microbes, is of great significance, yet a great challenge. Herein, we demonstrate a facile methodology to construct an innovative membrane with continuous cellulose Voronoi-nanonet structures via nonsolvent-induced phase separation. This approach enables cellulose Voronoi nanonets to tightly weld with electrospun nanofibrous substrates by controlling the solvent-nonsolvent mutual diffusion process. The resultant membranes exhibit integrated properties of small pore size (0.23 μm), high porosity (90.7%), good interconnectivity, and ultrathin thickness (∼600 nm, 2 orders of magnitude thinner than the conventional microfiltration membrane). As a result, the prepared membranes can effectively intercept submicron particles (∼0.3 μm) with robust rejection efficiency (>99.80%) and ultrahigh permeation flux (maximum of 8834 L m-2 h-1) under an extremely low driving pressure (≤20 kPa). More importantly, prominent bacterial rejection efficiency with a log reduction value (LRV) of 8.0 (overcoming the previous limitation of LRV <7) and outstanding antifouling function are also achieved for the membranes. The successful fabrication of such a versatile membrane may provide new insights into the development of next-generation high-performance separation materials for various applications.

Pore-scale investigation on the heat-storage characteristics of phase change material in graded copper foam

The mechanisms responsible for the effect of metal foam, having a varying degree of porosity, on the phase change process in a phase change material (PCM) are not clearly understood. In this work, the pore-scale heat storage performance of the graded metal foams saturated with paraffin has been investigated using the computational fluid dynamics (CFD) method. The results demonstrate that the metal foam with a graded porosity accelerates the heat storage of PCM. In terms of the gradient dimension of the metal foam, the full melting time of the negative model 2 has been observed to be shortened by 2.6% as compared to the uniform model 1 and reduced by 15.5% as compared to the positive model 3. This is because the smaller the porosity of metal foam is, the faster the melting conducts. For the negative model, the relatively small porosity region is closer to the heat source than the large porosity region, which makes the heat transfer enhancement effect more evident than the weakening effect. Meanwhile, the full melting time shows an initial increasing trend, followed by a decrease for an increase in the porosity gradient difference. The optimal gradient difference is found to be −0.12 at the average porosity of 0.86 in this study.

Iron Ion‐Doped Tricalcium Phosphate Coatings Improve the Properties of Biodegradable Magnesium Alloys for Biomedical Implant Application

AbstractIron‐substituted tricalcium phosphate (Fe‐TCP) (about 1 wt%) coatings are deposited on biodegradable Mg‐Ca alloys to improve their corrosion resistance. Pulsed laser deposition technique is used for coating preparation. The 2 µm thick coatings are uniformly deposited. (Ca+Fe)/P ratio for the Fe‐TCP coatings is close to the stoichiometric value. Coated and uncoated Mg‐Ca alloys are subjected to electrochemical tests to investigate the influence of the coatings on their corrosion resistance in simulated body fluid (SBF). Tafel curves corresponding to coated and uncoated Mg‐Ca alloy samples in SBF show that the most electropositive corrosion potential is reached for the Fe‐TCP‐coated Mg‐Ca deposited at 300 °C. From the obtained and calculated values of the electrochemical parameters it follows that this sample possesses the best characteristics: it has the smallest porosity and the highest protective efficiency in SBF. Equine adipose tissue‐derived mesenchymal stem cells are used for 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide test and osteogenic differentiation study. Microbiology tests are performed with Escherichia coli (E. coli) (Gram−) and Staphylococcus aureus (Gram+) bacteria strains. The Fe‐TCP‐coated Mg‐Ca deposited at 300 °C is characterized by the best cytocompatibility and good ability to inhibit the growth of E. coli and is recommended for biomedical implant applications.

Nanoporous anodic alumina (NAA) prepared in different electrolytes with different pore sizes for humidity sensing

The aim of present study is to design a simple and reliable capacitive humidity sensor based on the nanoporous alumina prepared by a two-step anodization technique. Owing to long-range-ordered structure of porous alumina, its electrical properties are sensitive to moisture; with the result, it finds potential applications as humidity sensor. Anodization parameters have been optimized to prepare a series of porous alumina samples in different acidic electrolytes, and the effect of pore size, porosity, and uniformity of pores on humidity sensing was investigated. The sensitivity of the sensor fabricated in oxalic acid at 40 V is 2–3 times higher than the sensors fabricated in sulphuric acid at 25 V and phosphoric acid at 98 V. Its enhanced sensitivity is justified by small porosity and uniformity in pore distribution of porous alumina. The sensitivity of the sensor fabricated in oxalic acid solution with pore diameter 34 ± 1 nm and porosity 10 ± 0.5% reaches up to 0.21 (pF/RH%).

UO2 micron scale specimen fracture: Parameter identification and influence of porosities

Bending of micron-scale cantilevers with or without initial notch is simulated by finite element and their fracture is assessed using either the coupled criterion or a cohesive zone model. The fracture toughness and strength of UO2 single grain specimens with several crystal orientations are determined by means of inverse identification based on experimental tests at the micron-scale. Irradiation causes a decrease in fracture toughness from around 10 J/m2 to around 5 J/m2, whereas the strength variation remains in the order of magnitude of the measurement uncertainty. Premature fracture may occur in presence of a pore provided it is located close enough to the specimen surface undergoing tension, the resulting failure force decreasing with increasing pore size. A network of small porosities located on the fracture surface induces a decrease in the failure force which magnitude mainly depends on the total surface fraction and on the porosity locations rather than on the porosity size.

Experimental and numerical analysis of the hydraulic and thermal performances of the gradually-varied porous volumetric solar receiver

A gradually-varied porous structure is designed to increase the thermal performance of the porous volumetric solar receiver. Based on the replica method and multilayer recoating technique, the silicon carbide porous ceramic with linear-changed geometrical parameters is fabricated. The performances of the uniform and gradually-varied porous volumetric solar receivers are studied by both experiment and numerical simulation. An optimization method combining genetic algorithm and computational fluid dynamics analysis is applied to determine the optimum porosity distribution. The results present that porous volumetric solar receiver with linear-changed geometrical parameters exhibits better thermal performance than the uniform porous volumetric solar receivers, especially when the thickness of the receiver is small. Larger porosity in the front is beneficial for increasing the solar radiation penetration depth, which limits the reflectance and thermal radiative losses. Smaller porosity in the rear traps more solar radiation and increases the convective heat transfer. When the receiver’s thickness is larger, the performance of the gradually-varied volumetric solar receiver is nearly identical to that of the uniform receiver with largest porosity. The double-layer configuration is found to be the optimized structure of the gradually-varied porous volumetric solar receiver. The thermal efficiency could be further improved using genetic algorithm with an 11 K increase of the outlet temperature.

Uranium release surrounding a single fracture in a uranium-rich reservoir under geologic carbon storage conditions

Though geologic carbon storage (GCS) is widely recognized as a promising strategy to reduce emissions of greenhouse gas (GHG), the potential for mobilization of radioactive uranium (U) from U-bearing minerals in deep subsurface due to CO2 injection remains a concern. In this study, supercritical CO2 and brine flowing through a fracture surrounded by reservoir rock containing uranium is simulated so as to study the potential of uranium release as a result of CO2 injection and the impact of various factors on total uranium release rate. Mineral compositions of the reservoir rock are from previously published literature, which mimics typical sandstone mineral compositions. The reservoir rock is assumed to have 2 × 10−4 vol% UO2 in solid phase. Simulation results show that CO2 injection induces UO2 dissolution, and both CO2 and mobilized uranium are able to migrate in both the fracture and the rock matrix surrounding the fracture. However, the released uranium concentration is quite low in a 60-day simulation period. Mineral dissolution causes a very small porosity increase surrounding the fracture in the simulation period. Sensitivity analysis shows that an increase of UO2 specific surface area and UO2 content in reservoir rock causes a significant increase in released uranium concentration. In other words, total uranium release rate is positively correlated with the specific surface area of UO2 and UO2 content in reservoir rock because the increase of specific surface area and UO2 content increases the total area of UO2 in contact with HCO3− and O2, which raises total uranium release rate. In summary, uranium release in and surrounding the fracture is mainly controlled by uranium supply of the reservoir rock, and the risk of environmental contamination by CO2-induced uranium release is quite low in the scenario reported.

Improved alumina transparency achieved by high-pressure spark plasma sintering of commercial powder

Depending on starting powder and sintering conditions, alumina with extremely small grains and low residual porosity can be highly transparent. Combined with its excellent mechanical, thermal and chemical properties, transparent alumina is a promising material for a wide range of optical applications. In the present study, highly transparent alumina was fabricated by single-step high-pressure spark plasma sintering (HP-SPS) using raw commercial pure powder. The microstructure of the sintered alumina consists of fine grains with average size of ~170 nm and extremely fine residual porosity. The measured real in-line transmittance (RIT) was 72.6% at a wavelength of 640 nm, close to the calculated theoretical value (74.9%). The difference between theoretical and measured RIT was attributed to scattering by fine residual pores. This conclusion was supported by porosity analysis, and RIT calculations suggest that the porosity volume fraction is about 0.005%. The combination of fine grain size and high level of transparency could be suitable for potential advanced alumina-based laser materials.

Laboratory investigation of the properties of cement fly ash gravel for use as a column-supported embankment

Deep cement mixing (DCM) columns are used to support embankments built on soft clay, but these columns have limitations in terms of their engineering properties such as low column strength and low column permeability. Therefore, the use of cement fly ash gravel (CFG) instead of DCM columns has been introduced. The objective of this paper is to present an experimental investigation of the properties of CFG. Gravels with sizes of 4.76 to 12.70 mm were mixed with ordinary Portland cement (OPC) Type 1 and fly ash (FA) to create CFG materials. OPC was partially replaced by FA at levels of 0 to 25% by weight of OPC. The engineering properties of the CFG materials were studied through the porosity, compressive strength, flexural strength, modulus of elasticity, and permeability coefficient after curing for 28, 50, and 90 days. The microstructures of the OPC-FA pastes were examined by using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Finally, preliminary guidelines for selecting a suitable porosity of CFG columns were proposed. Test results show that the porosity of the CFG materials ranged from 25.8 to 31.1% and affected the strength and permeability. The strength of CFG was 6 to 13 times greater than that of a DCM column, and the permeability of CFG was 9 to 17 mm/s, which was much higher than that of a DCM column, indicating that the use of a CFG column-supported embankment built on soft clay was more effective than the use of a DCM column in terms of the column bearing capacity and acceleration of consolidation settlement. The replacement of 15% of the OPC with FA exhibited the highest strength and smallest porosity because it provided the greatest amount of calcium silicate hydrate. Preliminary guidelines show that small-sized gravel with medium porosity is proper for generating column-supported embankments on soft clay to carry medium loads and to accelerate the consolidation process.

Gas-solid reaction pathway for chlorination of rare earth and actinide metals using hydrogen and chlorine gas

Hydriding and chlorination of buttons of metallic cerium have been tested as a head-end step to separating metal impurities from actinides. The objective was to achieve complete conversion to chlorides while maintaining high surface area via small particles and open porosity. Hydriding by reaction with 100% H2 gas at 573 K was successful at reducing cm-scale metal buttons into small particles/fragments. This step was followed by reaction with flowing 99.5% anhydrous Cl2 gas at temperatures ranging from 423 to 573 K for 60 min. In experiments reported here, up to 92% conversion to cerium chloride was achieved from reacting with the anhydrous chlorine gas. The final chloride product has high porosity coupled with small particle sizes (microns to 1600 μm), which makes it suitable for subsequent purification processes. Higher chlorine concentrations in the gas favor higher conversion to chloride. The optimal temperature to achieve high chlorination is 523 K. Oxygen is a minor impurity in the chlorine gas which appears to prevent complete chlorination from being achieved.

Experimental characterization on pore parameter and the irradiation absorption efficiency of a series SiC foam specimens

This paper experimentally analyzes the thermal performance of a volumetric solar receiver with a series pore structures of silicon carbide foam. Twelve silicon carbide foam specimens with various porosities and pore diameters were systematically tested on a lab-scale test platform. Three-dimensional temperature distribution, including irradiated surface temperature distribution and internal solid temperature, were obtained. Non-uniform temperature distribution on the irradiated surface and internal field, as well as the corresponding thermal efficiency under different working conditions, was analyzed. The results demonstrate that pore diameter has a more significant effect on thermal performance than porosity, as the characteristics of the specific surface area among the examined samples were mainly determined by pore diameter. For the detected solid temperatures, the highest exceeded 1000 °C without any damage to the porous structure, and the maximum mean outlet air temperature exceeded 544 °C. The thermal efficiencies of the samples with smaller pore diameter were markedly higher in most cases. The best thermal efficiency was 85.4%, which was obtained from the specimen with pore diameter of 2.27 mm and porosity of 0.663. Optimal geometric properties of SiC foam absorbers may be characterized by small pore diameter and high porosity, which can beneficial by both the advantage of uniform irradiation absorption and effective interphase convection. The experimental data presented in this paper can provide a clear reference for the theoretical model and engineering design.

The effect of morphology on the ozone-gas sensing properties of zinc oxide sputtered films

One of the main obstacles in the development and design of semiconductor gas sensors is our limited understanding of the practical mechanisms responsible for sensing. Although theoretical models describe the importance of morphology on the gas sensing properties of semiconductor films, a direct relation between structure size/morphology and gas detection has not been experimentally established. In this work, the Radio-Frequency Sputtering method was used to obtain zinc oxide thin films from ceramic and metallic targets. Remarkable differences in the nanostructure size were observed when distinct powers of deposition were used. The samples were deposited on platinum interdigitated electrodes and exposed to ozone to have their sensing behavior analyzed. The feature size and film porosity were studied taking into consideration the enhancement of sensor performance, while their band gaps showed no significant differences between films. It was found that sensors with small features and low porosity present low ozone sensitivity and fast responses, while highly porous films with large features exhibit low sensitivity and slow responses. The optimum sensing performance was found to be at the apparent maximized surface area, where the best ozone response was observed. Our results show that radio frequency sputtering can be considered a versatile deposition technique for the production of semiconductor gas sensors, since porosity, feature size, and therefore gas sensor sensitivity, can all be controlled through the sputtering parameters of a Zn metallic target followed by thermal oxidation.

Characterisation of a High-Performance Al–Zn–Mg–Cu Alloy Designed for Wire Arc Additive Manufacturing

Ever-increasing demands of industrial manufacturing regarding mechanical properties require the development of novel alloys designed towards the respective manufacturing process. Here, we consider wire arc additive manufacturing. To this end, Al alloys with additions of Zn, Mg and Cu have been designed considering the requirements of good mechanical properties and limited hot cracking susceptibility. The samples were produced using the cold metal transfer pulse advanced (CMT-PADV) technique, known for its ability to produce lower porosity parts with smaller grain size. After material simulations to determine the optimal heat treatment, the samples were solution heat treated, quenched and aged to enhance their mechanical performance. Chemical analysis, mechanical properties and microstructure evolution were evaluated using optical light microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray fluorescence analysis and X-ray radiography, as well as tensile, fatigue and hardness tests. The objective of this research was to evaluate in detail the mechanical properties and microstructure of the newly designed high-performance Al–Zn-based alloy before and after ageing heat treatment. The only defects found in the parts built under optimised conditions were small dispersed porosities, without any visible cracks or lack of fusion. Furthermore, the mechanical properties are superior to those of commercial 7xxx alloys and remarkably independent of the testing direction (parallel or perpendicular to the deposit beads). The presented analyses are very promising regarding additive manufacturing of high-strength aluminium alloys.

Flat-evaporator-type loop heat pipe with hydrophilic polytetrafluoroethylene porous membranes

This paper describes an experimental study of a flat-evaporator-type loop heat pipe (LHP) with wicks made from hydrophilic polytetrafluoroethylene (PTFE) porous membranes, which have small pore sizes but high porosity and permeability. To demonstrate the applicability of these membranes, the LHP was designed completely and fabricated, after which the performance was experimentally investigated under a 0.52 m anti-gravity condition at a constant heat sink temperature of 80 °C. Two types of membranes were used, possessing different pore diameters and permeabilities. The pore diameter and permeability of wick 1 were 0.44 µm and 2 × 10−14 m2, respectively, while wick 2 had a pore diameter and permeability of 1.40 µm and 5 × 10−14 m2, respectively. A special wick support was designed and fabricated to ensure contact between the wick and the groove fins and to prevent the shrinkage of the PTFE membranes. Pure water was used as the working fluid. The effect of the PTFE wick characteristics on the LHP thermal performance was investigated by measuring the temperature at each point and the compensation chamber pressure. The LHP achieved steady-state operation at heat loads up to 1000 W, with a minimum thermal resistance of 0.052 K/W. Wick 2, which had a larger pore size and higher permeability, exhibited better performance than wick 1. The LHP operating temperature decreased by 10 °C, and the thermal resistance decreased by approximately 20% between wick 1 and wick 2.

Pore structure and physical properties of sandy conglomerate reservoirs in the Xujiaweizi depression, northern Songliao Basin, China

Pore structure analysis is the basis of reservoir classification and exploitation, especially for tight reservoirs with complex pore throat systems. The sandy conglomerates in the Lower Cretaceous strata in northeastern China have attracted little attention from explorers in the past 50 years, but prospecting of promising tight gas reservoirs has recently begun in this area. Here, we report on the pore structure and physical properties of samples from the Shahezi Formation in the Xujiaweizi depression. Pore throat structure was investigated using thin section observations, scanning electron microscopy (SEM), high-pressure mercury injection (HPMI), and nuclear magnetic resonance (NMR). Regression analysis was used to analyze the correlation between the various pore structure parameters and the reservoir's physical properties. The results show that the pore types in the Shahezi sandy conglomerates are primarily dissolution pores with few inter-particle pores and micro-cracks. The pores are mostly less than 1 μm in radius, and the large pores are generally connected by tiny throats with radii of less than 0.1 μm. The Porapex and Porem values, which reveal the connected pore volume, were derived from the HPMI capillary pressure curve and the NMR T2 spectrum, respectively. The Porapex and Porem values are more strongly correlated with the reservoir's permeability than the other pore structure parameters, including the max throat radius (Rmax), the median radius (R50), the homogeneity coefficient (ϕ), the sorting parameter (Sp), the displacement pressure (Pd), and the mercury removal efficiency (Ew). Porapex and Porem account for only a small portion of the total pore volume (average of 37.1%) but contribute (average of 81.7%) to the permeability. By studying the microscopic and macroscopic characteristics, three typical pore structures were identified mainly based on Porapex and Porem. Type I reservoirs are characterized by relatively well connected inter-dissolution pores and high Porapex(>2.0), Porem(>2.0), and total porosity(>5.5%). Type III reservoirs show poor physical properties with some intercrystalline pores and small Porapex(<1.0), Porem(<1.0), and total porosity(<3.5%). Type II reservoirs are between type I and type III reservoirs. Favorable reservoirs (Type I and Type II) are located in the strata shallower than 4200 m.

Photocatalytic degradation of Reactive Blue 21 dye using ZnO nanoparticles: experiment, modelling, and sensitivity analysis

ABSTRACT This paper presents the photocatalysis, adsorption, and photolysis of C.I. Reactive Blue 21 dye using synthesized zinc oxide nanoparticles. The density, mean particle diameter, surface area, and porosity of the catalyst were 5550 kg/m3, 1.19 × 10−7, 16,830 m2/kg, and 0.08, respectively. The impact of catalyst mass per volume of solution (0.2–1.0 kg/m3) was experimentally investigated in terms of the percentage of dye degradation. Due to the small catalyst porosity, adsorption contributed little to overall degradation. However, the photolysis of the dye was around 12.5%, which occurred predominantly between 0 and 5 min. In the second part of the present study, the photocatalytic degradation of C.I. Reactive Blue 21 was modelled mathematically based on the mass conservation law in the solution and catalyst. The model had two adjustable variables: the convection mass transfer coefficient and the photocatalytic reaction rate constant. The model was solved numerically using the finite difference method and was validated with the experimental data. The validated model was employed to examine the impact of catalyst size and initial pollutant concentration on the photocatalytic degradation.

Lattice Boltzmann simulation of forced convection melting of a composite phase change material with heat dissipation through an open-ended channel

This paper performs a numerical analysis of time-dependent forced convection heat transfer in an open-ended straight channel filled with a metal structure and paraffin as a phase change material (PCM). The unsteady two-dimensional governing equations, based on the Darcy-Brinkmann-Forchheimer (DBF) model and the two-energy transport equations (i.e. local thermal non-equilibrium, LTNE) at the representative elementary volume (REV) scale in their dimensionless forms, have been simulated using the thermal single relaxation time (T-SRT) Lattice Boltzmann Method (LBM) with three distribution functions to handle the fluid, and temperatures of the fluid and solid phases. Effects of Reynolds number (100 ≤ Re ≤ 600), Eckert number (0 ≤ Ec ≤ 10), porosity (0.1 ≤ ɛ ≤ 0.8) on dynamic and thermal fields, entropy generation, and energy and exergy efficiencies of the considered system are examined. The relevance of these parameters is highlighted and discussed during the charging (melting) and discharging (solidifying) processes. Interestingly, it can be stated that small porosities promptly accelerate these two processes due to high thermal conductivity of the metal foam/PCM composite, and improve energy and exergy efficiencies of the system, whatever Re for the very low porosity values (0.4 and 0.6). In addition, streamlines, isotherms and melt front (phase field) are exhibited for this parameters range. Based on the findings obtained, it is concluded that, in the context of laminar forced convection melting of a composite PCM with heat dissipation in a porous PCM-filled channel, 1) there is a critical Reynolds number for which the storage energy is optimal and whose quality is improved using both the porosity and the effects of viscous dissipation, and 2) the proposed approach's potential and the in-house code flexibility implemented are demonstrated.

Torsional vibration of the porous nanotube with an arbitrary cross-section based on couple stress theory under magnetic field

This article presented a solution for torsion vibration a nanotube made of pores material. Based on the porosity distribution, the material properties are assumed to vary according to a function along radius of nanotube. Moreover, the cross-section area of nanotube varied in the longitudinal direction by nonlinear function. As for the torque effect of the axial magnetic field, the well-known Maxwell’s relation is used. Couple stress theory is employed to study the influence of small-scale on torsional vibration of nanotube. The Navier equation and boundary conditions of the size-dependent porous nanotube were derived by the Hamilton principle. These equations were solved by employing the generalized differential quadrature method. Comparison between the results of the present work with the other paper reveals the accuracy of this study. To the best of authors’ knowledge, so far all previous torsional vibration of nanotube address the case of ignoring porosity. The novelty of this work is to present a solution by taking into account the existence of porosity. Finally, numerical results are presented to study the small scale effect and porosity on the frequency of the porous nanotube.

Microstructure and tribological properties of in-situ synthesized TiC reinforced reactive plasma sprayed Co-based coatings

In this study, TiC in-situ reinforced Co-based composite coatings (Co–TiC) were fabricated by reactive plasma spraying using Ti-graphite and Co-based alloy powders. The microstructure, mechanical and tribological properties were investigated. The hardness and tribological properties were measured by Vickers indenter and circular sliding tester. Si3N4 was used as friction counterpart, the sliding speed was 400r/min, the normal load was 30 N, and the sliding time was 30min. The results showed that Co–TiC coatings consisted of TiC, α-Co, Fe3Ni3B, Ni31Si12 and TiO2 phases. TiC phase was formed by the reaction between Ti and C directly. With the increase of Ti-graphite powders addition, more TiC was synthesized in-situ. The in-situ formed TiC enhanced the hardness and wear resistance of the coatings, coupling with forming small porosities (<9%). The highest hardness was 1035HV0.2 for Co–15TiC, which is about 20% higher than that of Co coating. The lowest wear volume was 0.0745 mm3 for Co–15TiC coating, which is just 13% of that of Co coating. The main wear mechanism of Co–TiC coatings in the present sliding test was abrasive wear.

Unveiling the effect of homogenization degree on electrochemical performance of TEMPO-mediated oxidized cellulose separators for lithium-ion batteries

Separator is an essential component for lithium-ion batteries, subtly providing transporting micro-channels for lithium ions and electric insulation between electrodes. In this paper, bleached eucalyptus cellulose pulp is implanted with TEMPO-mediated oxidization and high-pressure homogenization to attain cellulose pulps with both micro- and nano-sized fibers, where the blending ratio is regulated by homogenization times. Then the cellulose pulp is formed into separators through vacuum filtration after uniformly dispersed. Macro-properties, micro-structures, physical properties and electrochemical performance of the cellulosic separators are characterized and analyzed. And t commercial Celgard 2500 polypropylene separator is also investigated as comparison. The influence of homogenizing degree on comprehensive properties of the separators is investigated. Besides, the relationship between micro-structure and electrochemical performance is detailedly discussed. Results show that higher homogenization degree contributes to more nano-sized fibers and less micro-fibers, resulting in smaller porosity, poorer electrolyte uptake and larger contact angle. The nano-sized fibers are effective in promoting mechanical strength of separators, but are negative to the impedance performance. This study has unveiled the impact of high-pressure homogenization on the performance of separators, providing meaningful instruction for further development of qualified cellulose separators.