Water Adsorption Rate Research Articles

Polycaprolactone/gelatin-QAS/bioglass nanofibres accelerate diabetic chronic wound healing by improving dysfunction of fibroblasts

Worldwide, more than 25 % of patients with diabetes develop chronic diabetic wounds in their lifetime. Infection and dysfunctional fibroblasts represent two significant etiological factors contributing to impaired wound healing in patients with diabetes. It is therefore evident that the development of wound dressings with both anti-infective and DM fibroblast modulating functions has the potential for clinical applications. In this study, a PCL/gelatine-quaternary ammonium salts (QAS)/bioglass (BG) electrospun nanofibrous membrane was developed with physico-chemical and biological properties that not only meet the clinical requirements for wound dressings but also exhibit remarkable moisturising (water adsorption rate of 382.39 ± 4.36 %) and tear-resistance properties (a tear strength of ~5.5 MPa). The incorporation of QAS and BG has enhanced the biocompatibility and bioactivity of the nanofibres, while also imparting remarkable antimicrobial properties. The antibacterial efficacy of PGQ-BG against E. coli and S. aureus was found to be 92.8 ± 0.78 % and 99.3 ± 0.55 %, respectively. Moreover, it was demonstrated that PGQ-BG nanofibers exerted a promoting effect on the extracellular matrix (ECM) in dysfunctional fibroblasts and upregulated the expression level of α-smooth muscle actin (α-SMA), a marker of their differentiation to myofibroblasts in vitro and in vivo. Furthermore, the COL-III/COL-I ratio was significantly increased, indicating that PGQ-BG may also accelerate wound healing. The nanofibrous dressing reduced scar formation by increasing the COL-III/COL-I ratio. This is the first report of BG improving fibroblast dysfunction via COL-III and COL-I promotion in fibroblasts, both in vitro and in vivo. Therefore, this novel bioactive nanofibrous dressing represents an effective and safe therapeutic strategy for improving chronic wound healing in patients with diabetes.

Synthesis of customized zeolite X with outstanding CO2 selectivity over CH4 and N2 using facile activated spent fluid catalytic cracking catalysts

Efficient separation of CO2 from natural gas mixtures (CO2/CH4) and flue gas (CO2/N2) is pivotal for effective carbon capture and sequestration. Utilizing adsorbents derived from solid waste provides additional benefit for the carbon capture industry. This study introduces a convenient activation method at 200 °C for SFCC. Utilizing the activated SFCC as raw material under mild hydrothermal conditions, highly crystalline zeolite X (referred to as SFCC-X-200) of commercial quality with exceptional CO2 separation ability from CH4 and N2 is obtained. The static water adsorption rate of SFCC-X-200 meets the requirements of the national standard for commercial zeolite X (GB6287-86). Moreover, the ideal adsorbed solution theory (IAST) selectivity of SFCC-X-200 for CO2 from CO2/N2 (15/85, v/v) and CO2/CH4 (50/50, v/v) mixtures is significantly higher, at 797 and 199, respectively, compared to commercial X zeolite. SFCC-X-200 demonstrates tremendous potential for separating CO2/N2 and CO2/CH4 mixtures due to its outstanding adsorption capacity and selectivity, rapid attainment of adsorption equilibrium, complete desorption at ambient temperature, and extremely low cost.

Understanding the role of calcium silicate slag in sodium carbonate-activated green materials: Influence on kinetics, strength, and efflorescence

This study assessed the impact of calcium silicate slag (CSS), an industrial by-product of aluminum extraction from fly ash, on the reaction kinetics, compressive strength, and efflorescence of one-part sodium carbonate-activated slag (SCS). Various proportions of CSS (0%, 10%, and 20%) were used to substitute for slag. The resulting performances were evaluated through chemical shrinkage, heat liberation, compressive strength, water absorption, phase composition (XRD and TG.), microstructures (BET and BSE-EDS), and simulated efflorescence test (partially and fully immersed in deionized water). The results indicate that the CSS possesses a porous structure. The addition of CSS impairs flowability but accelerates the development of chemical shrinkage and heat liberation. The incorporation of CSS promotes the transformation of gaylussite, leading to an increase in CASH and hydrotalcite formation. Consequently, a higher compressive strength and a lower water adsorption rate are achieved. 10% CSS addition improves the splitting tensile strength of SCS under conditions of partial immersion in the efflorescence test. However, a 20% CSS substitution exacerbates the formation of efflorescence products and reduces the splitting tensile strength. These observations are associated with residual alkalis in CSS, a lower Al/Si ratio of products, and an increase in capillary pores attributed to CSS particles. This paper demonstrates the feasibility of using alkaline solid waste for slag substitution and performance regulation in SCS and reveals the underlying mechanism. The prepared CSS-SCS binder exhibits much lower energy consumption and CO2 emission than traditional cement-based material, as determined by life cycle assessment.

Changes in Intergranular Air Properties and Chemical Parameters of Short-term Stored Bulk Shelled Corn with Slightly High Moisture Content

Objective: This study is to determine the main parameters influencing the storage of shelled corn with slightly high moisture content (MC) so that its quality can be maintained. Methods: The intergranular air properties and chemical changes was determined in 4,169 tonnes of shelled corn bulk with an average MC of 15.3% and a height of 5m, which was stored for 90 days in a large warehouse in Shandong Province, China, from winter to early spring. The intergranular air property parameters were calculated with self-compiled software. Results: Fans were used to achieve temperature-equalizing aeration at a low rate (5.87m3/h/t) after warehousing, which decreased the bulk temperature from 6.8 to 4.7℃. Afterwards, with the increase in ambient temperature, the surface-layer grain temperature increased drastically, while that of the bottom layer increased slowly and those of the middle layers increased even more slowly. The minimum and mean cumulative dry-bulb, wet-bulb and dew-point temperatures (DPT) increased in the order of middle layer˂ bottom layer˂ surface layer. Free fatty acid content, kernel breakage percentage, water adsorption rate, gelatinization enthalpy, peak enthalpy, and fatty acid profiles (C16:0, C18:0, C18:3n3, C20:0 and C20:1) were significantly related to the cumulative intergranular air properties of grain bulk. Conclusion: The above physio-chemical parameters were significantly influenced by the minimum and mean cumulative values of relative humidity, Humidity ratio and DPT in the bulk, and can be used to evaluate the quality of shelled corn with slightly high MC during short-term storage.

Evaluation of Polyurethane Foam Derived from the Liquefied Driftwood Approaching for Untapped Biomass

Nowadays, climate change has become a serious concern, and more attention has been drawn to utilizing biomass sources instead of fossil sources and how petroleum chemical plastics should be reduced or replaced with bio-based materials. In this study, the optimized condition of liquefaction of driftwood was examined. There was a concern that driftwood might have some decay and chemical change. However, according to the Organic Micro Element Analyzer (CHN analyzer) test and Klason lignin and Wise methods, the results proved that lignin content (37.5%), holocellulose content (66.9%), and CHN compositions were very similar to regular wood. The lowest residue content of bio-polyols was produced using liquefaction conditions of 150 °C, reaction time of 180 min, catalyst content of 10%w/w, and 12.5%w/w driftwood loading. Polyurethane foam (PUF) derived from the liquefaction of driftwood and bio-based cyanate was prepared. The PUF prepared from the liquefaction of the driftwood exhibited slightly decreased thermal durability but was superior in terms of 3-time faster biodegradation and 2.8-time increased water adsorption rate compared to pure petroleum-based PUF. As a result, it was shown that driftwood can be identified as a biomass resource for biodegradable PUF.

Effects of re-dispersible latex powder-basalt fibers on the properties and pore structure of lightweight foamed concrete

In order to diminish global energy consumption and environmental pollution, the use of green building materials for construction has been noticeably popularized. In the present study, the use of re-dispersible latex powder-basalt fibers to prepare foamed concrete to improve the performance of foamed concrete has been assessed. The effects of basalt fibers and re-dispersible latex powder on the dry and wet densities, water adsorption rate, compressive strength, and microstructure of the foamed concrete, were then studied. The hydration products and pore structure were analyzed by X-ray diffraction (XRD) spectroscopy and scanning electron microscopy (SEM). The results revealed that basalt fibers slightly affected the density and water adsorption rate. With the increase in the content of re-dispersible latex powder, the wet density of the specimen increased, the dry density decreased, the difference between dry density and wet density increased, and the water adsorption rate decreased. With the addition of a re-dispersible latex powder, the pore size decreased, the pore structure density increased, and the effective pore number was elevated. Furthermore, the compressive strength of double-doped re-dispersible latex powder-basalt fibers was higher than that of single-doped basalt fibers. The XRD analysis of the hydration products and the SEM analysis of the microstructures confirmed that the re-dispersible latex powder formed new hydration products after hydration. These hydration products gathered on the foam surface and became fused to form a film. Also, the polymer membrane interweaves with the hydration products to form a continuous network. The basalt fibers were evenly distributed in the internal structure, penetrated the polymer membrane, and formed a three-dimensional random network system. The random network system could support the bubbles and had the effect of secondary reinforcement. Moreover, the interfacial adhesive force between the fibers and the polymer film dispersed a part of the energy and produced a more continuous and uniform stress field in the structure.

A universal strategy for efficient synthesis of Zr‐based MOF nanoparticles for enhanced water adsorption

AbstractZr‐based metal‐organic framework (Zr‐MOF) nanoparticles (NPs) have attracted extensive research thanks to their outstanding thermal and chemical stability, but their efficient synthesis is still challenging. Here, high‐quality Zr‐MOF NPs with tunable and uniform particle sizes can be successfully fabricated within 30 min by high‐gravity technology with high yields. Significantly, the rapidly milder preparation of UiO‐66 NPs can also be achieved at 90 or 70°C. This strategy has been extended to the synthesis of other Zr‐MOF NPs. Furthermore, the water vapor adsorption properties of obtained UiO‐66 NPs display a size‐dependent effect. The 70 nm UiO‐66 NPs have the highest adsorption capacity of 625 mg g−1 among unmodified UiO‐66 reported so far, and manifest 2.0–2.8 times faster water adsorption rate than the micron ones. This study provides a feasible method for the efficient and mild preparation of MOFs nanoparticles, which may promote the synthesis and applications of nano‐sized MOFs.

In-situ CBM3-modified bacterial cellulose film with improved mechanical properties

Cellulose materials have poor wet strength and are susceptible to acidic or basic environments. Herein, we developed a facile strategy to modify bacterial cellulose (BC) with a genetically engineered Family 3 Carbohydrate-Binding Module (CBM3). To assess the effect of BC films, water adsorption rate (WAR), water holding capacity (WHC), water contact angle (WCA), and mechanical and barrier properties were determined. The results showed that CBM3-modified BC film exhibited significant strength and ductility improvement, reflecting improved mechanical properties of the film. The excellent wet strength (both in the acidic and basic environment), bursting strength, and folding endurance of CBM3-BC films were due to the strong interaction between CBM3 and fiber. The toughness of CBM3-BC films reached 7.9, 28.0, 13.3, and 13.6 MJ/m3, which were 6.1, 1.3, 1.4, and 3.0 folds over the control for conditions of dry, wet, acidic, and basic, respectively. In addition, its gas permeability was reduced by 74.3 %, and folding times increased by 56.8 % compared with the control. The synthesized CBM3-BC films may hold promise for future applications in food packaging, paper straw, battery separator, and other fields. Finally, the in situ modification strategy used to BC can be successfully applied in other functional modifications for BC materials.

Enhanced Water Adsorption of MIL-101(Cr) by Metal-Organic Polyhedral Encapsulation for Adsorption Cooling

Metal-organic frameworks (MOFs) are one of the most promising adsorbents in the adsorption cooling system (ACS) for their outstanding water adsorption performance. Notwithstanding that fact, numerous reports pay more attention to the ACS performance improvement through enhancing equilibrium water uptake of MOFs. However, adsorption cooling performance, including specific cooling power (SCP) and coefficient of performance for cooling (COPC) of MOF/water working pairs, always depends on the water adsorption kinetics of MOFs in ACS. In this work, to increase the water adsorption rate, the preparation of MOP/MIL-101(Cr) was achieved by encapsulating hydrophilic metal-organic polyhedral (MOP) into MIL-101(Cr). It was found that the hydrophilicity of MOP/MIL-101(Cr) was enhanced upon hydrophilic MOP3 encapsulation, resulting in a remarkable improvement in water adsorption rates. Furthermore, both SCP and COPC for MOP/MIL-101(Cr)-water working pairs were also improved because of the fast water adsorption of MOP/MIL-101(Cr). In brief, an effective approach to enhance the water adsorption rate and cooling performance of MOF-water working pairs through enhancing the hydrophilicity of MOFs by encapsulating MOP into MOFs was reported in this work, which provides a new strategy for broadening the application of MOF composites in ACS.

Improved adsorption cooling performance of MIL-101(Cr)/GO composites by tuning the water adsorption rate

Incorporation of MIL-101(Cr) with graphene oxide (GO) improves the water adsorption rate, leading to enhanced adsorption cooling performance including SCP and COPC.

High‐Density Frustrated Lewis Pair for High‐Performance Hydrogen Evolution

AbstractIt is significant to develop catalysts with high‐density and adjacent frustrated Lewis pair (FLP) sites. Herein, a method is designed to construct FLPs on an intermetallic alloy (IMA) with regulable acidity and basicity by using the Mott–Schottky effect. By dint of the high‐density FLP site and suitable acidity and basicity on IMA, the fct‐PtCo@NC displays excellent hydrogen evolution reaction performance. The catalyst fct‐PtCo@NC, with high‐density FLP sites, exhibits a fast water adsorption and decomposition rate, which is derived from the synergistic effect of FLP‐acid sites and FLP‐base sites significantly reducing the energy barrier between the two processes. Due to the FLP‐base Pt site, fct‐PtCo@NC has the best binding energy of hydrogen intermediates, the H3O+ generated during the reaction can accumulate on it and form an acid‐like environment, and thus speed up the kinetics of the reaction. In comparison, the catalyst without FLP shows lower binding energy and the formation of H3O+ is not observed. This work opens a new horizon for the design of new‐style heterogeneous FLP catalysts and the catalysts with high‐density and adjacent FLP sites are expected to be used in a variety of multistep catalytic reactions.

Simulation Study on the Screening of Hydrophobic Surface Materials for Pipeline Drag Reduction Based on Adsorption Properties.

Hydrophobic surface drag reduction techniques are effective in reducing the frictional resistance of fluids, the adsorption of liquid molecules on hydrophobic surfaces can reflect the resistance to fluid flow through such solid surfaces. Based on molecular simulation technology, we investigate the adsorption characteristics of water molecules on hydrophobic surfaces to achieve rapid screening of hydrophobic materials in fire-fighting water supply systems. The Monte Carlo method was used to simulate the adsorption process of polymers and to analyze the effects of temperature and fixed adsorption quantity. Contact angle tests were also done to verify polymer hydrophobicity. The isothermal adsorption heat, water molecule distribution, and energy distribution were studied by molecular mechanics and molecular dynamics methods. Then, adsorption localization simulations and electrostatic potential distributions were used to predict possible adsorption sites on hydrophobic surfaces and single-molecule chains. Finally, the interaction energy, diffusion coefficient, and free volume were investigated to explain the adsorption mechanism at the molecular level. Simulation results show that, overall, PTFE was more hydrophobic and PES was more hydrophilic and at 298 K, the number of adsorbed water molecules was ranked as follows: PTFE < PVDF < PVC < PMMA < PPS < CSM < BD-HDI < BD-MDI < BD-TDI < PES. Furthermore, PTFE, PVDF, PVC, PES, and PPS have more stable adsorption configurations on the (0 -1 0) surface. According to the findings, hydrogen bonding dominates the interaction between water molecules and hydrophilic polymers, whereas π-π interactions increase water molecules' diffusion resistance in polymers with benzene rings. In addition, PES contains many sulfone groups and ether bonds, which disorganize the chain arrangement to provide more free volume, whereas the water adsorption rate of PTFE is reduced because its molecular chains are less convoluted and more organized.

Investigation on water vapor adsorption performance of carbon based composite adsorption material ACF-silica sol-LiCl

The composite adsorption material ACF-silica sol-LiCl (ASL) is prepared by impregnating activated carbon fiber (ACF) with silica sol and LiCl to improve the water vapor adsorption performance. The silica sol provides support to the soft ACF and solidifies it. The silica sol also increases the adhesion area in the ACF for the LiCl. The LiCl can effectively improve the water vapor adsorption performance of the ACF. The adsorption performance of the ASL is optimum when the LiCl impregnation concentration is 430 mg/L. Scanning electron microscope images show that the silica sol and LiCl fill the fibers pores and spaces between the fibers in the ACF after impregnation. And adsorption kinetics of the ASL is characterized using a linear driving force (LDF) model and experiments. Results show that ASL has a high dynamic water absorption rate and adsorption rate coefficient (k). The k of the ASL reaches 1.58 × 10−4−2.05 × 10−4, which is 0.27 × 10−4−0.59 × 10−4 higher than that of the ACF. Meanwhile, the results of water vapor isothermal adsorption tests show that the impregnation of silica sol and LiCl increases the hydrophilicity of the ACF, and thus greatly enhances its water vapor adsorption capacity. The adsorption capacity of the ACF is almost 0 at P/P0 < 0.2 and reaches a maximum of 0.5479 g/g at P/P0 = 0.65. The adsorption capacity of the ASL steadily increases with the relative pressure. When the relative pressure is close to 1, the adsorption capacity of the ASL reaches 2.2876 g/g, which is 2.67 times the maximum for the ACF.

Non-Microplastic Microbeads From Sago Liquid Waste With The Addition Of Chitosan as Antibacterial Function: A Review

Plastic has many advantages due to flexibility, unaffordable, transparent, and toughness. Plastics can size into small sizes (microplastics) or large sizes (macroplastics). Microbeads are granules of plastic or fiber that can often be utilized in many personal care products with sizes below 1 mm. These size of microbeads affect to environmental. Microbeads cannot be filtered by the sewage treatment system resulting microbeads go through to end up in water bodies and become a dangerous pollutant. Therefore any efforts must be conducted to replace the use of plastics microbeads. The microbeads can be prepared from with organic materials having easily degradation with stand the same functions. One of the ways can be accomplished through preparation of bacterial cellulose from sago waste since liquid waste can be used to produce bacterial cellulose. Bacterial cellulose is highly potential to be developed into microbeads as it has advantages of high purity, good tissue structure, high degradation ability, mechanical strength, and easy degradability. The utilization of sago liquid waste is very beneficial because it can reduce environmental pollution and production costs. Additionally, antibacterial properties in microbeads can introduce chitosan, eucalyptus filtrate, celery leaf extract, basil, and cinnamon. The use of chitosan as an additive in the preparation of microbeads will reduce the rate of water adsorption, improve mechanical properties, and reduce the moisture in the microbeads that would promote the ability of microbeads to against bacteria.

Biodegradable Films from Spray Dried Starch Inclusion Complexes with Bioactive Compounds—The Effect of Glycerol and pH

AbstractIn the present study, thermoplastic films are prepared using spray dried starch‐bioactive compound systems powders with different concentrations of glycerol (20% or 40%). The starch‐based films are produced by casting after dissolution under neutral (pH 7) or alkaline conditions (pH 12). Results reveal that elevated glycerol contents lead to increased moisture and hygroscopicity which is related to the availability of more ─OH groups. ANOVA shows that the glycerol concentration, the pH value, and the interactions of bioactive compounds with glycerol, bioactive compounds with pH, and glycerol with pH, influence significantly the mechanical properties of the thermoplastic starch films. Young's modulus of elasticity increases alongside with glycerol content, indicating improved flexibility of the films. Stress decreases with higher glycerol contents and lower pH while strain on the contrary, increases as the glycerol and pH increase in the films. Significant differences are also observed in water adsorption and water vapor transmission rate values. As expected, water adsorption increases with increasing relative humidity (RH) with the glycerol content positively affecting the water uptake by the films. Microscopic examination indicates the homogeneous distribution of the bioactive compounds in the matrix of the films.

Assessment of Alkali-Silica Reaction Potential in Aggregates from Iran and Australia Using Thin-Section Petrography and Expansion Testing.

The alkali–silica reaction can shorten concrete life due to expansive pressure build-up caused by reaction by-products, resulting in cracking. Understanding the role of the aggregate, as the main reactive component, is essential for understanding the underlying mechanisms of the alkali–silica reaction and thereby reducing, or even preventing, any potential damage. The present study aims to investigate the role of petrographic studies along with accelerated tests in predicting and determining the potential reactivity of aggregates, including granite, rhyodacite, limestone, and dolomite, with different geological characteristics in concrete. This study was performed under accelerated conditions in accordance with the ASTM C1260 and ASTM C1293 test methods. The extent of the alkali–silica reaction was assessed using a range of microanalysis techniques including optical microscopy, scanning electron microscopy, energy-dispersive X-ray analysis, and X-ray powder diffraction. The results showed that a calcium-rich aggregate with only a small quantity of siliceous component but with a higher porosity and water adsorption rate can lead to degradation due to the alkali–silica reaction, while dolomite aggregate, which is commonly considered a reactive aggregate, showed no considerable expansion during the conducted tests. The results also showed that rhyodacite samples, due to their glassy texture, the existence of strained quartz and quartz with undulatory extinction, as well as the presence of weathering minerals, have a higher alkali-reactivity potential than granite samples.

Experimental study on the influence of wetting agent addition on the water adsorption and impact crushing dust generation of coal

AbstractThis study is aimed at investigating the influence of wetting agent addition on the water adsorption capacity, dust generation capacity and dust particle size distribution of coal. To achieve this aim, nonylphenol ethoxylate 10 wetting agent was used as an additive to prepare a 0.1% concentration solution, and a comparative test was conducted on different coal types from three coal mines in different provinces. The test results suggest that the natural saturated water adsorption time of coal was shortened by 33%–67% through wetting agent addition. Therefore, wetting agents are effective for enhancing water injection operations that require a limited construction period. The influence of wetting agent addition on the saturated water adsorption amount differed significantly for different coal types, and the wetting agent did not generally improve the saturated water adsorption rate. However, wetting agent addition alone did not lower the dust generation rate from coal. For a given moisture content, the wetting agent influenced the particle size distribution of dust generated during impact crushing differently between types of coal. For the three coal types investigated, wetting agent addition reduced the concentration of airborne by up to 8%.

Mechanically Strong, Hydrostable, and Biodegradable Starch–Cellulose Composite Materials for Tableware

AbstractThe extensive use of nondegradable plastic tableware has brought serious environmental problems. Starch‐based materials are good alternatives to plastics, but poor mechanical properties and intrinsic hydrophilicity limit their utilizations. In order to address this issue, naturally abundant bagasse pulp fiber is used as the reinforcing agent to improve the mechanical properties of starch and polydimethylsiloxane coating (CSB35‐PDMS50) to improve their hydrophobicity and hydrostability. CSB35‐PDMS50 reaches the tensile strength of 21.2 MPa and contact angle of 121°. The enhancement of the mechanical strength can be explained by strong hydrogen bonding between starch and cellulose, as indicated by noncovalent interaction‐reduced density gradient (NCI‐RDG) analysis. CSB35‐PDMS50 retains the low water adsorption rate within 60 h, remains stable in water for 24 h without morphology change, and maintains initial hydrophobicity after continuous abrasion in sandpaper and high‐pressure water spraying due to the formation of Si─O–C bonds. The water absorption capacity of CSB35‐PDMS50 is less than 10% when used as the cap materials for Eppendorf tube for 30 days. Furthermore, CSB35‐PDMS50 demonstrates good biodegradability in the soil with 74% in 100 days. The tableware prepared from ther composites demonstrates good potentials as the competitive substitute for plastics with easy production, high strength, and biodegradability.

Design of Organic-Free Superhydrophobic TiO2 with Ultraviolet Stability or Ultraviolet-Induced Switchable Wettability.

Superhydrophobic TiO2 with great application potential is mainly obtained by surface modification with low surface energy organics, which is easily degraded under sunlight irradiation, which results in the loss of superhydrophobic properties. Herein, we developed a room-temperature pulsed chemical vapor deposition (pulsed CVD) method to develop amorphous TiO2-deposited TiO2 nanoparticles. The ultraviolet stability/ultraviolet-induced reversible wettability switch had been simultaneously realized by different and controllable deposition cycles of amorphous TiO2. The superhydrophobic properties of the organic-free TiO2 were determined by the micrometer-nanometer-sub-nanometer multiscale structure, the multiscale pore structure, and the large Young's contact angle resulting from carboxylic acid adsorption. Also, we found that the adsorption rate and adsorption stability of oxygen and water at the surface oxygen vacancies were the key to facilitate the reversible switching between superhydrophilic and superhydrophobic states, which was well demonstrated by experimental characterization and theoretical simulation. In addition, we also found that the resistance of dense amorphous TiO2 films on the TiO2 surface to the migration of photogenerated electrons and holes was the key to maintain the stable superhydrophobic properties of superhydrophobic TiO2 under ultraviolet illumination. The powders were strongly ground and the coating surface was rubbed on the surface of the sandpaper, which still maintained superhydrophobic properties, providing favorable conditions for the application of superhydrophobic TiO2. This work modulates the ultraviolet stability and dark/ultraviolet-induced switchable superhydrophobicity/superhydrophilicity of coated TiO2 by simply adjusting the number of deposition times in a pulsed CVD process for the first time, thus contributing to the development of organic-free superhydrophobic TiO2.

Enhanced thermal conductivity and adsorption rate of zeolite 13X adsorbent by compression-induced molding method for sorption thermal battery

Sorption thermal battery is an effective thermal energy storage technology for solar energy utilization and waste heat recovery. However, the low thermal conductivity and packing density of loose particle adsorbents are the common drawbacks for realizing high energy-density and power-density sorption thermal battery. Herein, we propose a compression-induced molding method for preparing high-performance modular adsorbents with high thermal conductivity and packing density by compacting loose particle adsorbents with tunable packing densities and thicknesses. The experimental results showed that the thermal conductivity and packing density of modular adsorbents can be enhanced by 3 times and 2 times, respectively, when compared to that of particle adsorbents. The water adsorption rate can be also improved by this method at an optimized compression pressure of 10 MPa and thickness of 2 mm. Furthermore, we constructed a sorption thermal battery by employing the modular adsorbents to realizing high-efficient thermal charging/discharging processes. The experimental results demonstrate the maximum volumetric power density is as high as 145 kW/m3 and the maximum volumetric energy density up to 75 kWh/m3, which are 1.61 times and 1.27 times higher than those of pristine particle adsorbent, respectively. Therefore, it is verified that the sorption thermal battery with modular adsorbent is more powerful and compact than using conventional particle adsorbent.