Mesopore Size Research Articles

Carbon sequestration in earth-based alkali-activated mortar: phase changes and performance after natural exposure

This research investigates the effect of carbon sequestration via accelerated carbon curing (ACC) in alkali-activated earth-based alkali-activated mortar (25S-AAM) on the long-term engineering performance, chemical bonding and microstructure. The addition of clay accelerates hydration kinetics and promotes the formation of more cross-linked calcium–(sodium) alumino silicate hydrates (N-A-S-H and C-(N)-A-S-H). This contributes to early strength and a 25% reduction in total shrinkage after 60 days. Although ACC promotes higher carbon sequestration and increases 1-d compressive strength by 13%, it leads to severe decalcification of 25S-AAM after 365 days of natural exposure, resulting in coarsening of the pore structure in the mesoporous size range of 10–100 nm. Due to a relatively low Ca/Si ratio, 25S-AAM is more adversely affected by natural carbonation during the 365-d exposure period than the control (without clay). In summary, ACC is not recommended for earth-based AAM products especially if they are applied for outdoor constructions.

Multiscale simulation of liquid chromatography: Effective diffusion in macro–mesoporous beds and the B-term of the plate height equation

We performed multiscale simulations of analyte sorption and diffusion in hierarchical porosity models of monolithic silica columns for reversed-phase liquid chromatography to investigate how the mean mesopore size of the chromatographic bed and the analyte-specific interaction with the chromatographic interface influence the analyte diffusivity at various length scales. The reproduced experimental conditions comprised the retention of six analyte compounds of low to moderate solute polarity on a silica-based, endcapped, C18 stationary phase with water‒acetonitrile and water–methanol mobile phases whose elution strength was varied via the volumetric solvent ratio. Detailed information about the analyte-specific interfacial dynamics received from molecular dynamics simulations was incorporated through appropriate linker schemes into Brownian dynamics diffusion simulations in three hierarchical porosity models received from physical reconstructions of silica monoliths with a mean macropore size of 1.23 µm and mean mesopore sizes of 12.3, 21.3, or 25.7 nm. The mean mesopore size was found to have a similar influence on the effective mesopore diffusivity as the analyte polarity and the mobile-phase elution strength, which together determine the analyte residence time on a column. A smaller mesopore size attenuated the increase of the effective mesopore diffusivity with increasing mobile-phase elution strength significantly. The effective bed diffusivity was limited by the analyte residence time rather than by morphological details of the mesopore space. The stronger an analyte was retained by the chromatographic interface inside the mesopores, the slower became the mass transfer between the pore space hierarchies and the lower was the effective bed diffusivity. The B-terms of the plate height equation were finally generated with the bed diffusivities and phase-based retention factors derived from the hierarchical porosity models using additional information about the stationary-phase limit obtained from the analysis of analyte–bonded phase contacts. The B-terms highlight analyte- and mobile phase-specific behavior relevant to isocratic and gradient elution conditions in chromatographic practice. In particular, U-shaped B-term curves are observed due to the dominating contribution of the retention factor and the bed diffusivity to the B-term at low and high elution strength of the mobile phase, respectively.

Synthesis, Characterization and Electrochemical Performance of Bi2S3/Rice Husk-Based Activated Carbon Composites As Lithium Ion Battery Anodes

This study investigates the impact of hydrothermal duration on bismuth sulfide/activated carbon composites (Bi2S3/AC) by varying the duration to 8, 24, and 48 hours. The primary aim is to delineate the composite characteristics and electrochemical performance of Bi2S3/AC composites, aiming to produce anodes for lithium-ion batteries with high capacity, excellent cyclic stability, and minimal volume expansion. Activated carbon derived from rice husks was synthesized via a carbonization process and chemical activation using H3PO4 as an activator. Subsequently, the synthesis of Bi2S3/AC composites used bismuth nitrate pentahydrate and thiourea precursors through the hydrothermal method that involved three variations of hydrothermal duration: 8, 24, and 48 hours, denoted as BC8, BC24, and BC48, respectively. The FTIR test indicates the presence of Bi-S, C=C, and C-O groups in the three composite products, signifying the existence of bismuth sulfide and activated carbon. The XRD result reveals orthorhombic crystal forms in the composites, while the SEM-EDX mapping illustrates particle morphologies resembling flower-like shapes. These compositions comprise Bi 74.16%, S 11.37%, and C 10.43%. The GSA test suggests a mesoporous pore size in these composites. In final result, BC24 exhibits the highest electrical and ionic conductivity, measuring 2.12 × 10−3 S.cm−1 and 2.057 × 10−4 S.cm−1, respectively. The CV data of the BC24 composite indicates two reduction and oxidation peaks in the first cycle. Charge-discharge test on the BC24 composite exhibits a specific charge capacity of 445.51 mAh/g and a discharge capacity of 364.24 mAh/g.

Improvement of Mesoporous Carbon Supports for PEFC

New mesoporous carbon (MC) bulk was developed and used as a cathode support, and then 45% Pt/new MC cathode was prepared. Current-voltage (IV) performance of a membrane electrode assembly (MEA) with 45% Pt/new MC cathode was much improved at the high current density area in comparison to a MEA with 33% Pt/conventional MC and also to a standard MEA. Reasons for this improvement were considered in this study. The increased ionomer/carbon (I/C) ratio in the cathode layer was found to be one of the factors for improving IV performance. Also, increase in Pt loading percent against the carbon support came to another factor, which lead to a thinner catalyst layer followed by reducing activation overvoltage and diffusion overvoltage. However, the most important factor for the improvement in the high current density area was found to be most likely the size of mesopores.

Improvement of Mesoporous Carbon Supports for PEFC

New mesoporous carbon (MC) bulk was developed and used as a cathode support, and then 45% Pt/new MC cathode was prepared. Current-voltage (IV) performance of a membrane electrode assembly (MEA) with 45% Pt/new MC cathode was much improved at the high current density area in comparison to a MEA with 33% Pt/conventional MC and also to a standard MEA. Reasons for this improvement were considered in this study. The increased ionomer/carbon (I/C) ratio in the cathode layer was found to be one of the factors for improving IV performance. Also, increase in Pt loading percent against the carbon support came to another factor, which lead to a thinner catalyst layer followed by reducing activation overvoltage and diffusion overvoltage. However, the most important factor for the improvement in the high current density area was found to be most likely the size of mesopores.

Unveiling the porosity effect of superbase ionic liquid-modified carbon sorbents in CO2 capture from air

Direct air capture (DAC) of CO2 represents one of the most promising technologies to achieve negative carbon emissions. In this work, the superbase ionic liquids (ILs)-modified carbon substrates were developed for DAC of CO2 by harnessing the strong CO2 binding capability of IL and the ordered porous channels of the carbon supports. Detailed porosity analysis revealed that the IL with an aromatic cation and an oxygenate anion preferred to fill the micropores, and a thin layer was created on the surface of the mesopores. Strong π-π interaction between the IL layer and the carbon surface was disclosed by wide-angle X-ray scattering (WAXS) analysis, leading to enhanced thermal stability of the IL phase. For the same lL coating amount, the DAC of CO2 evaluation revealed that a larger mesopore size and pore volume in the carbon/IL composite materials led to higher CO2 uptake capacity by exposing more active sites to integrate CO2 from diluted sources. The thermodynamic analysis confirmed the critical role of IL coating in providing strong chemisorption sites and significantly improved selectivity to enrich the diluted CO2 from the air atmosphere. This work provides guidance on leveraging the scaffolds' surface properties and porosities of the scaffolds to optimize DAC of CO2 behavior.

Mechanism of one-step hydrothermal nitric acid treatment for producing high adsorption capacity porous materials from coal gasification fine slag

The increasing amount of coal gasification fine slag (CGFS) necessitates its resource utilization. CGFS, mainly composed of porous carbonaceous particles and partially fused spherical or agglomerated ash particles, is an inexpensive and high-quality raw material for preparing adsorbent materials. However, the challenge remains in developing a simple, low-cost, and environmentally friendly method to produce high-performance porous materials from CGFS. In this study, a one-step treatment method using 2 mol/L nitric acid under hydrothermal conditions was proposed for CGFS. The adsorbent material (CGFS-2 M) prepared under a solid–liquid ratio of 2:5 and an initial concentration of 200 mg/L methylene blue (MB) exhibited an equilibrium adsorption capacity as high as 210.20 mg/g. The excellent adsorption performance of CGFS-2 M can be attributed to several factors: acid leaching for mineral removal and pore formation, resulting in a specific surface area and total pore volume 2.2 and 1.6 times that of untreated CGFS, respectively, and an optimized mesoporous pore size distribution favorable for MB adsorption; optimal mineral removal and a well-defined carbon microcrystal structure providing more space for MB adsorption; nitric acid treatment increasing the surface oxygen content and hydrophilicity, enhancing its ability to remove MB. The synergistic effect of pore structure improvement and surface modification indicates a feasible research direction for enhancing the performance of CGFS-based adsorbent materials. These results provide theoretical support for the development of efficient CGFS-based adsorbents.

Electrochemical Synthesis of Metal‐Organic Frameworks Based on Zinc(II) and Mixed Ligands Benzene‐1,4‐Dicarboxylate (BDC) and 4,4′‐Bipyridine (Bpy) and its Preliminary Study on CO2 Adsorption Capacities

AbstractEfficient and environmentally friendly synthesis methods for metal‐organic frameworks (MOFs) have emerged as a compelling topic in the organometallic field. In this study, we successfully electro‐synthesized a MOF based on mixed ligands, benzene‐1,4‐dicarboxylate (BDC) and 4,4′‐bipyridine (Bpy), denoted as MOF‐508b, and investigated its CO2 adsorption capacity, comparing it with that of Zn‐BDC and Zn‐Bpy coordination polymers. Unlike the circular shapes of Zn‐BDC and Zn‐Bpy, MOF‐508 adopts a three‐dimensional structure upon binding with the pillar ligand, featuring mesoporous pore sizes. MOF‐508b demonstrates superior stability at room temperature, exhibiting a thermal stability of 400 °C. The CO2 capture potential of the materials was assessed under low‐pressure conditions at room temperature. The pillared layer of MOF‐508b results in the reduction of open metal sites, facilitating the binding of active CO2 through coordination, thereby influencing its optimum CO2 adsorption capacity (2.51 mmol g−1), which was found to be lower than that of Zn‐Bpy (3.83 mmol g−1) and Zn‐BDC (4.46 mmol g−1). The adsorption mechanism on MOF‐508b follows the Weber‐Morris model, emphasizing diffusion within particles over direct attachment to the material surface.

Optimizing lignin demethylation using a novel proton- based ionic liquid: 1, 2-propanediamine/glycolic acid catalyst

Demethylation modification of lignin is an effective strategy to overcome the barrier to its high-value conversion. The purpose of this study focuses on the new proton-based ionic liquid (PIL) 1, 2-propanediamine/glycolic acid (PD/GA) as a catalyst and solvent to achieve the targeted oxidation of lignin. The PD/GA solvents have higher selectivity and efficiency. Optimal phenolic hydroxyl (PH)-increment was achieved, demonstrating enhanced demethylating effect on lignin by modulating the acid-base molar ratio, reaction temperature, and reaction time. Compared to ethanolamine/acetic acid (CE/AC) treatment, the PD/GA treatment at molar ratio 1.25, temperature 60 °C, and 3 h increased the PH-content from 37.74 to 59.91 %. Additionally, the lignin treated with PD/GA exhibited excellent recyclability, featuring a larger Brunauer-Emmett-Teller surface area (1.45 m2.g−1), total pore volume (9.51*10−3 cm3.g−1), and mesoporous size (26.15 nm). The treated lignin yielded maximum ultraviolet resistance and antioxidant activity. These results present new avenues for the development of green and efficient lignin demethylation methods.

Improved electrochromic device based on mesoporous TiO2 and NiO films

Fabrication of electrochromic films with micro/nanostructures is one of the most feasible ways to improve their properties for high-performance electrochromic devices (ECDs). In this work, mesoporous TiO2 and NiO electrochromic films are prepared by sol-gel technique with an auxiliary solvent of F108 (PEO[Formula: see text]PPO[Formula: see text]PEO[Formula: see text]). By adjusting the content of F108 and heat treatment temperature, the transparent and uniform mesoporous films are successfully prepared. The TiO2 and NiO films are composed of inter-connected nanoparticles with a size of about 20 nm. The thicknesses of the films are about 300 nm and the mesoporous sizes are about 13 nm. The films have a short response time during the electrochromic process. When supplied with positive/negative voltages for 50 s, the coloring/bleaching times of TiO2 and NiO mesoporous films are 15/13 and 17/12 s, respectively. The ECD fabricated with TiO2 and NiO mesoporous films shows good electrochromic properties: short response time (14/19 s, for bleaching/coloring time), wide transmittance modulation range ([Formula: see text]37.21% at 540 nm), high coloration efficiency (CE) (100.6 cm2/C at 540 nm) and outstanding cycle stability (800 cycles). These are attributed to the mesoporous channels of films, which can increase reaction activity site, shorten ions transport path, and thus improve electrochromic reaction.

Understanding retention and intra-particle diffusivity of alkylsulfobetaine-bonded Ethylene Bridged Particles with different mesopore sizes for hydrophilic interaction liquid chromatography applications

The role of the average pore diameter (APD) of 1.7μm AtlantisTM Premier BEHTM Particles derivatized with a zwitterionic group (propylsulfobetaine) on the efficiency of their 2.1 × 50 mm hydrophilic interaction liquid chromatography (HILIC) packed columns is investigated experimentally. Van Deemter plots for toluene (neutral, hydrophobic), cytosine (neutral, polar), tosylate (negatively charged), bretylium and atenolol (positively charged) were measured on three HILIC columns packed with BEH Z-HILIC Particles having APDs of 95 Å, 130 Å, and 300 Å. The intraparticle diffusivities of the analytes across these three BEH Z-HILIC Particles were measured by the peak parking method.The experimental data reveal that the slope of the C-branch of the van Deemter plots can be reduced by factors of about 15 for toluene, 2.5 for cytosine, 6 for atenolol, 5 for tosylate, and 14 for bretylium with increasing the APD from 95 Å to 300 Å. This observation is explained by: (1) the reduced amount of the highly viscous water diffuse layer and subsequent increase of the amount of acetonitrile-rich eluent in the mesopores, (2) the localized electrostatic adsorption of the retained analytes onto the zwitterion-bonded BEH Particles, and (3) depletion/excess of the analytes into the water diffuse layer. A general model of intraparticle diffusivity was then proposed to account for the impact of the APD of Z-HILIC Particles on the solid-to-liquid mass transfer resistance of small molecules. The model highlights the relevance of the thickness of the water diffuse layer, the access of the bulk eluent into the mesopore, the localized electrostatic adsorption, and the partitioning constant of the retained analyte between the bulk eluent and the water diffuse layer.

Silica 3D printed scaffolds as pH stimuli-responsive drug release platform

Silica-based scaffolds are promising in Tissue Engineering by enabling personalized scaffolds, boosting exceptional bioactivity and osteogenic characteristics. Moreover, silica materials are highly tunable, allowing for controlled drug release to enhance tissue regeneration. In this study, we developed a 3D printable silica material with controlled mesoporosity, achieved through the sol-gel reaction of tetraethyl orthosilicate (TEOS) at mild temperatures with the addition of different calcium concentrations. The resultant silica inks exhibited high printability and shape fidelity, while maintaining bioactivity and biocompatibility. Notably, the increased mesopore size enhanced the incorporation and release of large molecules, using cytochrome C as a drug model. Due to the varying surface charge of silica depending on the pH, a pH-dependent control release was obtained between pH 2.5 and 7.5, with maximum release in acidic conditions. Therefore, silica with controlled mesoporosity could be 3D printed, acting as a pH stimuli responsive platform with therapeutic potential.

Experimental study on selected properties and microstructure of pine-based wood ceramics

Abstract Wood ceramics using biomass materials as templates possess the benefits of facile fabrication and versatile applicability. To investigate the physical properties, chemical properties and microstructure of wood ceramics prepared from biomass materials, the basic properties and potential applications of wood ceramics were expounded. In this paper, wood powder wood ceramics (WPWC) and wood fiber wood ceramics (WFWC) were prepared through the vacuum carbonization method, utilizing pine powder and pine fiber as raw materials. The impact of phenolic resin concentration and mixture filling mass on various properties of wood ceramics, including mass loss rate (MLR), volume shrinkage rate (VSR), apparent porosity (AP), and bending strength (BS) were investigated on this basis. The microtopography and pore structure of wood ceramics were also analyzed. The test results show that an increase in the concentration of phenolic resin led to a decrease in the MLR, VSR, and AP of WPWC and WFWC, while their BS exhibited an increase. When the concentration of phenolic resin was 60 %, the phenolic resin yielded a BS of 8.70 MPa and 9.20 MPa for WPWC and WFWC, respectively. Furthermore, the microstructures of both WPFC and WFWC reveal hierarchical porous structures. The difference is that WPFC has a dispersed three-dimensional network topology in its overall morphology, which is mainly formed by filamentous or long linear glass carbon in wood ceramics dominated by carbon. The natural and consistent pore structure of WFWC is comparable to a three-dimensional honeycomb structure, the primary mesoporous size was around 40.28 nm and the main macropore size was more than 10,000 nm. It elucidates the pore structure of WPWC and WFWC, characterized by “hierarchical porosity”, the differences and relationships between porous wood ceramics derived from powdery and fibrous biomass as raw materials were analyzed, which contributes to the advancement of the fundamental principles of wood ceramics and establishes a theoretical basis for the practical exploration and development of biomass materials.

Sulfoaluminate cement-modified loess as bioretention cell filler for nutrient removal from stormwater runoff

In order to reduce the consumption of sand and gravel resources, the use of loess can reduce transportation costs and realize the in-situ construction of spongy in areas with rich loess resources. But the collapsibility and low permeability of loess make it unable to be directly used as the filler of bioretention cells. In this study, sulfoaluminate cement (SAC) mixed with a small amount of basalt fiber was considered to be used for loess modification, and the physicochemical properties and nutrient removal effect of SAC-modified loess as filler in bioretention cells were comprehensively evaluated. The results showed that when the SAC dosage was 15% and the basalt fiber addition was 0% (S15B0) and 0.6% (S15B6) and the curing time was 14 days, the stability and appropriate permeability can be exhibited, which can preliminarily satisfy the requirements of bioretention cell. SAC made the maximum adsorption capacity of S15B0 and S15B6 for ammonia nitrogen (NH4+-N) and phosphate higher than that of sand by 10.96%–31.51% and 45.92%–76.72%, respectively. The hydration products in SAC modified loess can fill the internal pores of loess particles and provide structural support, and ultimately reduce the accumulated pores, mesoporous pore size (20%) and surface homogeneity. Both S15B0 and S15B6 showed good removal effects of NH4+-N and COD. The TP removal efficiency was stable at 95.43%∼99.95%. Both the antecedent drying days and the submerged zone have an effect on the nitrogen removal in the bioretention cells, where a longer antecedent drying days is detrimental to the nitrogen removal, and the installation of a submerged zone improves the nitrogen removal. The basalt fiber can enhance the transformation process from nitrate-nitrogen to nitrite-nitrogen in the bioretention cell. Therefore, the modification of SAC can provide a certain idea for the in-situ use of loess as the filler of the bioretention cell.

Estimation of catalytic cracking of vacuum gas oil by ZSM-5- and β-zeolite-containing two-layered and novel three-layered hierarchical catalysts using Curie point pyrolyzer

ZSM-5- and β-zeolite-containing two-layered hierarchical catalysts (2 L-Z and 2 L-β) were prepared using a template of malic acid and novel three-layered hierarchical catalysts were also prepared combining mesoporous silica derived from the gel skeletal reinforcement (GSR) method with hexamethyldisiloxane (HMDS) - acetic anhydride (AA) as reinforcing agents. 2 L-Z and 2 L-β catalysts contained mesoporous silica of 50 wt% and microporous zeolite of 50 wt% and were called 2 L-Z-(Z50) and 2 l-β-(Z50) in which the amount of zeolite is shown in parenthesis. 3 L-co-gel and 3 L-mix, two types of three-layered hierarchical catalysts, were prepared by making GSR-silica in the presence of a 2 L catalyst for the former and by combining GSR-silica-gel with 2 L catalyst for the latter. 3 L catalysts contained 50 wt% of the 2 L catalyst and 50 wt% large-mesoporous GSR-silica and revealed three layered properties of microporous zeolite, small mesoporous silica and large mesoporous silica. Signals of zeolite crystals and amorphous phase were observed in XRD measurement for 3 L catalysts. Both smaller size of mesopores and larger size of mesopores were observed in N2 adsorption-desorption measurement. Vacuum gas oil (VGO) was catalytically cracked using 2 L and 3 L hierarchical catalysts with the use of Curie point pyrolyzer (CPP) method. ZSM-5-containing 3 L catalysts exhibited the lower conversions than corresponding 2 L catalyst, kaolin-mixed catalyst and ZSM-5 single while 3 L-co-gel-β-(Z25), which included 25 wt% of β-zeolite, exhibited the highest activity among β-zeolite-containing catalysts. The higher selectivity for p-xylene in xylene mixture was detected in catalytic cracking using 3 L-co-gel-Z-(Z25) and 3 L-mix-Z-(Z25) catalysts. When the relative activity against XRD integral intensity and amounts of acid sites was plotted against average pore diameter derived from N2 adsorption-desorption measurement, the strong correlation was observed, suggesting that the intrinsic activity of active sites of zeolite could be related to the pore size of the whole catalyst.

Combined Effect of Oxygen Vacancies and Mesopore Sizes in ZnO/SiO2 Adsorbents on Boosting the H2S Removal Efficiency in Moist Conditions

Combined Effect of Oxygen Vacancies and Mesopore Sizes in ZnO/SiO₂ Adsorbents on Boosting the H₂S Removal Efficiency in Moist Conditions

Flexible Mesopores in Nanoscrolls: Extraordinarily Large Alteration of Pore Sizes and Their Reversibility.

Flexible porous materials have gained considerable interest for their potential applications in selective absorption and controlled release/storage of specific molecules or compounds. Here, nanoscrolls are proposed as a type of inorganic solids with reversibly flexible mesopores. Nanoscrolls exhibit a rolled-up structure composed of nanosheets with a 1D rod-like morphology, possessing two distinct nanospaces. The first space comprises 1D tubular mesopores located at the center of the rod, while the second space exists in the interlayer regions on the wall of the mesopore, resulting from the layer stacking caused by the scrolling of nanosheets. By replacing the interlayer cations on the nanoscroll walls with other cations, a drastic alteration in the size of the 1D mesopores is observed. For instance, exchanging bulky dodecylammonium cations with small NH4 + cations leads to a substantial change in pore size, with differences ranging from 10 to 20nm-a notably larger variation compared to previous reports on flexible porous materials. Importantly, the alteration of pore size induced by the exchange reaction is found to be reversible. This reversible alteration in pore size holds promise for applications in host-guest chemistry involving large moieties such as nanoparticles and enzymes.

Tailored Hollow Mesoporous Carbon Nanospheres from Soft Emulsions Enhance Kinetics in Sodium Batteries.

Mesoporous materials endowed with a hollow structure offer ample opportunities due to their integrated functionalities; however, current approaches mainly rely on the recruitment of solid rigid templates, and feasible strategies with better simplicity and tunability remain infertile. Here, we report a novel emulsion-driven coassembly method for constructing a highly tailored hollow architecture in mesoporous carbon, which can be completely processed on oil-water liquid interfaces instead of a solid rigid template. Such a facile and flexible methodology relies on the subtle employment of a 1,3,5-trimethylbenzene (TMB) additive, which acts as both an emulsion template and a swelling agent, leading to a compatible integration of oil droplets and composite micelles. The solution-based assembly process also shows high controllability, endowing the hollow carbon mesostructure with a uniform morphology of hundreds of nanometers and tunable cavities from 0 to 130 nm in diameter and porosities (mesopore sizes 2.5-7.7 nm; surface area 179-355 m2 g-1). Because of the unique features in permeability, diffusion, and surface access, the hollow mesoporous carbon nanospheres exhibit excellent high rate and cycling performances for sodium-ion storage. Our study reveals a cooperative assembly on the liquid interface, which could provide an alternative toolbox for constructing delicate mesostructures and complex hierarchies toward advanced technologies.

A novel mesoporous carbon pocket with single atom Cr sites for high performance Lithium-Sulfur battery

Lithium-sulfur batteries (LSBs) are considered one of the most promising next-generation energy storage devices. However, their practical application is limited by the sluggish conversion kinetics and shuttle behavior of lithium polysulfides (LiPSs). In this work, we employ a facile salt template and micelle-mediated co-assembly strategy to synthesize atomic Cr dispersed mesoporous N-doped carbon pocket (denoted as Cr-mNC pocket). The designed Cr-mNC pocket exhibits uniform and ordered mesoporous caged morphology with a high surface area (843.5 m2/g), large pore volume (0.184 cm3 g−1), and uniform mesopore size (3.7 nm). The mesoporous structure offers a facilitated pump to promote electron/ion transportation while exposing more catalytic sites. These advantages enable the Cr-mNC pocket modified membrane to facilitate Li+ diffusion, enhance LiPSs adsorption, and accelerate electrochemical reaction kinetics for polysulfide conversion. Consequently, LSBs with Cr-mNC modified separator show a high sulfur utilization (1405 mAh g−1 at 0.2 C), a remarkable rate performance (776 mAh g−1 at 5 C), a low capacity decay rate of 0.047 % per cycle at 2 C over 1000 cycles, and even remain at 4.47 mAh cm−2 after 100 cycles with a high sulfur load of 5.0 mg cm−2.

Efficient adsorption of cationic and anionic dyes using hydrochar nanoparticles prepared from orange peel

Hydrochar nanoparticles biosorbent (HCNPs), derived from orange peel was prepared via an in-situ hydrothermal carbonization method. The HCNPs were tested as an effective biosorbent for removing cationic MB (methylene blue) and anionic MO (methyl orange) dyes. The prepared HCNPs was characterized using FTIR, CHN/O, SEM-EDX, UV–visible, XRD, PZC-titration, BET, and XPS. The biosorbent exhibits a good specific surface-to-volume ratio (28.23 m2/g and 0.069 cc/g, respectively) and mesopores size (2.41 nm). UV–Vis data confirm the graphitic nature of the carbon structures. XPS analysis reveals a high enrichment of multiple oxygen functionalities (including C-OH, C = O, and –COO- groups) on the surface. The optimal initial pHs are 3.0 and 5.0–8.0 for removing MO and MB, respectively. Electrostatic attraction plays a substantial role, with other hydrophobic forces in dye removal and binding. Equilibrium is attained during 60/90 min, with half-biosorption-time (tHST) for MB and MO are 4.72 and 6.71 min, respectively. The highest biosorption capacities are 203.4 mg/g for MB and 113.3 mg/g for MO, closely correlated with physiochemical characteristics. Experimental data follows Langmuir isotherm and PSO kinetic models, indicating monolayer chemisorption on a homogeneous surface. The biosorption process for both dyes is exothermic and spontaneous. HCNPs show high durability over multiple biosorption/desorption cycles using HCl and NaOH (0.1 M) for MB and MO, respectively. These findings highlight the promising potential of HCNPs as efficient biosorbents for removing both anionic and cationic dyes.