Types Of Functional Groups Research Articles

Tunable synthesis of heteroleptic zirconium-based porous coordination cages.

Zirconium-based porous coordination cages have been widely studied and have shown to be potentially useful for many applications as a result of their tunability and stability, likely as a result of their status as a molecular equivalent to the small 8 Å tetrahedral pores of UiO-66 (Zr6(μ3-O)4(μ2-OH)4(C8O4H4)6). Functional groups attached to these molecular materials endow them with a range of tunable properties. While so-called multivariate MOFs containing multiple types of functional groups on different bridging ligands within a structure are common, incorporating multiple functional moieties in permanently microporous molecular materials has proved challenging. By applying a mixed-ligand, or heteroleptic, synthesis strategy to cage formation, we have designed a straight-forward, one-pot synthesis of 10 Å zirconium-based molecular cages in a basket-shaped, or Zr12L6, geometry containing 3 : 3 ratios of combinations of two types of functional moieties from 11 different ligand options. Additionally, using more sterically hindered ligands, such as 5-benzyloxybenzene dicarboxylate, we show that ligand size governs the resulting cage geometry. This method allows for multiple functional groups to be incorporated in molecular cages and the ratio of moieties incorporated can be easily controlled. With this strategy in hand, we show that ligands for which zirconium cage syntheses have been elusive, such as 2,5-dihydroxybenzene dicarboxylate, have now been successfully incorporated into porous structures.

2B-OLEFIN Film Development

As Pelsan Tekstil, in order to bring sustainable solutions to the use of polymers in the world, we have developed the world's first biodegradation technology that can provide full microbial conversion of polyolefins in open environment. This technology can provide full biodegradation on PP & PE materials. The advanced catalytic system converts PP and PE materials into wax. Unlike oxo-degradation, no microplastics or toxic substances are left behind in the post- degradation stage, thanks to a bio-available wax that naturally occurring microorganisms can easily assimilate. According to research, polymer use in the world is over 311 million tons. While the demand for polymers is projected to increase by 5.1% between 2020 and 2030, the recycling rate is only 14%. The non-recyclable portion accumulates as waste in soil and oceans. Biodegradable polymers are biodegraded by various microorganisms and enzymes in nature and broken down into their natural components. Thus, they can be recycled into the natural cycle without leaving microplastics. However, they are considerably more expensive than non- biodegradable polymers. In addition, biodegradable polymers are very vulnerable to heat and are damaged during extrusion. Therefore, our project goal is to make our product biodegradable by using an optimum amount of additives with our standard polyethylene film production formulation without making any changes in the technologies we already use. The biodegradation process is dominated by different factors including polymer properties, the type of organism and the nature of the pretreatment. Polymer properties such as the mobility of the polymer chains, crystallinity, molecular weight, the type of functional groups and substituents present in the structure, the plasticizers or additives present, all play an important role during degradation. The additive has the ability to promote different chemical reactions upon the polymer structure simultaneously. Our individually formulated additive acts as an initial food-source for microbes to help boost the biodegradation in the early stages of decay. The technology is fully compatible with normal mechanical recycling processes. No adverse impact on the mechanical characteristics and optical aspect of recycled products when mixed into the standard recycled supply chain.

Synthesis of Cellulose Straw and Rice Husk as Raw Materials for Bioplastic Production

The development of environmentally friendly materials such as bioplastics is a solution to reduce the negative impact of conventional plastics on the environment. This study presents a novel approach by utilizing hemicellulose extracted from rice straw and husks—abundant agricultural waste materials—as the main raw materials for bioplastic production. Hemicellulose was extracted using the alkalization method, and its characterization was carried out through FTIR analysis to identify typical polysaccharide functional groups. The results of the analysis showed the presence of O-H, C-H, and C-O-C groups, which indicate the glycosidic structure of hemicellulose, as well as indications of residual lignin with C=C groups. The resulting hemicellulose was then processed into bioplastics with the addition of plasticizers and reinforcing materials, incorporating glycerin, CMC, and TiO₂ to enhance mechanical properties and biodegradability. Mechanical and degradation tests demonstrated superior performance, highlighting the synergy between these additives. This study provides an innovative strategy for transforming agricultural waste into high-value bioplastics, contributing to sustainability and advancing green material technology.

In English

Currently, there is increased interest in growing hemp as well as in large-scale hemp products. The main research focuses on the use of seeds and fibres. At the same time, the remaining hurd is proposed to be used for mulching, making insulation and bedding for animals. Due to the cellulose’s high content in its composition with a relatively low content of inorganic components, it can be a promising raw material for obtaining microcrystalline cellulose (MCC). Therefore, our work aimed to obtain MCC from hemp husks, establish its physicochemical characteristics and compare them with the indicators of MCC previously obtained from another flax culture. Air-dry hemp hurd, waste after the fibre extraction from technical hemp, was used for the research. It has the following characteristics: humidity of 8 %, the proportion of organic components to dry weight of 97.3 % (cellulose – 48.4, hemicellulose – 25.8, lignin – 20.9 % mass) and inorganic components – 2.7 %. To obtain microcrystalline cellulose, the hemp hurd was subjected to organo-solvent cooking. The structure and morphology of the MCC were studied using methods such as XRD, XRF, FTIR-ATR, low-temperature nitrogen sorption-desorption, AFM, TGA, and DSC. It was found that by the organo-solvent cooking method, it is possible to obtain MCC with a yield of 83.2 %. The resulting product was a white, tasteless, and odourless substance with 96.9 % organic components (including 98.5 % cellulose and 1.5 % lignin) and 3.1 % inorganic components (including 91.4 % SiO2). The XRD method confirmed the presence of a crystalline component in the obtained MCC due to the availability of the intensity of the peak reflex in the region 2θ = 22–23° which corresponds to the plane 002 of the crystal lattice of natural cellulose I. Based on these data, the crystallinity index was calculated – 0.88. The FTIR spectrum of the sample shows typical functional groups corresponding to MCC. There are two distinct mass loss steps in thermograms (TGA). It was found that the obtained samples had a specific surface area of 2.6 m2/g and a pore diameter of 3.6 nm, which indicates an MCC's non-porous structure. The AFM method shows that the particles are distributed throughout the scan, while there are no clusters of particles and their agglomerates, the height of which elements varies from 5.0 to 11.1 nm. Surface roughness Ra = 1.3–1.4 nm.

Characterization of Rice Husk for Graphene Extraction and Metallization

Rice husk, an underutilized agricultural waste product, serves as a potential precursor for graphene synthesis. This study focuses on synthesizing and characterizing graphene through the chemical exfoliation method, employing advanced analytical techniques to explore its potential applications in metallization. Graphene was produced by chemically activating rice husk ash (RHA) with potassium hydroxide (KOH) at 800 ºC. The extracted graphene underwent analysis using various techniques. X-ray Diffraction (XRD) confirmed the material's crystalline nature and graphitic structure. Fourier-Transform Infrared Spectroscopy (FTIR) identified typical functional groups present in the synthesized graphene. Raman Spectroscopy revealed significant defects and confirmed that the graphene consists of single or few-layer thin sheets. Transmission Electron Microscopy (TEM) showed the presence of thin graphene sheets and nanoparticles with sizes ranging from 1.47 nm to 5.80 nm. Ultraviolet-Visible Spectroscopy (UV-Vis) confirmed electronic structure and optical properties, essential for metallization. X-ray Fluorescence (XRF) confirmed the purity of the graphene, while Brunauer-Emmett-Teller (BET) analysis revealed a high specific surface area, making the material suitable for surface-based applications. Electrical conductivity tests demonstrated good conductivity in the lower to moderate current range. The study underscores the potential of rice husk-derived graphene for metallization, offering a cost-effective and eco-friendly synthesis method for industrial and commercial applications.

Characterization of Liquid Smoke and Charcoal from Cocoa Pod Husks (Theobroma cacao L.) in North Kolaka Regency

This study aims to characterize the pyrolysis products of cocoa pod waste from North Kolaka Regency, Southeast Sulawesi Province. Pyrolysis takes place at various temperatures between 112 - 512 oC and produces liquid smoke and charcoal products. The highest liquid smoke yield was obtained at a temperature of 212 oC of 20.05%. The results of GC-MS analysis showed that liquid smoke contains many potential compounds consisting of acetic acid compounds with the highest concentration of 28.1%, Phenol, 2-methoxy- (CAS) Guaiacol with the highest concentration of 4.18%, 3-Hexine-2,5-diol (CAS) Hexine-3-diol-2,5 of 2.94%, and several aromatic and alcohol compound groups. FTIR analysis shows that the typical functional groups of cocoa pod charcoal consist of OH (hydroxyl) and C = C-H (aromatic) groups. XRD analysis shows that charcoal is dominated by an amorphous phase with a degree of crystallinity of 14%. Liquid smoke and cocoa pod charcoal have the potential to be used as raw materials in the chemical, health and manufacturing industries.

Effect of Additives With Phenyl and Acid Anhydride Functional Groups on the Wide Temperature Operation Performance of LiNi0.8Co0.1Mn0.1O2||SiO/Graphite Pouch Cells

ABSTRACTHigh‐nickel LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode paired with silicon‐based graphite (SiO/Gr) is pivotal for enhancing the energy density of lithium‐ion batteries (LIBs). However, the high reactivity of NCM811 with the electrolyte and the volumetric expansion issues associated with SiO/Gr pose significant challenges to their practical application. To settle these issues, we explore the impact of additives with phenyl and acid anhydride moieties on the performance of NCM811‖SiO/Gr pouch cells across a wide temperature range of −20°C~60°C. Acid anhydride additives are capable of diminishing the internal resistance in NCM811‖SiO/Gr pouch cells, as well as curbing gas evolution and thickness increase during the operational phase. Notably, the batteries enriched with citraconic anhydride (CAn) and succinic anhydride (SAn) additives after 120 cycles at 45°C demonstrated enhanced capacity retention from 83.2% to 88.1% and 85.5%, respectively. Intriguingly, the inclusion of phenyl‐containing additives in the electrolyte was found to be advantageous for NCM811‖SiO/Gr pouch cells' low‐temperature performance. Furthermore, neither type of functional group significantly enhanced performance at room conditions. Consequently, the combination of additives is necessary to fulfill the stringent requirements of LIBs for extreme environment applications. This work guides designing composite electrolytes for high energy density wide temperature operation LIBs.

Triftosylhydrazone in Single-Atom Skeletal Editing.

ConspectusIn the past decade, single-atom skeletal editing, which involves the precise insertion, deletion, or exchange of single atoms in the core skeleton of a molecule, has emerged as a promising synthetic strategy for the rapid construction or diversification of complex molecules without laborious de novo synthetic processes. Among them, carbene-initiated skeletal editing is particularly appealing due to the ready availability and diverse reactivities of carbene species. The initial endeavors to modify the core skeleton of heteroarenes through carbon-atom insertion could date back to 1881, when Ciamician and Denstedt described the conversion of pyrroles to pyridines by trapping haloform-derived free carbene. Despite its potential synthetic value, the general applicability of this one-carbon insertion has seen limited progress due to poor yields and harsh reaction conditions. Significant advances in skeletal editing via carbene insertion were achieved only in the past 3 years by Levin, Ball, Xu, Song, Glorius, and others. The hallmark of these approaches is facile halocyclopropanation followed by regioselective ring opening facilitated by the expulsion of the halide ion. Consequently, only specially designed α-halocarbene precursors, such as haloform derivatives, α-halodiazoacetates, chlorodiazirines, and α-chlorodiazo oxime esters, can be employed to achieve Ciamician-Denstedt-type skeletal editing. This not only limits the types of functional groups installed on the ring expansion products but also prevents their widespread adoption, especially in late-stage contexts. The enduring quest to develop environmentally friendly and versatile carbene precursors, superior functional group compatibility, and potential application in late-stage diversifications and the investigation of mechanistic insights into carbon insertion reactions remain a fundamental objective.In our endeavors over the past 5 years, we have developed o-trifluoromethylbenzenesulfonylhydrazones (named Triftosylhydrazones) as operationally safe and easily decomposable diazo surrogates and explored their application in various challenging catalytic carbene transfer reactions. Recently, our group has put great efforts into expanding the application scope and unlocking the potential of triftosylhydrazones as carbene precursors in single-atom skeletal editing reactions. Since 2018, we have realized a range of skeletal editing of acyclic 1,3-dicarbonyls with silver carbenes to access 1,4-dicarbonyls, proceeding through a cyclopropanation/ring-opening process. Inspired by these results, we recently demonstrated a series of transition-metal-catalyzed highly selective single-atom skeletal editing of medicinally interesting heteroarenes like pyrroles, indoles, and 1,2-diazoles via carbenic carbon insertion. We then achieved the skeletal editing of strained three-membered nitrogen- and oxygen-containing heterocycles through the insertion or exchange of single-carbon atoms. In this Account, we present an overview of our achievements in the single-atom skeletal editing of heterocycles, organized based on three types of in situ-generated key intermediates, such as cyclopropane, N-ylide, and O-ylide from triftosylhydrazones and heterocycles, with a focus on reaction scopes, mechanistic features, and synthetic applications. We hope that this Account will provide valuable insights and contribute to the development of new methodologies in both the skeletal editing and carbene chemistry fields.

SYNTHESIS AND CHARACTERIZATION OF SILICA GEL/CHITOSAN COMPOSITE DERIVED FROM TIN TAILING FOR REMOVAL OF Fe(III) IN POST-TIN MINING WATER

A study on the synthesis and characterization of silica gel/chitosan composite derived from tin tailings for removal of Fe(III) in post-tin mining water has been carried out. The silica source used for the synthesis of silica gel is tin tailings. It is produced by the sol-gel method. The characteristics of silica gel from tin tailings sand are white powder with a silica content of 73.58% after compositing with 30 mL and 45 mL chitosan solution, showing that the chitosan phase was successfully formed together with the silica phase. Functional group analysis showed the presence of typical chitosan functional groups (-NH2) at 1629 cm-1 and 1635 cm-1 and typical silica functional groups (-Si-O-Si) at 1000 cm-1 to 1020 cm-1. These functional groups appeared in addition to all variations of the chitosan solution. Morphological analysis shows that in the addition of 45 mL chitosan solution, the silica gel/chitosan composite has a morphology in the form of small round particles with uneven surfaces and more dominant pores. Adsorption study of silica gel/chitosan composite on Fe(III) in post-tin mining water showed 95.5% adsorption efficiency in the addition of 45 mL chitosan solution. The adsorption condition observed is the adsorption time as a fixed variable in this study, which is for 17 hours.

Design of a LiF-rich solid electrolyte interphase layer through a fluorinated carbon (CFX) complex separator for stable lithium metal batteries

The formation of a stable solid electrolyte interphase (SEI) layer is very important for improving the cycling stability and safety of lithium metal batteries (LMBs). However, since the reactivity of lithium metal anodes (LMAs) is very high, controlling the movement of Li+ at the anode/electrolyte interface remains challenging. In this study, an approach involving coating a fluorine functional-controlled fluorinated carbon (CFX) layer onto a commercial PE separator to form a stable SEI layer was proposed. The strong reaction between the fluorine functional groups constituting CFX and Li+ facilitated the rapid formation of a LiF-rich SEI layer in the resting and initial cycling stages. This initial stable SEI layer promoted a subsequent homogeneous Li+ flux, thus improving the LMA stability. In addition, the mechanism by which the total amount of fluorine and the fluorine functional groups control the Li+ dynamics through the CFX-coated PE separator with controlled fluorine functional groups was used to identify the mechanism by which the total amount of fluorine and the fluorine functional groups provide the advantage of the creation of a stable SEI layer. Therefore, this study contributes to the energy storage field by solving the cycling stability problem related to LMAs and emphasizes that a stable SEI layer can be formed based on the important interface control according to the type of fluorine functional group.

Optimization of Nano-Hydroxyapatite Production from Limestone with Effect of Gelatin Concentration and pH in Sol-Gel Synthesis

Nano hydroxyapatite is one of the biomaterials that has proven to be a very potential material due to its ability to bind directly with bone tissue. Limestone with a calcium carbonate content of 99.87% was used as a calcium source for the economical and sustainable synthesis of hydroxyapatite. The sol-gel method was chosen for the in situ gelatin synthesis process due to its ability to produce nanoparticles with high homogeneity. The particle size of nanohydroxyapatite can increase the surface area to volume ratio thus affecting the interaction with surrounding cells and tissues. Gelatin was added in various concentrations of 10%, 20%, and 30% as an innovative cell growth support modifier. The synthesis was also carried out at pH 9, 10, and 11 to evaluate its effect on hydroxyapatite formation. Optimal synthesis conditions were obtained at 30% gelatin concentration and pH 10, which resulted in the highest yield of 93.95%. Product characterization included Fourier Transform Infra-Red analysis, which showed the presence of typical hydroxyapatite functional groups (PO₄³-, OH-) and carbonate groups (CO₃²-). Scanning Electron Microscopy characterization showed nano-sized particles in the range of 443-578 nm with a granular structure. Porosity was found to be 72.52% making it ideal for cancellous bone tissue engineering applications.

Structural Characterization and Hypoglycemic Activity of a Glycoprotein Extracted from Auricularia Auricula.

Glycoproteins are special proteins and important nutrients for hypoglycemic activity. However, the structure of Auricularia Auricula glycoprotein (AAG) and the stability of its hypoglycemic activity during simulated digestion (including saliva, gastral and intestine digestion) in vitro are still unknown. In this study, AAG-3 was isolated from Auricularia Auricula. SDS-PAGE, UV spectrum, FTIR, amino acid composition, dichroic spectrum and SEM were used to characterize its structure. The hypoglycemic activity of AAG-3 during in vitro digestion was investigated via inhibition of α-amylase and α-glucosidase activities, as well as glucose consumption, glycogen content and related enzyme activity in insulin-resistant HepG2 cells. Structural characterization showed that AAG-3 with a Mw of 18.21 kDa had an O-type glycopeptide bond and typical functional groups of glycoproteins. AAG-3 contained 18 kinds of amino acid and many α-helixes and β-turns, and its microstructure was sheet-like. With the simulated digestion of AAG-3 in vitro, the inhibition of α-amylase and α-glucosidase activity as well as the glucose consumption, glycogen content and HK and PK enzyme activities in insulin-resistant HepG2 cells were significantly increased. Therefore, AAG-3 has a potential role in reducing blood glucose levels and improving insulin resistance and can be used as a potential micronutritional supplement for diabetic patients.

Efficient membrane separation of SO2 by choline chloride-based natural deep eutectic solvents: the role of hydrogen bonding sites

Natural deep eutectic solvents (NDESs) are recognized as promising membrane materials for sustainable SO2 separation. Evaluating their separation performances is necessary, as well as understanding of the role that each hydrogen bonding site (including anion and functional groups in NDESs) plays in SO2 separation. Herein, three choline chloride (ChCl)-based NDESs bearing different number and type of functional groups were firstly incorporated into Pebax matrix to fabricate blended membranes for removing SO2 from CO2 and N2. The Pebax/NDES membranes show SO2 permeability up to 10502 Barrer (0.20 bar and 40 °C), with excellent SO2/N2 and SO2/CO2 selectivity of 1808 and 62.5 obtained, respectively, which are enhanced by 156 %, 61.5 % and 56.1 % compared with those in neat Pebax membrane. By means of gas solubility and diffusivity measurements, quantum chemical calculations and spectral characterizations, the highly-reversible multi-site interactions between SO2 and hydrogen bonding sites in NDESs (Cl−···SO2, carbonyl O···SO2 and hydroxyl O···SO2) were revealed. Meanwhile, the strength of hydrogen bonding network inside the NDESs, which is governed by the hydrogen bonding sites, is found to significantly influence the gas diffusion. More importantly, SO2/CO2/N2 (2.5/15/82.5 mol%) mixed gas separation experiment also displays the superior separation performance and long-term stability of Pebax/NDES membrane.

Study of Surface Repair Materials for Aged Silicone Rubber Insulators

The aging phenomenon of silicone rubber insulators can bring great safety risks for the stable operation of high-voltage transmission lines. To avoid the significant costs and prolonged downtime associated with completely replacing insulating equipment, our research described in this paper proposes a surface repair material for aged silicone rubber insulators using α, ω-dihydroxy-polydimethylsiloxane as the matrix. The material was, after preparation, uniformly applied to the surface of insulators that had been in grid operation for more than 14 years. The chemical structure, elemental composition and surface morphology of the insulator surfaces were characterized both before and after repair. Our research described here also examined the changes in mechanical properties, insulating resistivity, water repellency and adhesion strength of the insulators. The data showed that the functional group types and element contents on the surface of the repaired silicone rubber insulators were restored to those of the new insulators, and the surface and internal cracks were also effectively repaired. Moreover, the water-repellent, mechanical, and electrical properties underwent a notable enhancement. The robust adhesion between the repair material and the deteriorated surface resulted in the formation of a stable and robust adhesive interface. The results demonstrated that the materials created for the purpose of repair in our research had the capability to efficiently enhance the performance of aged insulators. Furthermore, we suggest this study presented a novel path toward addressing the predicament of aging insulation equipment.

Supercapacitive behavior of two-dimensional carbon nanosheets with oxygen-induced interfacial modification

Biomass-derived carbon typically contains abundant heteroatomic defects and interfacial functional groups, which can contribute to additional pseudocapacitance. However, the type of interfacial functional groups in biomass-derived carbon is uncontrollable and variable, reducing their homogeneity. In this work, recyclable boric acid was employed as an activator to convert bioaerogels into carbon nanosheets. Subsequently, low-temperature air oxidation was utilized to modulate their thickness and microstructure. Notably, the multiple and uncontrollable functional groups at the carbon interface were uniformly transformed into oxygen-containing functional groups under oxygen induction, resulting in 2D carbon nanosheet materials with enhanced stability properties. Meanwhile, the introduction of more oxygen-containing functional groups, such as carbonyl (C=O) and carboxyl (-COOH) groups, improves material wettability and capacitive properties. In addition, the boron and nitrogen elements doping introduced by activators and precursors enhances its pseudocapacitive properties and electrical conductivity from the carbon lattice perspective. Moreover, the rich electron/deficient effect of BN valence bond can effectively boost their conductivity and rate performance. In fact, the materials present good capacitive properties (high specific capacitance of 298.5 F g−1 in KOH three-electrode system) and CDI (capacitive deionization) performance (good desalting capacity of 35.2 mg g−1 in CDI system).

Probing the formation mechanisms of reactive oxygen species in graphene oxide-catalyzed ozone advanced oxidation processes

Graphene oxide (GO), a representative carbon-based catalyst, has demonstrated promising prospects for oxidation removal of organic pollutants in ozone (O3)-based advanced oxidation processes (AOPs). However, due to complex reactions of realistic ozonation processes, the functional mechanisms of oxygen-containing functional groups of GOs remain ambiguous, which are generally difficult to identify by single experimental characterization. Herein, we applied density functional theory (DFT) to investigate the physical interactions and chemical reaction mechanisms between O3 and oxygen-containing functional groups of GO in aqueous media. It is demonstrated that the functional groups on GOs could promote the generation of various reactive oxygen species (ROS) through different ozonation mechanisms, which include direct activation and indirect H-abstraction. The connection between types of functional groups and the generated ROS has been established. Further reactive molecular dynamics simulations were used to dynamically capture the catalytic ozonation events for the functional groups of GOs. The simulated type changes of functional groups and time evolution of the ROS-related species number show consistent behavior with the above DFT computations. The proposed mechanisms provide an improved understanding of ozonation catalysis, which is expected to advance the development of AOP technologies utilizing GO catalysis.

New insights into the functional group influence on CO2 absorption heat and CO2 equilibrium solubility by piperazine derivatives

Piperazine (PZ) derivatives which have been widely used in CO2 capture technology exhibit stable physicochemical properties, such as resistance to thermal degradation and low regeneration energy consumption. Both two parameters of CO2 absorbents, low CO2 absorption heat (ΔHabs) and large CO2 equilibrium solubility (αe), are important to CO2 capture performance. However, the influence of functional group types of PZ derivatives on their CO2 capture performance remained unclear. This research aimed to study the functional group influence on the ΔHabs and αe by PZ derivatives with two amines using experimental and quantum chemical methods. The results indicated that PZ derivatives with the ethyl side chain had larger ΔHabs and αe than those with the methyl side chain. The presence of the hydroxy group in PZ derivatives reduced the ΔHabs and the αe. The presence of cyclic methyl side chains on the N atom of PZ derivatives decreased the ΔHabs and increased αe at the same time. The findings show that PZ derivatives with cyclic methyl side chains, steric hindrance effect, and no hydroxy group are favorable for CO2 capture. Among the eight PZ derivatives, TEDA with lower ΔHabs (48.99 kJ/mol) and higher αe (0.917 mol CO2/mol amine) is an excellent absorbent. The results of this study are very important for screening efficient and low-energy consumption absorbents for CO2 capture.

Lignin as a bioderived modular surfactant and intercalant for Ti3C2Tx MXene stabilization and tunable functions

Controlled tailoring of atomically thin MXene interlayer spacings by surfactant/intercalants (e.g., polymers, ligands, small molecules) is important to maximize their potential for application. However, challenges persist in achieving precise spacing tunability in a well-defined stacking, combining long-term stability and dispersibility in various solvents. Here, we discovered that lignin can be used as surfactants/intercalants of Ti3C2Tx MXenes. The resulting MXene@lignin complexes exhibit superior colloidal stability and oxidation resistance in both water and different organic solvents. More important, we reveal a dynamic interaction between MXene and lignin that enables a wide-range fine interlayer distance tuning at a sub-nanometer scale. Such dynamic interaction is sparse in the reported organic surfactants/intercalants containing single types of functional groups. We also demonstrate the tunability of electrical conductivity, infrared emissivity, and electromagnetic interference shielding effectiveness. Our approach offers a starting point to explore the potential of MXene-biomacromolecule composites for electronics and photonics applications.

Cnicus Benedictus roots as a low-cost adsorbent for methylene blue dye removal from aqueous solution: kinetic and equilibrium studies

In this research, Cnicus Benedictus roots powder (CBRP) was utilized as a low-cost adsorbent for removing methylene blue (MB) as a cationic dye from aqueous solution. Characterization of CBRP by Boehm titration method, Fourier transform infrared (FT-IR) and environmental scanning electron microscope (ESEM) indicates the presence of different types of functional groups and a very rough surface filled with cavities, suitable for MB adsorption. The effect of various parameters such as CBRP dose (0.2–2 g/1L), contact time (0–180 min), initial pH (1–10), coexisting anions/cations and the initial MB concentration (100–500 mg L−1) on MB adsorption were examined, the results showed that MB uptake depends on the pH of solution, the electrostatic attraction forces, the formation of H-bonds and π–π interactions are the possible CBRP–MB interaction mechanisms. Adsorption kinetic of MB on CBRP was best represented by linear and non-linear form of the pseudo-second order model. The experimental equilibrium data were best described by linear and non-linear forms of Langmuir and Redlich–Peterson isotherm models (R 2> 0.98) with a maximum MB adsorption capacity of 85.47 mg g−1 at 25 °C, the adsorption efficiency R (%) was greater than 90 (%). MB adsorption-desorption experiments showed the reusability of CBRP for five consecutive cycles. According to the obtained results, CBRP can be used as a natural adsorbent material for cationic dyes removal from aqueous solution.

Carbon fiber with superhydrophilic interface as metal-free air electrode for all-solid-state Zn-air batteries

The burgeoning interest in all-solid-state Zn-air batteries as next-generation power sources for portable electronics is conspicuous. A pivotal aspect of their advancement lies in developing cost-effective, metal-free air electrodes with high-activity bifunctional oxygen electrocatalysts. This study introduces a superhydrophilic carbon fiber modified with oxygen functional groups (CF-O), achieved through a straightforward one-step activation treatment. Comparative analyses reveal that the CF-O electrode surpasses pristine CF in oxygen reduction and evolution reaction (OER and ORR) activity due to enhanced active sites and expedited ion transport. Notably, the OER/ORR performance depends on the type and quantity of oxygen functional groups. The optimal CF-O electrode displays an OER overpotential of 365.6 mV at 10 mA cm-2 and an ORR peak potential of 0.683 V. Utilizing the CF-O sample as the air electrode in all-solid-state Zn-air batteries yields an open-circuit voltage of 1.28 V and a peak volume power density of 82.8 mW cm-3. Furthermore, endurance testing reveals a charge/discharge voltage gap of 1.07 V at a current density of 1.0 mA cm-2 after 30 cycles. This facile and economical fabrication approach for metal-free air electrodes holds promise for advancing high-performance metal-air batteries compared to various existing techniques.