BET Analysis Research Articles

Feasibility Study of Magnesium Slag, Fly Ash, and Metakaolin to Replace Part of Cement as Cementitious Materials

To achieve the efficient utilization of magnesium slag, this study investigates the use of magnesium slag, fly ash, and metakaolin as partial substitutes for cement in cementitious materials. The reactivity of these materials is assessed based on the compressive strength of mortar. The response surface methodology is employed to explore the influence of material proportions on the strength performance of cement mortar. The mechanisms underlying strength development in the composite system are examined through XRD, SEM, TG-DTG, and BET analyses. Additionally, the effect of magnesium slag on the drying shrinkage properties of cement mortar is studied. The experimental results indicate that magnesium slag exhibits low reactivity and cannot be used alone as an active admixture. The optimal proportion of magnesium slag, fly ash, metakaolin, and cement is 10:10:10:70, achieving over 80% of the strength of pure cement mortar and approximately 1.5 times the strength of cement mortar containing 30% magnesium slag. Furthermore, magnesium slag helps mitigate the volume shrinkage caused by drying in cement mortar. Therefore, this study can facilitate the comprehensive utilization of magnesium slag in the construction sector, reducing its negative impact on the ecological environment.

Investigation of the kinetics of imidacloprid adsorption onto bimetallic Cu-BTC MOF

Imidacloprid, which is harmful for humans as well as many other aquatic invertebrate species, is extensively present in water worldwide. Hydrophobic Cu-BTCIPA and a novel composite, Ag@Cu-BTCIPA, was synthesized for adsorption of imidacloprid from water. The synthesis of the composite and the increase in surface area and pore volume were confirmed by FTIR, XRD, SEM, and BET analysis. A comparative study of the adsorption efficiencies of the synthesized composites was performed. The maximum adsorption efficiency achieved was 83.6 % at pH 7 by the Ag@Cu-BTCIPA composite. Kinetic and isotherm analyses suggested multilayer chemisorption involving p-p conjugation and pore-filling mechanisms. Intra-particle diffusion was the rate limiting step. Release studies of imidacloprid from water showed that the percentage release amount was 90.2 % at 70 min. Kinetic analysis of the release process suggested release through chemisorption, with swelling-controlled release from the dosage form, corresponding to the super case II transport mechanism.

Manganese cobalt oxide-polythiophene composite for asymmetric supercapacitor

In this work, the synthesis of manganese cobalt oxide (MCO) and polythiophene (PTh) composite on Ni-foam is carried out using two step chemical methods. The MCO/PTh films are analyzed by various characterization techniques to study its structural, morphological and electrochemical aspects. The polycrystalline nature of MCO in MCO/PTh composite is confirmed from XRD analysis while presence of various functional groups in MCO/PTh is validated by FT-IR study. Oxidation state of manganese, cobalt and sulfur in the MCO/PTh composite are confirmed from EDAX and XPS analysis. The highest specific surface of the MCO/PTh sample is found about 63.3 m2/g from BET analysis. The deposition of fibrous polythiophene on the MCO nanoflakes is revealed by FE-SEM images while it is further validated by TEM analysis. The electrochemical characterizations of the MCO/PTh composite are carried out by different techniques. The specific capacitance of 1643.08F/g (6386.01 mF/cm2) at 20 mA/cm2 is showed by MCO/PTh electrode at optimized conditions. The electrochemical kinetics of the optimized sample is carried out to understand the charge storage dynamics for the MCO/PTh composite. The capacitance retention of 98 % is exhibited by MCO/PTh electrode after 5000 cycles. Additionally, the aqueous asymmetric supercapacitor, having 1.7 V potential window is tested. The device MCO/PTh//AC exhibited a specific capacitance of 133.47F/g with energy and power density of 53.5 Wh/kg, 13.3 kW/kg at 50 mA/cm2. The obtained results showed that utilization of this synergy of metal oxide with polymer composite can be a potential candidate for supercapacitors.

Green electrochemical sensor for selective determination of anticancer drug Ribociclib based on banana peel activated carbon/CuCoFe-MOF/CoFe2O4 modified carbon paste electrode in pharmaceutical and biological samples

The development of efficient and eco-friendly sensing platforms for the sensitive detection of anticancer drugs like Ribociclib (RIB) is essential for advancing therapeutic monitoring and ensuring patient safety. In this study, we introduce a novel electrochemical sensor that utilizes a unique CuCoFe-MOF/CoFe2O4/banana peel activated carbon (BPAC) composite-modified carbon paste electrode (CPE) for the sensitive quantification of RIB. This composite material, which has not been previously reported in the literature, offers enhanced electrocatalytic activity, attributed to its increased surface area and superior conductivity. Various techniques, including FT-IR, XRD, SEM-EDX, and BET analysis, were used to confirm the structural and morphological properties of the synthesized composite. Differential pulse voltammetry (DPV) results showed a broad linear range of 0.2–9.7 μM and a remarkably low limit of detection (LOD) of 0.025 μM, demonstrating its high sensitivity. The sensor’s performance was further validated in pharmaceutical formulations and biological samples, achieving recoveries between 98.6 % and 101.8 % with an RSD below 2.0 %. Additionally, the method was evaluated using the Green Analytical Procedure Index (GAPI), Analytical Greenness (AGREE), and Blue Applicability Grade Index (BAGI) tools, confirming that it is both green and highly applicable. This work presents a significant advancement in the field of electrochemical sensing for RIB detection, offering a novel, sustainable, and practical solution for real-world applications.

Cathodic catalyst from lemon peel-based hydrogel for application in a SCMFC

In this investigation, a hydrogel has been prepared with the filling of lemon peel powder (LP) at three different concentrations of 1, 1.5, and 2 g (CS-PF/LP1, CS-PF/LP1.5, and CS-PF/LP2), in a mixture of phenol formaldehyde resin and chitosan, and they are pyrolyzed at 700°C to get soluble metal and nitrogen-doped carbon as cathode catalysts for oxygen reduction reaction (ORR). Several analytical characterization results confirmed the presence of inherent metallic content (or soluble metal) in the LP power. Among the three, CS-PF/LP1 provides the maximum surface area of 259.38 m2g-1, which is confirmed by the BET analysis. Additionally, the highest conductivity and catalytic activity of CS-PF/LP1 are also confirmed by electrochemical analysis. Thus, CS-PF/LP1 was selected to be used in a single-chamber microbial fuel cell (SCMFC) as a cathode catalyst. A maximum power density of 170.67 mWm-2 is obtained for CS-PF/LP1 which is 5.70 times higher than the base catalyst (without LP). Therefore, the present work uses LP, a waste material to develop a porous carbon material that can be used as an efficient cathode catalyst using solely the soluble metals of LP, for ORR in SCMFC for efficient power generation.

Nanomolar level detection of phosphodiesterase 5 inhibitor drug tadalafil based on halide perovskite@HNTs nanocomposite electrode

As halide perovskites have taken a central role in the evolution of semiconductor materials, they are setting new standards for performance and revolutionizing the energy sectors. Unfortunately, little light is shed on the material's electrochemical sensing capabilities. This work reports the synthesis and characterization of a novel double halide perovskite Cs2CaSnCl6 (HDP) integrated with halloysite nanotubes (HNTs) for the electrochemical detection of Tadalafil (TAD). HDP@HNTs nanocomposite is synthesized using a simple solvothermal method and is characterized using various techniques like SEM, TEM, UV-visible, FT-IR, TGA/DTA, XRD and BET analysis. The results obtained from these characterizations confirmed the successful formation of the nanocomposite, revealed the material's endurance to high temperatures and the availability of a large surface area for reaction. Electrochemical characterization techniques like cyclic voltammetry (CV) and linear sweep voltammetry (LSV) demonstrated a linear correlation with the concentrations of TAD. Computational analysis of the TAD structure optimization, molecular electrostatic potential (MEP) of TAD and calculations regarding the HOMO-LUMO molecular orbitals are all carried out using the DFT/B3LYP method. The HDP@HNTs sensor is capable of achieving the lowest detection limit of 1.68 nM and the limit of quantification of 5.09 nM. The material showcased a remarkable sensitivity of 0.0104 µA nM-1 cm-2 from all the electrochemical parameters. Its reliability and stable performance even in the presence of real samples makes it a promising material for sensing applications. Thus, the reported framework contributes to the advancement in the development of sensors and enhanced healthcare outcomes.

UiO-66 MOF/Zr-di-terephthalate/cellulose hybrid composite synthesized via sol-gel approach for the efficient removal of methylene blue dye.

This research addresses the issue of organic dye pollution in water by developing eco-friendly, cost-effective adsorbents. Zr-di-terephthalate organic-inorganic hybrid materials, with and without cellulose, were synthesized using a one-pot sol-gel method with zirconium butoxide and terephthalic acid. The materials were characterized by XRD, FTIR, XPS, SEM, EDS, TEM, and BET analysis and showed a crystalline structure with some amorphous content, high surface area, and small pores, indicative of a composite form containing UiO-66 metal-organic frameworks (MOFs). Adsorption studies on methylene blue dye showed that both materials followed Langmuir isotherms, with maximum adsorption capacities of 147.54 mg/g for Zr-(TPA)2-U and 151.38 mg/g for Zr-(TPA)2-UC. The materials exhibited rapid adsorption within a short period of 30 min and adhered to pseudo-second order kinetics. The adsorption process was spontaneous and endothermic, driven by electrostatic interactions, π-π stacking, pore filling, van der Waals forces, and hydrogen bonding. The fact that the composite materials contain the UiO-66 structure contributed to their effective adsorption by increasing the crystalline properties of the material. The hybrids also showed excellent reusability, maintaining high efficiency over multiple cycles. These findings highlight the potential of Zr-di-terephthalate hybrids as sustainable, high-performance adsorbents for water purification, addressing dye contamination effectively.

Fabrication of chitosan coated bentonite clay multifunctional nanosorbents from waste biomass for the effective elimination of hazardous pollutants from waterbodies: A fixed bed biosorption, mechanism, and mathematical model study

The anthropogenic activity and hasty fluctuating technologies have been responsible for the generation of massive effluent which is so hazardous due to the loading of several toxicants. While most industries usually discharge it directly into the environment resulting in harsh damage to the ecology/public security. Therefore, it is critical to treat with a sustainable/cost-effective technique. Here, a new route of fabrication of chitosan-coated activated natural bentonite clay (CCANBC) bionanocomposites/bionanosorbents from waste biomass has been developed. Their potential application for the simultaneous removal of Ni2+ and Eosin Y from wastewater were investigated. The effective parameters like concentration (10–30 ppm), flow rate (2–4 mL/min), and bed height (0.5–1.5 cm) were inspected. The bionanosorbents were characterized by FTIR-ATR, XRD, FESEM, TGA, and BET analysis. Additionally, the effluents were explored by AAS and UV–vis-NIR spectroscopy. According to the findings it has been stated that the CCANBC bionanosorbents possessed significant dynamic edges, greater crystallinity (94.27 %), and higher thermal stability. They have exhibited a remarkable 2D honeycomb-like mesoporous microstructure with substantial specific surface area (19.29 m2/g). These outstanding features could be responsible for the dramatic adsorption enactment around 186.42 and 238.37 mg/g for Ni2+ and Eosin Y. The obtained data were evaluated by several mathematical models for better understanding the experimental BTC curve, reaction mechanism, and adsorption isotherm.

Blended mangosteen/pomegranate peels as a precursor for porous carbon material via microwave assisted‑potassium carbonate activation: Box-Benken design optimization for fuchsin basic and methylene violet dyes removal

Solid waste disposal and water pollution are the critical issues. Thus, this work aims to convert common domestic fruit wastes namely mangosteen peel (MP) and pomegranate peel (PP) into a mesoporous activated carbon (MPPP-AC) via microwave-induced strong alkaline salt (K2CO3) activation. The potential application of MPPP-AC was tested for the removal of two structurally different toxic cationic dyes namely fuchsin basic (FB) and methylene violet (MV). The physicochemical properties of MPPP-AC were analyzed utilizing several analyses such as XRD, SEM-EDX FTIR, pHpzc, and BET analysis. The adsorptive performance of MPPP-AC was optimized by using response surface methodology (RSM) with Box-Behnken design (BBD). Three key adsorption variables including the dose of MPPP-AC (A: 0.02–0.1 g/100 mL), solution pH (B: 4–10), and time of contact (C: 10–60 min) were optimized in the BBD. The highest FB removal and MV removal were found to be 80.2 % and 92.8 % respectively at 0.1 g/100 mL of MPPP-AC dosage and solution pH = 10. Thus, the best fit for the adsorption isotherm data for FB and MV dyes was the Freundlich model, whereas the pseudo-second-order model was best explained for the kinetic data. The MPPP-AC has maximum adsorption capacity for FB (85.5 mg/g) and MV (90.1 mg/g). Various forms of interaction were involved in the MV and FB dye binding process onto MPPP-AC such as the filling of pores, π-π stacking, hydrogen bonding, and electrostatic forces. The finding of this research exhibits the possibility of transforming a blending of MP and PP wastes into activated carbon which shows desirable adsorptive performance for eliminating cationic dyes from water.

Hybrid organic - inorganic filter system for cadmium ions adsorption from aqueous solutions

The study reflects on the problem of heavy metals, namely cadmium, polluting the natural environment. The goal was to select the most efficient adsorber enabling ion exchange between calcium and cadmium in an aqueous environment and subsequently design a material hybrid organic-inorganic, particle-fiber system that adsorbs cadmium from aqueous environments and will be easily included in the technological process. The novelty of this study lies in the use of waste food material – eggshells as a source of biogenic nanoparticles. These are applied to a nanofibrous structure made of polyvinyl butyral in amounts of 8 to 10 %wt by weight by the AC electrospinning. (The experiment was performed with these boundary conditions: temperature was 23°C, and humidity was 42%. The high-electrical voltage amplifier generated a sinusoidal waveform with a frequency of 50 Hz and an amplitude of 32 kV) and were used for ion exchange. In ion exchange, cadmium ions are exchanged with calcium ions based on the principle of chemical similarity of the two elements expressed by the z/r ratio (charge/ radius ratio), the z/r ratio is 2.02 for calcium ions Ca2+ and 2.06 for cadmium Cd2. Separateted nanoparticles of calcium carbonate obtained by burning eggshells (727°C) with dimensions from 100 to 200 nm and a specific surface area of 3.9 m2/g showed the highest adsorption capacity of 99.8%, synthetic calcium carbonate at 71.8%, and ground eggshells the lowest at 25.0%. Designed and laboratory-tested filter system of nanoparticles - nanofibers captures 95.6% and 96.8% of cadmium ions from an aqueous solution within 10 minutes and 90 minutes, respectively, at a concentration of cadmium ions of 10 mg/l, and at several nanoparticles of 0.3 g. The ion exchange is carried out only on the filter surface, and after a specific time, the calcium carbonate nanoparticles are released from the filter probably due to absence of chemical bond between nanoparticles and nanostructures or the low density of the nanofibrous structure. SEM, EDX, FTIR, BET and TGA analysis were used for material evaluation. The adsorption capacity of used nanoparticles and filter adsorbers was evaluated according to residual amounts of cadmium ions in aqueous solutions using ICP-IOS.

Phosphoramidate functionalization of hybrid chitosan/SiO2 beads for efficient sorption of ruthenium and application on seawater as a case study

Ruthenium removal from complex solutions (highly saline effluents, seawater) is a critical challenge. Herein, the sorption capacity of chitosan/SiO2 composite beads (Ch-Si) for ruthenium nitrosyl is increased three-fold after phosphoramidate grafting (DPA-Ch-Si, 1.6 mmol Ru g−1) at pH 5. Uptake kinetics and sorption isotherms are compared at pH0: 3, 5 and 10; playing with the mode of agitation (mechanical, MA, vs. ultrasonic treatment, UT). The sorbent maintains good sorption capacities at pH 3 and 10. Uptake kinetics modeled by pseudo-first order rate equation is boosted by functionalization. For Ch-Si, sorption isotherms are modeled by the Langmuir or Sips equations (depending on the pH), while for DPA-Ch-Si the best fits depend on pH, temperature and mode of agitation. Ruthenium sorption is spontaneous and endothermic for the two sorbents. For DPA-Ch-Si, the sorption capacity increases from 1.62 to 1.70 mmol Ru g−1 to 2.23–2.32 mmol Ru g−1 (T increasing from 21 to 50 °C). Nitric acid solution (0.3 M) reveals highly efficient for back extraction; ruthenium is completely released in <15 min. The functionalized sorbent can be reused for a minimum of 10 cycles, with limited loss in performance. Phosphoramidation improves sorption selectivity for the treatment of equimolar multicomponent solutions (Na, Ca, Mg, Fe, Al, U, and Nd). The effect of pH on sorption selectivity is evaluated in simple multi-metal solutions and complex environment. In seawater, the selective recovery of ruthenium is favored at pH close to 10. These tests confirm the promising perspectives offered for ruthenium removal from complex environments. Physicochemical characterizations of the sorbent (and their modes of interaction with ruthenium nitrosyl) included SEM, BET, TGA, FTIR, XPS, and elemental analyses.

Innovative grey water treatment using eco-friendly bio-photocatalyst AgCuFe2O4@chitosan in the presence of synergistic effects of persulfate activation: optimization and mechanisms.

In this study, AgCuFe2O4@Chitosan bio-photocatalyst was synthesized to make the most of environmental benignity and chemical stability for advanced greywater applications. The photocatalyst was evaluated under UV irradiation by synergistic activation of persulfate. FESEM, EDS-Mapping, and BET analyses showed quasi-spherical nanoparticles with a homogeneous size distribution, homogenous elements dispersion, and 15.305 m2/g surface area. XRD analysis confirmed that Ag and Cu were effectively incorporated into the chitosan matrix, which increased its crystallinity and stability. The photocatalyst showed a good magnetic property with an Ms. value equal to 17.13 emu/g, which helped in its easy retrieval and reuse. The TGA analysis demonstrated that the bio-composite had high thermal stability up to 600 °C. The optimal treatment conditions were a pH of 3, 2 mM persulfate, and 0.8 g/L photocatalyst dosage, where COD removal efficiencies were 82.9 % and 73.7 %, for synthetic and natural greywater, correspondingly. During the degradation process, greywater followed a pseudo-first-order kinetic model, where both sulfate and hydroxyl radicals played key roles in the elimination of COD. Moreover, the bio-photocatalyst was very reusable up to more than a few runs of treatment cycles with very good performance, underpinning the possible applications in the greywater treatment process in a sustainable manner.

Design and construction of robust nickel-based MOFs for promoting HER catalytic activity

The proposal of the dual-carbon target has attracted widespread attention to explore hydrogen evolution reaction (HER) electrocatalysts to promote the development of clean energy. Here, we propose a strategy to form hierarchically porous electrocatalytic hydrogen evolution catalysts (MOFs I−II) by calcining prefabricated Ni-metal–organic frameworks (MOFs 1 − 2) under N2 atmosphere. Among them, three-dimensional (3D) porous MOFs 1 − 2 have been synthesized by solvothermal method based on scissor-shaped tetracarboxylic acid, named {[Ni2(L)(1,3-bit)(H2O)3](C2H3N)}n (MOF 1) and [Ni4(tib)(L)2(H2O)3(μ2-O)]n (MOF 2). Single crystal diffraction analysis shows that MOF 1 is 3,4,7-connected 3-nodes 3D framework composed of two kinds 2D planes, while MOF 2 is 2,4,7-connected 3-nodes 3D supramolecular structure constructed from 1D chains and 2D planes. As expected, SEM and BET analysis show that calcination produced a unique hierarchical micro-mesoporous structure, while the specific surface area increases by 2.3–3.8 times. The optimized MOF II exposes more active sites, accelerates electrolyte ion diffusion, and has lower electron transfer resistance, allowing it to exhibit excellent electrocatalytic HER performance in an alkaline environment. Notably, MOF II has a Tafel slope of 81 mV·dec−1 (10 mA·cm−2) with a lower overpotential (225 mV). Compared with the pristine MOF 2, the performance of MOF II is significantly improved and it can operate stably for a long time. The possible electrocatalytic HER mechanism has been investigated by density functional theory (DFT). The results are expected to provide inspiration for the rational design and development of stable and efficient MOF-based HER electrocatalysts.

Closing the Loop on Polyester: A Green Approach to Chemical Recycling with Zn[L-Proline]2 Supported Kaolin Catalyst

In present work, the depolymerization process utilizes kaolin-supported Zn[L-proline]2 (ZnP@K) as a recyclable Lewis acid catalyst, paving the way for the cost-effective production of recycled materials. The supported catalyst is characterized using FTIR, X-ray diffraction, SEM and BET analysis. The depolymerization of polyester textile waste, especially coloured threads, promoted by ZnP@K to yield more than 90% of monomers in pure form. In addition, irrespective of the colour of polyester threads, the process exhibited 100% conversion of polyester threads and obtained pure colourless monomers, bis(2-hydroxyethyl)terephthalate (BHET) and bis(2-hydroxyethyl)-terephthalamide (BHETA). The monomers are assessed for their structure and purity using FTIR, mass and NMR spectral techniques. While comparing with ZnO nanoparticles, ZnP@K depolymerized the polyester wastes in terms of yield and purity and it proved efficient and sustainable for recycling textile polyester waste.

Synthesis of magnetic Fe3O4@g-C3N4–SO3H composite and its application for the synthesis of α-amido alkyl-β-naphthols

Magnetically separable g-C3N4 composite functionalized with SO3H groups (Fe3O4@g-C3N4–SO3H) was synthesized by polymerizing melamine on commercial nano Fe3O4 to prepare magnetic g-C3N4 followed by sulfonation. Catalytic activity of this composite was checked for the synthesis of fifteen α-amido alkyl-β-naphthols under solvent free conditions. The prepared catalyst exhibited excellent activity with an appreciable yield (60–93 %) in a short duration of time (15–240 min). The catalyst was active towards wide range of aromatic, heterocyclic as well as aliphatic aldehydes. The catalyst was recovered using an external magnetic field and reused for four consecutive cycles without any appreciable loss in its catalytic activity. Physical structure of the composite was studied by SEM and TEM analysis and the crystal structure by powder XRD. Surface area and porosity were determined using nitrogen adsorption-desorption via BET analysis. Elemental composition was determined by SEM-EDS and CHNS analysis. Acidity was measured using an ammonia temperature programme desorption technique and pH determination by back titration. Functional groups were studied by FTIR and thermal stability by TGA-DTA.

Preparation of Lignin-Based Slow-Release Nitrogen Fertilizer

Slow-release nitrogen fertilizer technology is essential for sustainable agriculture, reducing field pollution and enhancing fertilizer efficiency. Lignin, a natural polymer derived from agricultural and forestry waste, offers unique benefits for slow-release fertilizers due to its biocompatibility, biodegradability and low cost. Unlike conventional biochar-based fertilizers that often rely on simple pyrolysis, this study employs hydrothermal activation to create a lignin-based slow-release nitrogen fertilizer (LSRF) with enhanced nutrient retention and controlled release capabilities. By incorporating porous carbon derived from industrial alkaline lignin, this LSRF not only improves soil fertility, but also reduces nitrogen loss and environmental contamination, addressing key limitations in existing fertilizer technologies. We studied the hydrothermal carbonization and chemical activation of IAL, optimizing the conditions for producing LSRF by adjusting the ratios of PC, IAL and urea. Using BET, SEM and FT-IR analyses, we characterized the PC, finding a high specific surface area of 1935.5 m2/g. A selected PC sample with 1923.51 m2/g surface area and 0.82 cm3/g pore volume and yield (37.59%) was combined with urea via extrusion granulation to create the LSRF product. Soil column leaching experiments showed that LSRF effectively controls nutrient release, reducing nitrogen loss and groundwater contamination, ensuring long-term crop nutrition. This research demonstrates LSRF’s potential in improving fertilizer efficiency and promoting sustainable agriculture globally.

A Study on the Mechanism by Which Graphene Oxide Affects the Macroscopic Properties and Microstructure of Abrasion-Resistant Ultra-High-Performance Concrete (UHPC)

To further enhance the abrasion resistance of UHPC in demanding abrasion environments, this study investigated the effects of graphene oxide (GO) on the workability, mechanical properties, and abrasion resistance of UHPC. Utilizing 27Al Nuclear Magnetic Resonance (NMR), 29Si NMR, microhardness, and BET analysis, the study analyzed the mechanisms through which GO influences UHPC’s microstructure in terms of abrasion resistance. Additionally, molecular dynamics simulations were employed to examine the mechanisms by which GO enhances UHPC’s abrasion resistance at the nano and micron scale. The findings show that an optimal amount of GO can improve the mechanical properties and abrasion resistance of UHPC. When 0.03% of GO (by cementitious material mass) was incorporated, the impact on workability was minimal, yet compressive strength increased by approximately 1.80%, flexural strength by 3.02%, impact wear resistance by 1.78%, the abrasion loss rate decreased by 10.01%, ultimate impact energy increased by 1.76%, and the toughness index improved by 10.10%. GO enhances abrasion-resistant UHPC primarily by increasing hydration, refining pore structure, and improving the microstructure of the interfacial transition zone. While GO increases the hydration degree of the UHPC matrix, it does not alter the silicate chain in C-A-S-H gels within the paste. Additionally, the incorporation of graphene oxide can refine the pore structure of the UHPC cement paste and improve the microstructure of the interfacial transition zone (ITZ) between the aggregate and the cement paste. The molecular dynamics simulation reveals that, under abrasive forces, GO forms strong, stable chemical bonds with the C-A-S-H base atoms, significantly enhancing the abrasion resistance of C-A-S-H.

Synthesis of a wide range of biphenyl derivatives and symmetrical sulfides, using SnFe2O4@SiO2@P-Pd MNPs as a novel, efficient, green, and reusable catalyst

We have introduced the SnFe2O4@SiO2@P-Pd catalyst for the one-pot synthesis of biphenyl derivatives and symmetrical sulfides. For this purpose, SnFe2O4 nanoparticles were modified with Phenylalanine. The synthesized catalyst underwent characterization through BET, FT-IR, SEM, XRD, ICP, TGA, VSM, and EDX analyses. This novel approach offers the advantages of a recyclable heterogeneous catalyst, which can be easily separated from the reaction mixture using an external magnet, along with shorter reaction times, high product yields, and cost-effective, environmentally friendly conditions. The SnFe2O4@SiO2@P-Pd catalyst can be reused for up to five cycles without significant loss of catalytic activity. The results indicate that SnFe2O4@SiO2@P-Pd is an effective hybrid catalyst for synthesizing biphenyl derivatives and symmetrical sulfides.

Enhanced capacitance of MXene synthesized through safer route and its composite with amino graphene oxide

Two-dimensional (2D) MXene has received a lot of attention recently due to its outstanding mechanical, electrical, and thermal stability. However, poor specific capacitance severely limits its application towards supercapacitor. Moreover, the existing hazardous synthesis route of MXene is also a concern in the scientific community. On the other hand, amino graphene oxide (AGO) has very high electrical properties yet it is thermally unstable beyond 160 °C. Therefore, the present work reports a novel composite consisting of MXene and AGO, i.e., MAC, capable of exhibiting superior electrical properties along with the elevated thermal stability. Importantly, the MXene has been synthesized by a greener technology by using a mixture of concentrated HCl and NH4F to produce HF (etching agent) in situ rather than its ex situ addition. The formation of MAC is confirmed from microscopic (FE-SEM), thermal (TGA), diffractometric (XRD), spectroscopic (FTIR and XPS), and BET analyses. The thermogravimetric (TG) result shows that there is a significant improvement in thermal stability of AGO in the MAC. Moreover, synthesized MXene using safer route and MAC shows significant improvement in specific capacitance (2084.39 F g−1 at scan rate of 5 mV s−1 in PBS buffer solution) which is approximately twice than most of the reported capacitance in the literature. The improved thermal and electrochemical properties of MXene-AGO composite enhance its the potential use as supercapacitor.

Carboxylic acid-based fuel mediated sustainable one-pot fabrication of CaFe2O4 with enhanced adsorptive elimination of hazardous dye

The present work successfully demonstrated the morphological variation of CaFe2O4 (CFO) concerning various fuels (carboxylic acid groups contain compounds) using a one-step combustion technique. The SEM analysis of the CFO suggests the formation of sharp-edge rocky crystals to highly agglomerated porous clumps concerning the role of fuel. The x-ray diffraction analysis suggests that all samples of CFO are nanocrystalline orthorhombic structure constituted <50 nm. The BET and EDX analysis discloses that CFO s surface area and element composition is highly depend on the fuel molecule (reducer). The CFO performs efficacious in the adsorptive removal of hazardous dye Acid Fuchsin (AF) from an aqueous medium in a slightly acidic environment (pH 6). The AF removal was engaged with the batch adsorption method and optimized the process’s essential parameters (amount of adsorbent, initial AF concentration, and time) were optimized to achieve the utmost efficiency. The AF adsorption was well described by the Langmuir isotherm with outstanding adsorption capacity in the order of CFO-OA (Oxalic acid) (866) < CFO-TA (Tartaric acid) (1063) < CFO-CA (Citric acid) (1504) < CFO-MA (Malonic acid) (1656 mg/g). The adsorption energies were estimated from the Dubinin-Radushkevich model, indicating that adsorption occurs via the chemical process. The pseudo-second-order (PSO) kinetic model was better at explaining the uptake of AF, and the Intraparticle diffusion model indicated that pore diffusion was the rate-controlling step. The reusability test shows that the CFO has high efficiency up to five regeneration cycles. Thus, the work suggests that CFO could be an eco-friendly, cost-effective alternative adsorbent for wastewater treatment.