Vietnam Journal of Catalysis and Adsorption

Development and Multi-Objective Optimization of Cosmetic Cream Formulations Using Artificial Neural Networks and Genetic Algorithms

2026-01-11T03:09:10+07:00

In recent years, demand for herbal cosmetics has grown due to their safety, efficacy, and eco-friendliness. Yet, herbal skincare formulations often lack standardization, leading to variable quality. This study focuses on developing and optimizing a herbal moisturizing cream using artificial intelligence (AI) in formulation design. Fourteen natural ingredients, including aloe vera, shea butter, almond oil, hyaluronic acid, and essential oils, were combined into 30 experimental formulations through a Simplex Lattice mixture design. Key properties—pH, viscosity, permeation, and moisturizing ability—were measured and modelled using a fuzzy logic neural network integrated with a genetic algorithm. The optimal formula was then evaluated for texture, absorption, spread ability, and stability. Integrating I(14)-HL(2)-O(4) with genetic algorithms highlights an effective approach for standardizing and optimizing herbal cosmetic formulations, offering a scientific basis for creating high-quality, consistent skincare products.

Study on the preparation and evaluation of additive systems for extending the thickening time of well cement for application in oil and gas drilling operations

2026-01-11T23:19:49+07:00

The article investigates the relationship between the characteristic structure and application performance of a thickening-time retarding additive for cement slurries and cement stones used in oil well cementing. SEM images show a more uniform microstructure, while XRD indicates that the α-SiO₂ peak at 2θ ≈ 26.6° remains clear, and the Ca₃SiO₅ peak appears with higher intensity, reflecting a retarded hydration process due to the additive. FT-IR spectra reveal absorption bands similar to commercial samples, with slight shifts. Particle size analysis shows a finer and more uniform system: D50 decreases from 25.259 µm to 17.101 µm, and the most frequent particle size decreases from 31.982 µm to 21.393 µm.

In terms of application, the additive prolongs the slurry thickening time to 6 hours 58 minutes at 0.10 gps, remaining stable under high temperature and pressure. Permeability is nearly unchanged, while porosity improves (21.023% vs. 22.604%). The maximum compressive stress increases, indicating better load-bearing capacity and stability, confirming the additive’s practical effectiveness.

Brønsted Acid- Functionalized Carbon from Mangosteen Peel for Catalytic Conversion of Carbohydrates to 5-hydroxymethylfurfural

2026-01-11T23:30:49+07:00

A low-cost and efficient solid Brønsted acid catalyst was successfully synthesized by sulfonating a carbon substrate derived from mangosteen peel, denoted as PC-SO₃H. This bio-based carbon material, after functionalization with –SO₃H groups, was employed as a heterogeneous catalyst for the conversion of fructose into 5-hydroxymethylfurfural (HMF), an important platform compound in the production of furan-based derivatives. The reaction was conducted at 120 °C for 2 hours, yielding an HMF selectivity of up to 71.6%. In addition, reaction parameters were investigated to evaluate their influence on conversion efficiency and product selectivity. The study results demonstrated that PC-SO₃H not only exhibited high catalytic performance but also showed promising potential for practical application in biomass-based chemical synthesis processes due to its reusability. Based on experimental data and catalyst characterization techniques, including FTIR, Raman, SEM-EDX, a reaction mechanism was proposed for the dehydration of fructose catalyzed by PC-SO₃H.

Study on the production of silver nanoparticles from plant extracts for application in stimulating maize seed germination

2026-01-11T23:46:15+07:00

Silver nanoparticles are among the widely applied nanomaterials due to their strong antibacterial properties and effective ability to eliminate fungi and bacteria. In agriculture, silver nanoparticles are being studied as a potential alternative to chemical pesticides, contributing to enhanced productivity and biosafety. The green synthesis method with the aims to save cost and minimize chemical during silver nanoparticles production protecting the environment. Among various plant extracts, Terminalia catappa leaf extract was selected as a suitable reducing agent for the synthesis of silver nanoparticles. Silver nanoparticles were successfully synthesized from terminalia catappa leaf extract, and their structural morphology was evaluated by modern techniques such as SEM, XRD, and FTIR, yielding a spherical silver nanoparticles shape with an average diameter ranging from 20 to 100 nm. The study also investigated the impact of synthesis conditions on the germination of maize seeds, with the optimal conditions 0.005M AgNO₃ concentration, synthesis temperature of 40˚C, and reaction time of 30 minutes that resulted in the highest germination rate and seed vigor index. Maize seeds treated with a diluted silver nanoparticle solution at concentrations of 4-6 times showed the ability to stimulate germination, providing a high germination rate and vigor index, with uniform development of the seeds.

Selection of Working Electrodes for the Electrochemical Determination of Ammonium and Nitrate in Aquaculture Water

2026-01-12T04:18:52+07:00

This study presents the selection and evaluation of ammonium and nitrate working electrodes for integration into a multifunctional electrochemical system to determine these parameters effectively. The electrochemical method employing selected ammonium and nitrate electrodes was evaluated based on key analytical parameters, including repeatability and the linear correlation between potential U (mV) and lgC (ppm) for both ions. The research results showed that, the calibration curve for lgC_NH4+ (mg/L) versus potential U (mV) was described by the equation y = 0.6280x + 1.353, with a regression coefficient R² = 0.997; limit of detection (LOD) = 0.2922 mg/L; and limit of quantification (LOQ) = 0.8766 mg/L. The calibration curve for lgC_NO3- (mg/L) was y = 0.5420x + 2.067, with R² = 0.996; LOD = 0.3495 mg/L; and LOQ = 1.0485 mg/L. The method demonstrated suitable detection and quantification limits for monitoring and providing rapid feedback on parameter fluctuations. Measurement accuracy was further validated through comparison with reference methods. Comparison with reference methods showed no significant differences between analytical approaches. Real-time, on-site electrochemical measurements conducted in aquaculture environments confirmed the suitability of the integrated sensors. All measured parameters were within permissible thresholds for freshwater aquaculture, demonstrating the practical utility and reliability of the system.

Investigation of the Ni(II) adsorption isotherm onto biochar derived from cassava stem

2026-01-12T04:24:57+07:00

In this study, biochar was synthesized from Cassava stem via a pyrolysis at 700 ^oC within 60 minutes. This biochar was used as an adsorbent to remove Ni(II) from an aqueous solution. Effects of pH, adsorption time, and initial concentration of Ni were investigated. Results showed that the adsorption of Ni(II) onto biochar derived from Cassava stem obtained the maximum at pH = 8 and adsorption time = 1080 min with maximum adsorption capacity calculated from Langmuir of 31.77 mg/g. Isotherm and kinetic studies indicated that the Sips model gave the best fit with experimental data. This study shows the potential application of Cassava stem biochar on the treatment of polluted Ni(II) wastewater.

Synthesis, photophysical characterization, aggregation-induced emission effect and crystal structure of (E)-butyl-3,3'-(5,6-dicarbazolylbenzo[c][1,2,5]thiadiazolyl)acrylate

2026-01-12T04:29:07+07:00

In this study, we report the development of a simple and highly efficient synthetic protocol for the preparation of novel (E)-butyl-3,3'-(5,6-dicarbazolylbenzo[c][1,2,5]thiadiazolyl)acrylate via Heck cross-coupling reactions catalyzed by palladium. Optimized conditions utilizing a Pd(OAc)₂/K₂CO₃ system afforded high yields (70%), resulting in the successful synthesis and characterization (¹H-NMR, ¹³C-NMR) of a new compound. Detailed investigations into its photophysical properties revealed pronounced aggregation-induced emission (AIE) behavior. Single-crystal X-ray diffraction analysis provided insights into the molecular packing and structure–property relationships, while computational chemistry supported the understanding of its electronic features. This work presents a valuable contribution to the field of C–C cross-coupling chemistry, offering a practical and versatile approach for the synthesis of diverse 4,7-dialkylated-5,6-N,N-dicarbazolylbenzothiadiazole derivatives, with potential applications in medicinal chemistry and materials science.

Production of activated carbon from bamboo chopsticks and its application in methylene blue adsorption

2026-01-12T04:32:03+07:00

Activated carbon from bamboo chopsticks (BCAC) was prepared via hydrothermal pretreatment with 3.5% H₂SO₄ followed by KOH activation. Pretreatment reduced lignin, ash, and moisture while enriching cellulose, hemicellulose, and total carbohydrates. The optimal activation condition was 800 °C for 120 min, yielding a BET surface area of 397.6 m²/g and micropores with an average size of 1.2 nm. XRD, SEM, and FT–IR confirmed the structural transformation from cellulose-rich biomass to amorphous carbon, characterized by the emergence of graphitic domains and oxygenated functional groups. MB adsorption performance was strongly pH-dependent, enhanced above the pHpzc (3.4). Kinetic analysis revealed that the pseudo-second-order model provided the best description of the process, indicating chemisorption with multi-step diffusion. The Langmuir isotherm provided the best fit, with a maximum adsorption capacity of 54.95 mg/g. FT–IR after adsorption revealed multiple interaction mechanisms, including electrostatic attraction, π–π stacking, hydrogen bonding, and van der Waals forces. Desorption studies indicated ethanol was more efficient than HCl in regenerating BCAC, and reusability tests showed stable performance over two cycles before declining. These findings highlight BCAC as a promising, low-cost adsorbent for dye removal, demonstrating potential for wastewater treatment applications.

Facile synthesis of ultrasmall Bi2O3 nanoparticles for computed tomography imaging

2026-01-12T04:39:08+07:00

Ultrasmall bismuth oxide nanoparticles (Bi₂O₃ NP) are emerging as promising CT contrast agents owing to their high atomic number, strong X-ray attenuation, and versatile surface chemistry. Herein, we report a facile one-pot polyol synthesis of Bi₂O₃ NPs using triethylene glycol and polyacrylic acid (PAA), which acts as both surfactant and biocompatible coating. The obtained Bi₂O₃@PAA NPs exhibit an average core size of ~4.4 nm, uniform dispersion, and excellent aqueous stability. Their structural and surface characteristics were comprehensively confirmed by TEM, XRD, DLS, FTIR and TGA analyses. In vitro CT imaging experiments demonstrated that Bi₂O₃@PAA NPs produced a linear and concentration-dependent enhancement in Hounsfield units (HU), achieving an X-ray attenuation efficiency significantly higher than that of the commercial iodine-based contrast agent iobitridol under identical conditions. These findings highlight the potential of ultrasmall Bi₂O₃@PAA NPs as next-generation CT contrast agents.

Novel preparation of FeS2/g-C3N4 as enhanced anode materials for LIB

2026-01-12T04:42:37+07:00

This study presents a facile one-step synthesis of FeS₂/g-C₃N₄ composites at various temperatures (FSCN-T) for lithium-ion battery anodes. Structural analysis (XRD, FTIR, SEM, EDS) confirmed the successful formation of both phases, with nano-sized FeS₂ uniformly distributed on the g-C₃N₄ matrix. Electrochemical testing revealed that the FSCN-550 sample delivered optimal performance, maintaining a discharge capacity of ~240 mAh/g after 300 cycles with a Coulombic efficiency above 99%. This enhanced stability and capacity are attributed to a robust composite structure and limited g-C₃N₄ decomposition at the optimal temperature. The results position FSCN-550 as a promising high-performance anode material.

In situ Growth of Nickel Ferrite Nanoparticles on MXene as High Performance Electromagnetic Wave Absorber in X-Band

2026-01-12T04:47:25+07:00

Ti₃C₂T_x MXene sheets - a two-dimensional material with large surface area and high conductivity – show promise in electromagnetic wave (EMW) absorption, however, achieving strong and efficient absorption of electromagnetic waves in the X-band region still faces many challenges. Here, nickel ferrite nanoparticles were grown in situ on the surface and introduced into the interlayers of MXene sheets through a facile co-precipitation combined with heat-reduction . Interestingly, the minimum reflection loss (RL_min) of the NiFe₂O₄/MXene composite was -13.3 dB, indicating much stronger EMW absorption properties than pure MXene nanosheets (RL_min= -7.03 dB) at the same loading. The presence of NiFe₂O₄ nanoparticles primarily accounts for the prevention of MXene nanosheets from self-stacking, thereby enhancing conduction loss.. In addition, the presence of MXene promotes the growth and organization of nickel ferrite nanoparticles, resulting in enhanced crystal structure and surface effect between nanoparticles and MXene sheets throughout the composite. More importantly, the magnetic loss generated by the magnetic NiFe₂O₄ nanoparticles is beneficial for good impedance matching, allowing more EMW to enter the composite for dissipation. This study opens up a promising approach to enhance the absorption properties of X-band electromagnetic waves.

Gram-scale nucleophilic aromatic substitution of 4,7-dibromo-5,6-difluoro-[2,1,3]-benzothiadiazole for Synthesis of 4,7-dibromo-5,6-BINOL-O-benzo[2,1,3]thiadiazole, and 4,7-dibromo-5,6-dicarbazol-N-ylbenzo[2,1,3]thiadiazole. The Stille coupling reaction a

2026-01-12T04:50:22+07:00

In this study, we delveloped a simple and efficient synthetic procedure for the nucleophilic substitution of 4,7-dibromo-5,6-diflourobenzo[2,1,3]thiadiazole with diols, diamines and carbazole to obtain 4,7-dibromo-5,6-dinucleophile-benzo[2,1,3]diadiazole derivatives. The chiral version of BINOL and BINAM, based on (R-/S-) atropisomers of binaphthyl, were employed as nucleophilic reagents under bases (DBU 1,8-diazabicyclo[5.4.0]undec-7-ene and/or K2CO3). The nucleophillic carbazol-N-yl sodium species were synthesized via recrystallized and subsequent treatment in dried DMF and in the presence of strong base as NaH. All three nucleophiles participated successfully in the SnAr reaction, affording excellent yields with BINAM and quantitative yields with carbazole and BINOL.

Surface modification of TFC-PA membrane using α-MnO2/UiO-66-NO2 for enhancing filtration performance

2026-01-12T04:52:16+07:00

In this study, α-MnO₂/UiO-66-NO₂/TFC-PA composite membranes were successfully synthesized by immobilizing α-MnO₂/UiO-66-NO₂ onto the outermost surface of polyamide selective layer of TFC-PA membrane during the interfacial polymerization process. The membranes were characterized using techniques such as XRD, ATR-IR, EDX, SEM and contact angle measurements. The filtration performance was evaluated using a 1000 ppm NaCl solution. Various factors affecting separation efficiency were also investigated, including polymerization time, temperature, oxide loading, and composite material content. The experimental results exhibited the successful synthesis of both α-MnO₂/UiO-66-NO₂ and the α-MnO₂/UiO-66-NO₂/PA membrane. The modified membrane possessed a water flux three times higher than the pristine membrane and over 8% increase in salt rejection. In addition, the modified membrane maintained a high selectivity after long time of filtration.

Electrochromic Properties of Dibenzyl Viologen on ITO electrode: Influence of Concentration and Electrode Potential

2026-01-12T04:54:57+07:00

Viologen-based electrochromic materials have garnered significant attention due to their promising applications in nanoelectrochromic devices. The electrochromic properties of these materials such as switching time, durability, and overall device performance can be modulated by factors including counter ions, functional groups, precursor concentration, and applied potential. In this work, the electrochemical and electrochromic behaviors of dibenzyl viologen (DBV) ultrathin films deposited on conductive indium tin oxide (ITO) substrates were investigated in acidic media. The study focused on the effects of DBV concentration and applied potential, employing a combination of cyclic voltammetry (CV), chronoamperometry (CA) and atomic force microscopy (AFM). The results demonstrate that the color of ITO/DBV films in acidic environments can be reversibly tuned by varying the applied potential. The color intensity increases with higher DBV²⁺ concentrations in the solution phase. These findings highlight the potential of the DBV molecule as an effective organic electrochromic material for use in smart devices.

Large-scale synthesis of ZIF-94 with large specific surface area from zinc chloride

2026-01-12T04:59:13+07:00

ZIF-94 is a zeolitic imidazolate framework with a sodalite structure. The pore system in ZIF-94 is formed from Zn²⁺ tetrahedra linked together through imidazole 4-methyl-5-imidazolecarboxaldehyde, similar to the linkage of SiO₄^– and AlO₄^– tetrahedra in zeolites. ZIF-94 contains acid and base sites, the pore diameter is about 0.3 nm connected to large cavities of 0.91 nm. Therefore, ZIF-94 is considered a new generation advanced material with great potential for applications in catalysis and adsorption. Up to now, synthesized ZIF-94 has a low specific surface area, there has been no report synthesizing ZIF-94 from ZnCl₂ on a large-scale. Therefore, this paper presents the first research results on the synthesis of ZIF-94 with the highest specific surface area (BET) reaching 1.128 m²/g, and is also the first time to report the synthesis results of ZIF-94 from ZnCl₂ on a large-scale. ZIF-94 exhibits a crystallinity of 100%, an average crystal size of 85 nm, thermal stability up to 280 ^oC, and a yield of 73%.

Removal of azo dye in water using novel adsorbent based on rice husk biochar with surface modification by protein

2026-01-12T05:01:44+07:00

In the present study, rice husk biochar was modified with protein lysozyme to enhance the removal of toxic organic dye, Acid Orange 7 (AO7) in water. Surface modification of rice husk biochar with lysozyme increased the removal efficiency of AO7 significantly compared with bare biochar. The maximum removal of AO7 using lysozyme modified biochar exceeded 97.9% at pH 3. Adsorption isotherms of AO7 were in good agreement with Langmuir model while adsorption kinetics were well fitted by pseudo-second- order model. Under selected conditions, adsorption capacity of AO7 on lysozyme modified biochar reached 24.63 mg/g. The adsorbent was applicable for regeneration with high efficiency of greater than 80%. The removal efficiencies of AO7 in actual water samples were higher than 75%. Our study highlights the potential of bio-adsorbent based on protein modified for removal of organic dye from water environment.

Some applications of green synthesis CuNPs using wild apple (ziziphus mauritiana) leaves extract

2026-01-12T05:04:12+07:00

For the first time, copper nanoparticles were successfully green synthesized via Cu(II) reduction by using wild apple (Ziziphus mauritiana) leaf extract (CuNPs-WAE). The synthesized CuNPs-WAE were characterized by some modern techniques: XRD, FTIR and SEM. The results showed that, the predominant crystalline phase was metallic Cu, accompanied by minor Cu₂O impurities, the particles formed slightly agglomerated with dimensions 50-70 nm in width and 80-200 nm in length, surface functionalization was attributed to phytochemicals present in the wild apple leaves extract. CuNPs-WAE exhibited significant cytotoxicity against liver cancer cells, achieving an 85% inhibition rate at a concentration of 128 µg/mL. CuNPs-WAE also exhibites notable photocatalytic activity under sunlight, strongly influenced by the type of dye and Cu concentration. After 120 minutes of exposure, degradation efficiency for rhodamine B and methylene blue reached 97.5 % and 99.0 %, respectively, whereas direct red only reached 69.0 %. The photocatalytic degradation followed the pseudo-first-order reaction kinetics, mainly due to the activity of the superoxide radicals (*O₂^-). Photocatalytic activity decreases slightly during regeneration and reuse.

Synthesis of AgNPs@aerogel cellulose material from sugarcane bagasse for antibiotic removal in water: Kinetic evaluation and process optimization

2026-01-12T05:07:19+07:00

Antibiotic contamination has emerged as a critical global concern due to the excessive use of pharmaceuticals in medicine and livestock production, leading to their persistent accumulation in aquatic environments. Conventional treatment methods often show limited efficiency, high cost, or environmental drawbacks, highlighting the urgent need for sustainable alternatives. In this study, a green, porous AgNPs@cellulose aerogel composite was successfully synthesized using purified cellulose from sugarcane bagasse and lotus leaf extract as a natural reducing agent for silver nanoparticle formation. The structural and physicochemical properties of the materials were thoroughly characterized by XRD, SEM, BET, and UV–Vis analyses. XRD results confirmed the incorporation of crystalline AgNPs within the cellulose matrix, while SEM images revealed a well-preserved porous network with uniformly dispersed nanoparticles. BET analysis showed an increase in specific surface area from 70 to 87.2 m²/g after silver loading, indicating enhanced porosity. The optical band gap decreased with increasing AgNP content, demonstrating improved visible-light absorption capacity. Photocatalytic experiments showed that the AgNPs@cellulose aerogel exhibited significantly enhanced tetracycline (TC) degradation under visible light, achieving up to 95% removal under optimal conditions. Kinetic studies revealed that the TC degradation followed pseudo–first-order kinetics with high correlation coefficients (R² > 0.96). The photocatalyst also demonstrated excellent reusability, maintaining over 85% efficiency after four cycles. These findings highlight the potential of AgNPs@cellulose aerogel as an effective, eco-friendly, and sustainable photocatalyst for antibiotic removal from wastewater.