INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
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IF 8.5
Shaomin Kang,Xinyu Zhang,Usama Shakeel,Jiaqi Guo,Wenyuan Zhu,Igor S. Makarov,Mohammad Rizwan Khan,Huining Xiao,Junlong Song
This study investigates amphoteric cellulose (AC) adsorption behaviors on the charged silica surface and the associated thermodynamics, a key area with broad industrial relevance. We synthesized a range of ACs with different degrees of substitution (DS) and examined their adsorption on silica using quartz crystal microbalance with dissipation monitoring (QCM-D). By applying Langmuir and Freundlich isotherm models, the maximum adsorption capacity and the interactions between ACs and silica were assessed, and then Van't Hoff equation was employed to estimate the thermodynamic parameters to unveil the mechanisms involved. In terms of ΔG°, ΔH°, and ΔS° associated with the adsorption of AC-0.23 at 298 K were assessed to be −6.68 kJ·mol −1 , 18.98 kJ·mol −1 , and 85.61 J·mol −1 ·K −1 , respectively. Accordingly, those for AC-0.56 were − 11.21 kJ·mol −1 , −10.53 kJ·mol −1 , and 1.86 J·mol −1 ·K −1 . These findings underscore the substantial influence of DS on adsorption behavior and thermodynamics of ACs due to the molecular flexibility playing a crucial role in adsorption. The low-charge-density polymer exhibits higher flexibility and entropy-driven adsorption, while the high-charge-density polymer shows stronger electrostatic interactions and more enthalpy-driven adsorption. Our research provides crucial insights into the adsorption behavior of ACs with varying DS, which is essential for enhancing their performance in industrial applications.
研究领域:
化学工程
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材料科学
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界面科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2019
·
IF 3.683
Yan Xiong,Jie Chen,Ming Duan,Xiang Li,Jun Li,Can Zhang,Shenwen Fang,Rui Liu,Run Zhang
The investigation of adsorption performance at the adsorbent surface can help to reveal the treatment mechanism and improve the treatment efficiency of adsorption technology for heavy metal ions (HMIs). This work developed a methodology to investigate the adsorption behavior of HMI Cr(VI) at the silica surface by confined near-field evanescent wave (CNFEW) measurement. A silica optical fiber (SOF) was used as the adsorption substrate and light waveguide element to integrate both Cr(VI) adsorption and CNFEW production on its surface. According to the sensitive CNFEW response, the adsorption behavior of Cr(VI) was in situ monitored and real-time evaluated. The thermodynamic information of adsorption equilibrium constant (Kads) and adsorption free energy (ΔG) and dynamic information of the apparent adsorption rate (vads) and adsorption time (tads) were obtained through Langmuir isotherm and kinetic fitting, respectively. Different reaction performances between Cr(VI) and adsorption sites were successfully differentiated, evaluated, and characterized. A site-decided-mechanism was therefore presented to describe the surface interaction process for Cr(VI), which including fast adsorption on type I Si–O– site through electrostatic attraction with and slow adsorption on type II Si–OH site through coordinative interaction with ΔGSiOH–Cr(VI)II = −26.18 kJ mol–1. The adsorption mechanism of Cr(VI) at the SOF silica surface was furthermore verified by zeta potential analysis, Fourier transform infrared investigation, and fluorescence imaging. Unlike conventional ex situ or in bulk detection, the present CNFEW-based approach targets the “localized” adsorption of Cr(VI) adsorbed to the solid adsorbent surface. Consequently, our work favorably constructs a surface platform and provides new insights on understanding the adsorption mechanism for HMIs.
研究领域:
环境科学
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材料科学
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化学
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产品关联
DOI
PubMed
高影响因子
Nanoscale Research Letters
·
2019
·Vol. 14
·期 1
·1-15
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IF 3.159
Protsak Iryna S.,Morozov Yevhenii M.,Dong Wen,Le Zichun,Zhang Dong,Henderson Ian M.
Abstract Three poly(organosiloxanes) (hydromethyl-, dimethyl-, and epoxymethylsiloxane) of different chain lengths and pendant groups and their mixtures of dimethyl (DMC) or diethyl carbonates (DEC) were applied in the modification of fumed silica nanoparticles (FSNs). The resulting modified silicas were studied in depth using 29 Si, 1 H, and 13 C solid-state NMR spectroscopy, elemental analysis, and nitrogen adsorption-desorption (BET) analysis. The obtained results reveal that the type of grafting, grafting density, and structure of the grafted species at the silica surface depend strongly on the length of organosiloxane polymer and on the nature of the “green” additive, DMC or DEC. The spectral changes observed by solid-state NMR spectroscopy suggest that the major products of the reaction of various organosiloxanes and their DMC or DEC mixtures with the surface are D (RR’Si(O 0.5 ) 2 ) and T (RSi(O 0.5 ) 3 ) organosiloxane units. It was found that shorter methylhydro (PMHS) and dimethylsiloxane (PDMS) and their mixtures with DMC or DEC form a denser coverage at the silica surface since S BET diminution is larger and grafting density is higher than the longest epoxymethylsiloxane (CPDMS) used for FSNs modification. Additionally, for FSNs modified with short organosiloxane PMHS/DEC and also medium organosiloxane PDMS/DMC, the dense coverage formation is accompanied by a greater reduction of isolated silanols, as shown by solid-state 29 Si NMR spectroscopy, in contrast to reactions with neat organosiloxanes. The surface coverage at FSNs with the longest siloxane (CPDMS) greatly improves with the addition of DMC or DEC. The data on grafting density suggest that molecules in the attached layers of FSNs modified with short PMHS and its mixture of DMC or DEC and medium PDMS and its mixture of DMC form a “vertical” orientation of the grafted methylhydrosiloxane and dimethylsiloxane chains, in contrast to the reaction with PDMS/DEC and epoxide methylsiloxane in the presence of DMC or DEC, which indicates a “horizontal” chain orientation of the grafted methyl and epoxysiloxane molecules. This study highlights the major role of solid-state NMR spectroscopy for comprehensive characterization of solid surfaces. Graphical abstract
研究领域:
材料科学
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分析化学
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DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2017
·Vol. 409
·期 9
·2401-2410
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IF 3.431
Zhang Haijuan,Qiao Xin,Cai Tianpei,Chen Jia,Li Zhan,Qiu Hongdeng
In this paper, N-doped carbon dots (NCDs) were successfully decorated on the spherical porous silica surface in deep eutectic solvents (DESs) as a novel class of green solvents. The appropriate density and hydrophility of DESs guaranteed the fine dispersibility of silica particles and NCDs, resulting in a homogeneous and thin layer of NCDs immobilization. As compared with traditional organic solvents (DMF and THF), higher surface coverage was obtained in the medium of DES, proving its feasibility as a new kind of alternative solvent for hydrophilic nanomaterial-based surface modification of silica spheres. The resulting NCDs-decorated silica particles (Sil-NCDs) were characterized in detail and packed into chromatographic columns to study their initial feasibility as adsorbent material for liquid chromatography. The resultant packing materials demonstrate a selective behavior for polar compounds in hydrophilic interaction liquid chromatography (HILIC) mode. This work gives a typical example of using carbon dots as stationary phase component, and such material is hopeful to be used in other research fields such as solid absorbents, recycling catalysts, and solid-state electrochemistry etc.
N-doped carbon dots (NCDs) were successfully coupled on the surface of porous silica spheres in a green strategy using deep eutectic solvents (DES) as media for HILIC.
研究领域:
分析化学
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材料科学
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色谱技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2022
·
IF 4.331
Yali Yang,Juanjuan Wang,Ruirui Liu,Kaijun Quan,Jia Chen,Xiuhui Liu,Hongdeng Qiu
Surface modification is an effective way to functionalize the materials so as to get some special properties. Tetraphenylethylene (TPE) has been widely investigated as a well-known reagent which has the nature of aggregation-induced emission (AIE), but has never been reported in the liquid chromatography stationary phase. In this work, TPE-grafted silica (Sil-TPE) was obtained successfully using the derivative of 1-(4-hydroxyphenyl)-1,2,2-triphenylethylene as a ligand, and then characterized by elemental analysis, Fourier transform infrared spectra, thermogravimetric analysis, and so forth. Laser scanning confocal microscopy images reflected the AIE phenomenon of grafted TPE because the internal vibration and rotation of TPE molecules were restrained in the confined silica space. The contact angle test showed superhydrophobic properties of Sil-TPE. In order to understand thoroughly the mechanism of chromatographic performance and retention behavior for Sil-TPE, Tanaka test mixture, alkylbenzenes, polycyclic aromatic hydrocarbons (PAHs), and phenols were separated. This reveals that Sil-TPE has strong aromaticity and certain shape selectivity, especially, has excellent separation performance for PAHs and phenols. The thermodynamic properties and repeatability of Sil-TPE were further studied, which showed the stability of Sil-TPE. This work shows that TPE can be successfully grafted on silica surface and it has the potential to be a new kind of promising stationary phases in the future.
研究领域:
材料科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
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2018
·
IF 4.439
Lijuan Chen,Xiaohui Guo,Zhixin Jia,Yuhan Tang,Lianghui Wu,Yuanfang Luo,Demin Jia
A solid-phase preparation method was applied to obtain a novel, green and effective functional nanoparticle, silica-supported sulfur monochloride (silica-s-S 2 Cl 2 ), by the chemical reaction between chlorine atom and silicon hydroxyl on the silica surface. Through this chemical reaction, silica surface supported with high content of sulfur, and the functional nanoparticles can not only vulcanize the rubber instead of sulfur or other vulcanizing agent with high performance, but also improve the filler-rubber interaction as a modifier due to the improved modification effect. 29 Si NMR, Raman spectroscopy, Element analysis and TGA confirm that the sulfur monochloride is chemically bonded on the silica surface. Cure properties measurement, morphology of filler dispersion, mechanical properties measurement, immobilized polymer layer and oxidation induction time increment together show that the novel vulcanizing agent silica-s-S 2 Cl 2 instead of sulfur in rubber vulcanization gives rise to significant improvement in the crosslinking density and the interfacial adhesion between silica particles and the rubber matrix, which is on account of the promoted vulcanizing on the functional silica nanoparticles surface with the supported sulfur.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Fang Cheng,Hanqi Wang,Wei He,Bingbing Sun,Jing Zhao,Jingping Qu,Qing Wang
This article demonstrates the catalytic oxa-Michael reaction of inorganic silanol groups with vinyl sulfones, which facilitates an efficient strategy for functionalization of the silica surface. The strategy was applied on materials ranging from nanoscale to macroscale silica, and the surface functionalization was achieved in hours using organo-catalysts at mild temperature. The formation of Si–O–C bonds on the surface was characterized by solid-state 13C cross polarization-magic angle spinning nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Our strategy showed several advantages over traditional methods, and the resulting Si–O–C bond exhibited distinct behaviors toward different solvents. Organic solvents would stabilize the functionalized silica materials, while aqueous solutions would result in degradation affected by both solution and surface factors. With use of divinyl sulfone as a cross-linker, a variety of molecules can be immobilized and sequentially released in a controllable manner, which would benefit a broad range of applications from sensing to drug and catalyst carriers.
研究领域:
材料科学
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化学工程
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2019
·
IF 4.63
Jieyu Wang,Zhen Guo,Jun Zhao,Qingqing Yang,Yihu Dai,Yanhui Yang,Chuan Wang
The application of continuous flow reactor in the synthesis of materials with controlled properties has attracted significant attentions in recent years. In this work, we demonstrated that surface functionalities of silica can be tuned with the aid of a segmented continuous flow reactor (SCFR). Infrared spectra showed that silica surface had a variety distribution of silanol groups which were controlled by the continuous flow technique. These silica samples were studied as Pd-based catalysts supports. A correlation between surface silanol groups and the growth of Pd metal nanoparticles were constructed with the aid of operando X-ray diffraction technique and scanning transmission electron microscopy. Solvent free aerobic oxidation of benzyl alcohol to benzyl aldehyde was employed to investigate the catalytic performances of these catalysts.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
Analytical Methods
·
2018
·Vol. 10
·期 45
·5387-5397
·
IF 2.073
Chunmiao Bo,Xiaojun Dai,Weimin Chen,Rui Cao
Selectivity is very important for stationary phase applications. However, selectivity is usually quite difficult to adjust once the ligands are fixed. Departing from the reported methods, dodecyl methacrylate (DOMA) and hydroxyethyl methacrylate (HEMA) were grafted onto a silica surface via two-step surface initiated-atom transfer radical polymerization (SI-ATRP) to synthesize reverse-phase/hydrophilic interaction mixed-mode stationary phases. The grafted amounts of C12 and OH functional groups were controlled by varying the ratios of DOMA to HEMA in the polymerization system. The resulting stationary phases were characterized by transmission electron microscopy (TEM), solid-state 13C NMR spectroscopy, elemental analysis (EA), Fourier transform infrared (FT-IR) spectrometry, and thermogravimetric analysis (TGA). The chromatographic performance and separation selectivity of the packed columns were investigated in different chromatographic modes using a wide range of analytes, including a non-polar benzene series, moderately polar β-agonists as well as organic acids, and strongly polar nucleosides. Exceptionally, the retention of the tested analytes displayed an obvious dependence on the ratio of the two functional monomers in the polymerization. In conclusion, the proposed strategy for the development of a mixed-mode chromatographic stationary phase can provide flexible selectivity by simply tuning the ratios of functional monomers.
研究领域:
分析化学
·
色谱技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）