CHEMICAL PHYSICS LETTERS
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2020
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IF 2.029
Xuefeng Liu,Guo Feng,Jianmin Liu,Feng Jiang,Ting Chen,Jian Liang,Lifeng Miao,Weihui Jiang
The monolayer flake-like zirconia was prepared by a clean molten salt method, which does not require any adsorbent and template. The effects of NaOH on the composition, morphology and structure of zirconia were studied by XRD, IR, Raman, FE-SEM and TEM. The nanostructures synthesized under 2 wt% NaOH exhibit definite flake-like geometry with a large percentage of (0 0 1) plane, which measure approximately 1.8 μm long and 80 nm thick. This concomitant phase and morphology change originate from the martensite transformation of metastable tetragonal zirconia. The as-prepared zirconia sheet has potential utility in fields as diverse as chemical adsorption and photocatalysis.
研究领域:
材料科学
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化学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2026
·Vol. 37
·期 16
·1229
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IF 3.2
Xu Bing,Zhang Jian,Zeng Fanen,Pang Jiaxi,Yang Qinyi,Wu Xin,Sun Zhidong,Yu Hongbo
Biomass-derived porous carbons are considered promising supercapacitor electrodes owing to their sustainable precursors, cost-effectiveness, and superior structural features. Using bamboo shoot shells (BSSs) as the precursor, BSS-derived porous carbon was synthesized through a NaOH-assisted hydrothermal process and subsequent activation in air. The impact of hydrothermal temperature and duration on the material’s physicochemical characteristics and subsequent supercapacitor performance is methodically examined in this work. The as-prepared sample (BSSN-160–10) delivers a high specific capacitance of 211.4 F·g −1 at a current density of 1 A·g −1 , demonstrating exceptional electrochemical performance. Retaining 101% of its capacitance over 30,000 cycles, the symmetric supercapacitor yields an energy density of 15.15 Wh·kg −1 at a power density of 500 W·kg −1 . High energy density, high power density, and exceptional cycling longevity are all achieved by BSS-derived porous carbon in supercapacitor electrodes. Thus these materials offer a compelling candidate solution for green energy storage.
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DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2024
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IF 5.6
Tiancheng Xiong,Haohao Wang,Haoyang Sun,Jing Zhao,Maoning Li,Qingyuan Du,Dandan Li,Yu Nan,Zhi Zhang,Dazhi Sun
Coir fibers are commonly subjected to alkali treatment to eliminate impurities and tune their mechanical properties. However, this process can damage the fibers’ microstructures, posing a challenge in significantly enhancing both strength and toughness simultaneously. Herein, we successfully enhanced both strength and toughness of coir fibers through a combined treatment with NaOH and sodium alginate aqueous solution. Coir fibers treated with 5 wt% NaOH solution, followed by 0.5 wt% sodium alginate solution, exhibit a tensile modulus of 2475.0 MPa, a tensile strength of 126.4 MPa, and a toughness of 30.7 MJ/m³, representing improvements of 57.1 %, 72.7 %, and 116.2 %, respectively, compared to the raw fibers. Mechanistic studies revealed that NaOH treatment effectively removes pectin, hemicellulose and lignin from coir fibers but introduces numerous defects. Sodium alginate can repair these defects by forming hydrogen bonds with the rich oxygen-containing group of coir fibers. The combined treatment also increases the crystallinity of coir fibers from 30.3 % for the raw fibers to 44.1 % by removing a large number of amorphous substances. Additionally, the combined treatment reduces the microfibril angle from ∼63.6° to ∼46.6° by elongating the helix structure and filling the gaps between helical fibers. Our cost-effective strategy not only promotes the applications of coir fibers but also provides guidance for the modification of other natural plant fibers.
研究领域:
材料科学
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植物学
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DOI
高影响因子
Coatings
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2022
·Vol. 12
·期 5
·578
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IF 3.236
Su Pan,Xiaohua Tu,Jianxing Yu,Yang Zhang,Chengping Miao,Yaling Xu,Rui Fu,Jiayou Li
The optimization of NaOH-Na2SiO3-Na2B4O7electrolyte for the plasma electrolytic oxidation of AZ31B magnesium alloy was investigated through orthogonal tests. The properties of the anodized films were evaluated by film thickness, roughness measurements, salt spray tests, scanning electron microscopy (SEM), X-ray diffraction (XRD) and potentiodynamic polarization tests, respectively. The orthogonal tests revealed that the optimal formulation of the electrolyte comprised NaOH 45 g/L, Na2SiO350 g/L, and Na2B4O790 g/L. NaOH exhibited the most significant effect on film thickness, while Na2SiO3had the greatest effect on corrosion resistance. Moreover, the optimal electrical parameters were also obtained with the values of current density 1 A /dm2, oxidation time 15 min, pulse frequency 200 Hz and duty cycle of 10%. The surface morphology of the anodized coating formed under optimal conditions was uniform and compact. Furthermore, the phase compositions of all samples were mainly composed of MgO and Mg2SiO4. The corrosion potential, corrosion current density and polarization resistance of the prepared coating by plasma electrolytic oxidation improved remarkably compared with that of the substrate.
研究领域:
材料科学
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表面工程
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腐蚀与防护
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电化学
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DOI
高影响因子
CELLULOSE
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2021
·Vol. 28
·期 9
·5421-5431
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IF 5.044
Qiao Liangzhi,Liang Chao,Du Kaifeng
Carbon nanotubes (CNTs) have been proposed as next-generation lightweight structural materials, yet their application is facing challenges due to the poor dispersity in most solvents, especially in aqueous solution. Here, we report a facile and robust strategy for the rapid and scalable preparation of homogeneous and stable CNT dispersion assisted by cellulose in NaOH/thiourea aqueous solution. The whole process only needs a mild stirring procedure at ice-bath without any pre-treatment of raw materials. It is demonstrated that the suitability of the CNT dispersion for aqueous self assembly of various functional materials, ranging from zero-dimensional (0D) microsphere to three-dimensional (3D) monolith through various molding techniques. Also, the CNT dispersion can be used as ink to prepare CNT-based paper and textile through simply dyeing commercial filter paper and textile, and to directly write on the paper by syringe, indicating the great potential for flexible and wearable devices.
研究领域:
材料科学
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纳米技术
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化学工程
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
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2021
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IF 5.03
Kai Qi,Zhenzhen Jin,Dan Wang,Zhenyu Chen,Xingpeng Guo,Yubing Qiu
The irreversible electroactivity degradation is a key and broad issue for conducting polypyrrole (PPy). PPy degradation involves chemical and electrochemical processes affected by various factors, including doping anions, electrolyte pH, dissolved oxygen (DO), temperature ( T ), electrode potential, etc. This study probes into the effect of T on electroactivity degradation of PPy in 0.5 M NaOH. Increasing the T (25~80 o C), the degradation kinetics of PPy remains the same first-order relationship, while the degradation rate constant is significantly affected, which shows a maximum value in 50 o C deaerated or 70 o C aerated NaOH, respectively. In deaerated NaOH, the open circuit potential of PPy becomes very negative to reach a reduction state with increasing T , which may restrain penetration of OH - ions into PPy film to inhibit the degradation in its interior. In aerated NaOH, the concentration of DO lowers with increasing T to suppresses the electrochemical process in PPy degradation and decrease its degradation. DO still plays a crucial role in the PPy degradation process at high T . A thorough understanding of the effect of electrolyte T on electroactivity degradation of PPy would offer valuable concepts for in-depth and comprehensive insights into the mechanisms and kinetics of PPy degradation.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
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2022
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IF 4.383
Cheng Wang,Jiale Yu,Kai Feng,Huidong Guo,Lipeng Wang
In this study, natural clinoptilolite was treated with NaOH solutions of different concentrations under mild ambient conditions. The composition and structure of the as-prepared samples were characterized, and their performance was assessed in terms of the removal of the heavy metal ions Cd 2+ , Cu 2+ , and Cr 3+ from the aqueous solution. The results showed that the composition, structure, and capability of removal of heavy metal ions of the samples were significantly influenced by the NaOH concentrations. The crystal structure of clinoptilolite remained invariant under a relatively low NaOH concentration (≤0.5 M), began transforming into zeolite Na–P under a medium NaOH concentration (∼1.0 M), and then completely transformed into it under a high NaOH concentration (2.0–4.0 M). The samples treated with NaOH had lower SiO 2 /Al 2 O 3 ratios, and were superior to unmodified natural zeolite in removing the heavy metal ions. This method of treatment with relatively high concentrations of NaOH is a simple and effective way to transform natural clinoptilolite into the zeolite Na-P rich ion exchanger, which is suitable for removing heavy metal ions.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Molecular Catalysis
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2025
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IF 4.9
Lei Xia,Fang-Jing Liu,Meng-Jie Wang,Han-Bing Zhang,Jing Zhang,Yao Lu,Le-Le Qiu,Xian-Yong Wei,Yun-Peng Zhao
Production of cyclohexanone through selective hydrogenation of phenol under mild conditions has attracted much attention. Herein, a NaOH-modified Pd/WO 3 rich in oxygen vacancies for selective hydrogenation of phenol was prepared through impregnation method. The highest catalytic activity was exhibited on NaOH-Pd/WO 3 with 25 wt % addition of NaOH, and phenol achieved 100 % conversion at 90 °C and 0.7 MPa H 2 for 2 h, with a cyclohexanone selectivity of 95.3 %. The turnover frequency (TOF) of NaOH-Pd/WO 3 is approximately 3.5 times higher than that of the Pd/WO 3 . Detailed catalyst characterization and theoretical calculations reveal that the high activity and selectivity of NaOH-Pd/WO 3 for phenol hydrogenation to cyclohexanone are highly correlated with the concentration of oxygen vacancies in the catalyst. In-situ infrared and Raman analyses reveal that the OH - introduced by NaOH reacted with the lattice oxygen in WO 3 to abstract oxygen from the lattice, generating a significant number of oxygen vacancies. The possible reaction mechanisms for phenol hydrogenation were elucidated through combined density functional theory calculations and isotopic labeling experiments. This strategy of improving catalytic activity and selectivity by regulating the concentration of oxygen vacancies provides a theoretical basis for the design and optimization of industrial catalysts.
研究领域:
催化
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化学工程
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材料科学
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物理化学
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2015
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IF 4.529
Hangcheng Zhu,Yong Zhang,Xiaogang Yang,Hongyi Liu,Lan Shao,Xiumei Zhang,Juming Yao
The waste management of used flocculants is a thorny issue in the field of wastewater treatment . To natural cellulose based flocculants, utilization of hazardous cellulose solvent and simplification of synthetic procedure are the two urgent problems needing to be further improved. In this work, a series of natural dicarboxyl cellulose flocculants (DCCs) were one-step synthesized via Schiff-base route. The cellulose solvent (NaOH/Urea solution) was utilized during the synthesis process. The full-biodegradable flocculants avoid causing secondary pollution to environment. The chemical structure and solution property of the DCC products were characterized by FT-IR, 1 H NMR, 13 C NMR, TGA, FESEM , charge density and ζ-potential. Kaolin suspension and effluent from paper mill were selected to evaluate the flocculation activity of the DCCs. Their flocculation performance was compared with that of commercial cationic polyacrylamide and poly aluminium chloride flocculants. The positive results showed that the NaOH/Urea solvent effectively promoted the dialdehyde cellulose (DAC) conversion to DCC in the one-step synthesis reaction. The DCCs with the carboxylate content more than 1 mmol/g exhibited steady flocculation performance to kaolin suspension in the broad pH range from 4 to 10. Its flocculation capacity to the effluent from paper mill also showed excellent.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
FUEL PROCESSING TECHNOLOGY
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2016
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IF 3.847
Xinping Ouyang,Tao Ruan,Xueqing Qiu
Lignin was hydrothermal oxidation depolymerized by using H 2 O 2 as the oxidant and CuO/Fe 2 (SO 4 ) 3 /NaOH as catalysts. The effect of the solvents, including water, methanol, 1,4-dioxane, tetrahydrofuran , ethanol, and their co-solvent, on the depolymerization of lignin were investigated. It is found that the yield of monophenolic compounds reaches 17.92% by using 1:1 (v/v) of methanol/water as the reaction medium. The suitable proportion of methanol to water not only effectively maintains the alkalinity of the reaction medium and the solubility of lignin, but also suppresses the demethoxylation during the process of depolymerization reaction, resulting in an increase of contents of syringyl style monophenolic compounds which prevents the re-polymerization. Consequently, the yield of monophenolic compounds is increased.
研究领域:
化学工程
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有机化学
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可再生能源
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Mengjia Wu,Junhua Di,Lei Gong,Yu-Cai He,Cuiluan Ma,Yu Deng
Adipic acid is an important precursor for manufacturing Nylon-66, and various efficient renewable routes for adipic acid from lignocellulosic biomass are being explored. To effectively valorize biomass into adipic acid, a novel aqueous solution NaOH/ChCl:TH/water (6:24:160, wt/wt/wt) was firstly applied to pretreat sugarcane bagasse (SCB) at a room temperature (25 °C) for a short pretreatment time (1 min) for improving its saccharification efficiency. A deep eutectic solvent ChCl:TH was synthesized by mixing choline chloride (ChCl) and thiourea (TH). The cellulose structure changes of SCB were characterized by FTIR, XRD, SEM, TEM and LSCM. Composition analysis and reducing sugar yield were used to evaluate pretreatment efficiency. Hydrolysis for 72 h, the yields of reducing sugars and glucose from 40 g/L NaOH/ChCl:TH-SCB with complexed cellulases were obtained at 90.2 % and 94.1 %, respectively. Finally, the obtained SCB-hydrolysate was used for adipic acid production by E. coli MG1655 K12. Glucose in SCB-hydrolysate was consumed within 72 h, with a productivity of 0.39 g adipic acid/g glucose, accounting for 72.2 % of the theoretical yield. Further discovery, xylose in SCB-hydrolysate was also consumed for adipic acid fermentation, which contributed to an increase in adipic acid production. In view of transcriptome data, most of the genes involved in carbohydrate metabolism were most significantly up-regulated, which was conductive to improve the yield of adipic acid using biomass-hydrolysate as carbon source. Therefore, the NaOH/ChCl:TH-SCB hydrolysates were a better carbon source for adipic acid fermentation compared to commercial glucose. Obviously, this established rapid room temperature pretreatment with NaOH/ChCl:TH was proven to be effective for enhancing saccharification efficiency of SCB, and the hydrolysates had excellent adipic acid fermentability.
研究领域:
生物技术
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生物化学工程
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微生物学
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可持续化学
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产品关联
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
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2011
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IF 3.603
Panfeng Long,Aixin Song,Dong Wang,Renhao Dong,Jingcheng Hao
The formation of pH-sensitive vesicles and the rheological properties of the mixtures of perfluorolauric acid (PFLA) and its salts (PFL-Na and PFL-Li) neutralized via NaOH or LiOH were investigated in aqueous solution. When the right mixing ratios of the ionized to nonionzed PFLA molecules with a very high Krafft point are established, vesicles can spontaneously form at room temperature. The vesicles spontaneously formed in the PFLA/PFL-Na/H2O system with the rigid fluorocarbon chains were determined by atomic force microscopy images. Compared to those of hydrocarbon amphiphiles, these vesicle samples, which can be kept for 2 years at room temperature, are more stable. The phase transition from the vesicle phase to the lamellar lyotropic liquid crystal phase with the increase of pH was determined by freeze-fracture transmission electron microscopy images in the PFLA/PFL-Li/H2O system. The system of perfluoro fatty acid vesicles exhibits much more interesting rheological properties, compared to hydrocarbon fatty acid vesicles. The perfluoro fatty acid vesicle solutions display a much higher yield stress and viscoelastic properties, which depend on two factors: (i) the fluorinated alkyl chains of PFL–, which are in the crystalline state at room temperature because of their rigid chains compared to analogous hydrocarbon chains, and (ii) the packing of the vesicles, which is very dense. This is the first time that pH-sensitive vesicles exhibiting birefringence were constructed through ionizing perfluoro fatty acid, which may direct primarily toward acquiring an understanding of the mechanism of vesicles depending on the right mixing ratios of the ionized to the nonionzed perfluoro fatty acid molecules with a very high Krafft point and secondarily to expand the development of fluorinated surfactants in both fundamental research and practical applications.
研究领域:
胶体与界面科学
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软物质物理
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流变学
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超分子化学
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纳米材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）