JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2022
·
IF 4.598
Xuesong Shan,Keru Song,Siyu Huang,Jianwen Wang,Fengyue Shi,Dongyu Zhao
The annealing approach is usually used to synthesize carbon-based materials. We use polystyrene (PS) microspheres as a template to composite with carbon nanotubes (CNTs) loaded by Cu-Ni ions. After One-step high-temperature treatment, the PS microspheres disappear, and the composite materials become a three-dimensional porous structure. At the meantime, the Cu-Ni ions are reduced and attached to the material (CNTs/Cu-Ni/CP (CMP)). Then, the CMP material is coated with Polyaniline (PANI). The two-step high-temperature treatment accomplishes the Nitrogen-doped process of the material (CNTs/Cu-Ni/CP@CPANI (CMPN)). Electrochemical analysis indicates that materials have a high specific capacitance value (356F/g at 0.5 A/g). After 10,000 cycles of charging and discharging, the capacitance retention rate is 92.57 %. The assembled symmetrical supercapacitor possesses outstanding energy and power density (11.92 Wh kg −1 at 700.73 W kg −1 ).
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Applied Polymer Materials
·
2022
·
IF 4.855
Chengxin Yi,Changbo Xu,Ni Sun,Jian Xu,Meng Ma,Yanqin Shi,Huiwen He,Si Chen,Xu Wang
In this article, dimethyl methylphosphonate (DMMP) and methacrylamide (MAM) were used as flame retardants to develop an efficient synergistic flame-retardant system of phosphorus and nitrogen, and P(MMA-co-MAM)/DMMP products were prepared by free-radical polymerization, which had an excellent flame-retardant effect and high transparency. When only 14 wt % DMMP/MAM is added, the limiting oxygen index (LOI) value of poly(methyl methacrylate) (PMMA) can reach 23.1%, and the vertical combustion grade can attain V-0. The flame-retardant pathways of the DMMP/MAM flame retardant mainly include terminating a free-radical chain reaction and gas phase dilution, which indicates that the gas-phase flame retardant plays an important role in the PMMA flame retardant. Meanwhile, the optical properties of P(MMA-co-MAM)/DMMP products are almost the same as those of pure PMMA. In addition, when 14 wt % DMMP/MAM is added, the mechanical properties of P(MMA-co-MAM)/DMMP products are only slightly changed, and the Vicat softening temperature is 65 °C higher than the long-term service temperature of commercial PMMA, which can fulfill the needs of most markets. This research provides a valuable method for preparing transparent flame-retardant PMMA products.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2022
·
IF 11.357
Zheng Lian,Guojun Li,Shule Zhang,Weihua Ma,Qin Zhong
An innovative strategy to control nitrogen oxide emission from flue gas was developed using the wet flue gas denitrification technology. The use of cyclodextrin (CD) as an additive facilitated NO2 absorption by the sulfite absorbent. Compared with absorption by a sulfite solution (59.12%), the instantaneous absorption efficiencies employing CD improved to 94.57%. Moreover, 48 h of continuous absorption indicated cyclic utilization of CD. The favorable role of CD was ascribed to facilitating the limiting step for the entire NO2 absorption–dissolution process which included both water solubility and gas–liquid mass transfer. Furthermore, we propose a potential mechanism of CD/sulfite mixed solution absorbing NO2, among which the favorable role of the additive is related to its amphiphilic behavior toward gas and liquid phases. Additionally, a kinetic model describing the rates of gas–liquid transfer and macro absorption was established based on various operating conditions. This model explains the absorption improvement in the kinetic aspect and provides theoretical guidance for practical applications.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Water
·
2024
·Vol. 16
·期 19
·2821
·
IF 3
Wanying Xie,Ji Li,Tao Song,Yong Li,Zhenlin Wang,Xiaolei Zhang
To achieve the in situ capacity expansion of the post-denitrification biological aerated filter (BAF-DN), the integration of BAF with the anammox process (BAF/AX) was proposed. With the objective of maximizing retaining ammonia nitrogen, the operational optimization of BAF was achieved by two distinct strategies. The treatment performance of BAF demonstrated that the removal efficiencies of chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) was 66.3~67.3% and 4~12%, respectively, under conditions of low aeration intensity (0.4 m3·m−2·h−1) or a shortened empty bed residence time (EBRT) of 30 min. ResidualNH4+-Nin the BAF effluent served as the ammonia substrate for the subsequent anammox process, which was successfully launched by using ceramic particles and sponges as carriers. Notably, the sponge carrier facilitated a shorter start-up period of 41 to 44 days. Furthermore, the sponge-based anammox reactor exhibited a superiorNH4+-Nremoval capacity (≥85.7%), under operations of a shorter EBRT of 40 min, low influentNH4+-Nconcentrations (≤30 mg/L), and COD levels of ≤67 mg/L. In addition, a comprehensive evaluation of the BAF/AX process was conducted, which considered performance, cost-effectiveness, and engineering feasibility. The performance results illustrated that the effluent quality met the standard well (with a COD level of ≤ 50 mg/L, and a TN of ≤3.1~10.5 mg/L). Following a comparison against the low aeration intensity operation, it was recommended to operate BAF at a low EBRT within the BAF/AX process. Consequently, the treated volume was double the volume of the standalone BAF-DN, synchronously achieving low costs (0.413 yuan/m3).
研究领域:
环境工程
·
水处理技术
✓ 已验证
DOI
高影响因子
Nano Select
·
2021
·Vol. 3
·期 2
·402-410
·
IF 0
Yuelin Kong,Yu He,Yaping Wang,Gongwu Song
Herein, we first designed a one-step strategy to achieve matrix-free room temperature phosphorescence (RTP) materials by low temperature solid phase synthesis, using sodium citrate as carbon source and urea as nitrogen source. The NaF, NaCl, NaBr, and NaI were chosen as the inducer source of halogens to effective trigger the RTP emission from graphitic carbon nitride quantum dots (CNQDs) denoted F-CNQDs, Cl-CNQDs, Br-CNQDs and I-CNQDs. All the doped-CNQDs emitted bright fluorescence upon 365 nm irradiation. After the 365 nm UV lamp is off, only the Br-CNQDs showed green phosphorescence which can be observed by naked eye. The phosphorescence emission of Br-CNQDs is excitation-dependent from 510 to 610 nm with the average RTP lifetime of 70 milliseconds, which indicated Br-CNQDs could exhibit color-tunable phosphorescence. When 365 nm UV is off, Br-CNQDs emitted green afterglow for about 3 seconds observed naked eye, while the Br-CNQDs presented visible yellow afterglow for about 3 seconds with ceasing off 395 nm irradiation. The absolute phosphorescence quantum yield (PQY) of the Br-CNQDs powder reaches up to 3.64%. Thus, the color change and long lifetime of phosphorescence from the excitation-dependent feature could provide a security application for counterfeiting and information protection systems.
研究领域:
材料科学
·
光学
·
化学合成
✓ 已验证
DOI
Journal of Applied Spectroscopy
·
2025
·
IF 1
Wu H.,Meng L.
Nitrogen-doped carbon quantum dots (N-CQDs) were prepared by a one-step hydrothermal method using urea, aniline, and ethylenediamine as raw materials and nitrogen sources which exhibited good fluorescence performance. Spectral characteristics of the samples were analyzed using UV spectrophotometry, fluorescence spectrophotometry, and Fourier transform infrared spectroscopy. Optimal conditions, such as pH, reaction time, and ion concentration were investigated for N-CQDs. Under the optimal conditions (40 μL N-CQDs, buffer solution at pH 6 with a reaction time of 30 min), it was observed that cobalt ions caused a significant fluorescence quenching effect on the prepared N-CQDs, as determined by fluorescence spectrophotometry. The spiked recovery rates ranged from 95.8 to 104.6%, indicating that the N-CQDs could serve as a fluorescent probe for detecting the content of Co(II) in the actual environment. This method could be applied to the monitoring of heavy metal pollution in mine groundwater, the detection results of Co(II) using this method were very similar to ICP-MS, indicating that this method had good application prospects.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Coatings Technology and Research
·
2023
·Vol. 20
·期 5
·1513-1527
·
IF 2.3
Yao Hongrui,Bi Wenya,Yin Xu,Mu Shenglong,Sha Shiqiang,Wang Na
In this work, h-BN@STPP was successfully obtained by facile co-modification of sodium tripolyphosphate (STPP) and silane coupling agent (KH-550) on h-BN nanosheets, with waterborne epoxy coatings incorporated for metallic substrate corrosion protection. Results showed that the impedance modulus at the lowest frequency ( Z f = 0.1 Hz ) of h-BN@STPP composite coating increased three orders of magnitude in comparison with neat waterborne epoxy coating, exhibiting outstanding corrosion resistance. The reinforced anticorrosion performances of h-BN@STPP composite coatings could be attributed to the “labyrinth effect” of h-BN and passivation effect of STPP on the metal substrates. Graphical abstract
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
DOI
高影响因子
JOURNAL OF FLUORESCENCE
·
2023
·
IF 2.7
Zhao Xiaoyu,Du Qian,Qiu Huiying,Zhao Yaqin,Wang Songbai,Li Junfen,Dong Chuan
In this work, bright yellow fluorescent and multifunctional carbon dots (N-CDs) were prepared by hydrothermal method from O-phenylenediamine and 4-aminobenzoic acid. The fluorescence characterization showed that the N-CDs possessed good optical properties (QY = 32%) and excitation dependent multi-color emission. By exciting with 390 nm, the strong selective interaction of VB 12 with N-CDs could result in a sharp decrease in the luminescence of N-CDs at 567 nm. An efficient fluorescence sensor in aqueous solution was constructed which could linearly respond VB 12 in wide concentration ranges of 0–90 μM and 140–250 μM. The linear correlation coefficients of N-CDs and VB 12 were 0.9950 and 0.9968, respectively, and the detection limit was 0.119 μM. N-CDs were performed for sensitive determination of VB 12 in real samples. Moreover, the N-CDs were exploited to image cell. This N-CDs was a sensitive fluorescence probe to monitor VB 12 and presented prospective potential in living cells imaging. Graphical abstract Schematic diagram of the synthesis process and application research of N-CDs
研究领域:
生物化学
·
分析化学
·
生物医学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2023
·Vol. 52
·期 9
·5946-5954
·
IF 2.1
Lu Yuting,Bian Zhenglan,Chu Fenghong,Lu Jianwei,Hou Guoqiang,Hou Shili
In this paper, a hydrothermal strategy is reported for the synthesis of nitrogen-doped carbon dots (NCD) which used citric acid (CA) and urea as reactants with different pristine molar ratios of carbon/nitrogen atoms (C/N). The fluorescence emission wavelength of the aqueous solutions of NCD can be tuned from 462 to 546 nm under a single and uniform UV light excitation (365 nm). Through many characterization analysis methods, it is demonstrated that graphitic N and C=O extended the effective conjugation length which reduced the energy gap between the highest occupied molecular orbital (HUMO) and the lowest unoccupied molecular orbital (LUMO). This is considered to be responsible for the redshift and tunability of the fluorescence emission of NCDs with different C/N molar ratios. This will be useful for designing a synthetic strategy of long-wavelength fluorescence emission carbon dots (CDs) in a non-benzene ring precursor system. As a potential fluorescence sensor, the as-prepared NCDs can specifically detect Fe 3+ ions and Al 3+ ions in aqueous solutions. Additionally, the NCDs not only are nontoxic but also exhibit large and stable fluorescence intensity, indicating that they have broad potential application in the fields of sensors and optoelectronic devices.
研究领域:
材料科学
·
分析化学
·
生物传感
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 8
·1-16
·
IF 2.8
Liu Hui,Dai Jianfeng,Huang Danqiang,Yu Rui
The mitigation of electromagnetic wave pollution is a pressing concern that can be addressed by the effective utilization of microwave-absorbing materials characterized by low density, thin thickness, wide absorption bandwidth, and robust absorption strength. This work used a two-step solvent-thermal and hydrothermal approach to create nitrogen-doped reduced graphene oxide (NRGO)/ZnFe 2 O 4 hollow-structured composite microwave absorbent materials. The study of its microstructure reveals that the flaky NRGO is well adhered to the hollow ZnFe 2 O 4 with a rough surface. The findings indicate that the electromagnetic wave absorption characteristics of NRGO/ZnFe 2 O 4 are influenced by the variable contents of NRGO. At the NRGO doping level of 15%, the NRGO/ZnFe 2 O 4 composites exhibit the best electromagnetic wave absorption capabilities. With the matching thickness of 4.91 mm, the minimum reflection loss ( RL min ) can approach − 59.95 dB. This study serves as a significant point of reference for the development of highly effective electromagnetic wave absorption materials using graphene.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 5
·1-9
·
IF 5.479
Walekar Laxman S.,Zheng Mingda,Zheng Longhui,Long Mingce
Highly fluorescent carbon quantum dots co-doped with selenium and nitrogen (SeN-CQDs) were fabricated via a one-pot hydrothermal route using selenomethionine as the sole precursor. The SeN-CQDs aggregates have sizes between 30 and 45 nm and display blue fluorescence with a quantum yield of 8% at excitation/emission wavelengths of 350/445 nm. The fluorescence is pH dependent and decreases under acidic conditions. The doping of the CQDs with selenium and nitrogen was proven by X-ray photoelectron spectroscopy (XPS). Fluorescence is selectively quenched by perfluorooctanoic acid (PFOA), and this is accompanied by a decreased fluorescence lifetime. Quenching is not due to aggregation in view of the unaltered sizes of nanoparticles as revealed by TEM and DLS analyses. UV-vis absorption titration suggested the formation of an excited state complex between SeN-CQDs and PFOA, and quenching originates from the internal electron transfer in the excited state complex. The method was used to detect PFOA quantitatively in the linear range of 10–70 μM with a 1.8 μM detection limit. The nanoprobe has a high selectivity for PFOA over potentially interfering molecules. The practicability of the method was ascertained by accurate detection of PFOA in real samples by the standard addition method. The method may be further improved by tuning the interaction between PFOA and SeN-CQDs through optimizing the doping and the surface composition of the SeN-CQDs.
Schematic presentation of a fluorometric method for perfluorooctanoic acid detection by using a selenium and nitrogen co-doped carbon quantum dots as the fluorescent probe.
研究领域:
分析化学
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SYNTHESIS-STUTTGART
·
2024
·
IF 2.2
Taijie Guo,Wei Wang,Long Xu,Jiajia Dong
Here we report the utilization of NH-sulfamoyl fluorides (RNHSO2F) as reliable SuFEx synthons for the construction of various sulfamate esters. By using potassium fluoride as base, we are able to convert RNHSO2F to azasulfene intermediates under mild conditions and guarantee their further efficent ligation with phenols and alcohols.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）