JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 11
·49992
·
IF 2.52
Xiaoying Wang,Lili Wang,Bingyan Sun,Xiaomeng Chu,Xuteng Xing,Shaojie Liu,Erjun Tang
In this work, the sulfonated polystyrene brushes were grafted onto magnetic nanoparticles to obtain recoverable catalysts for efficient synthesis of ethyl N-phenylformimidate. First, the surface modification of Fe 3 O 4 with a particle size of about 10 nm was performed with the silane coupling agent of vinyl triethoxysilane (SG-151) to obtain Fe 3 O 4 with carbon–carbon double bonds on the surface (SG-Fe 3 O 4 ). Subsequently, SG-Fe 3 O 4 , styrene (St) and chloromethyl styrene (CMSt) were polymerized to obtain the magnetic chloromethylated polystyrene sphere (SG-Fe 3 O 4 @PS-Cl) with core-shell structure by solution copolymerization. Using St as monomer and SG-Fe 3 O 4 @PS-Cl as macromolecular initiator, the magnetic polystyrene brush of SG-Fe 3 O 4 @PS-PSt was obtained by activated regenerated electron transfer catalyst atom transfer radical polymerization. Finally, SG-Fe 3 O 4 @PS-PSt was sulfonated with sulfuric acid to form a magnetic sulfonated polystyrene brush of SG-Fe 3 O 4 @PS-PSH. SG-Fe 3 O 4 @PS-PSH was used as a recoverable acid catalyst to synthesize ethyl N-phenylformimidate. Due to the high loading of the sulfonic acid group of this catalyst, its added amount was lower than other solid acids such as p-toluenesulfonic acid. The results showed that the catalytic performance of SG-Fe 3 O 4 @PS-PSH was better than p-toluenesulfonic acid and commercial macroporous sulfonic acid resin. The external magnetic field can directly recover SG-Fe 3 O 4 @PS-PSH, simplifying the recovery of catalyst and reducing the catalyst loss. After recycling, the yield of ethyl N-phenylformimidate was not significantly decreased.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Xiang Shen,Tiande Xie,Jiangang Wang,Fan Wang
In this work, poly(N-acryloylmorpholine)-grafted ZrO 2 nanoparticles (ZrO 2 -g-PACMO) were directly blended with poly(vinyl chloride) (PVC) to prepare a hybrid membrane via the phase inversion method. In addition, the effects of ZrO 2 -g-PACMO and ZrO 2 nanoparticles on the structure and performance of resultant PVC membranes were comparatively investigated. The results indicated that the PVC/ZrO 2 -g-PACMO membrane exhibited a large macroviod of cross-section and a rough membrane surface. During membrane formation, the hydrophilic PACMO chains were preferably enriched onto the membrane surface, leading to the enhancement of surface hydrophilicity and the reduction of adhesion force between protein and membrane surface. The amount of adsorbed bovine serum albumin (BSA) on the poly(vinylidene fluoride)/ZrO 2 -g-PACMO decreases about 73% and 48% respectively, compared with original PVC and PVC/ZrO 2 membranes. Cycle filtration of pure water and BSA solution (0.5 g/L) confirmed that the total and irreversible membrane fouling were remarkably suppressed after incorporating ZrO 2 -g-PACMO into PVC membrane. Although the original ZrO 2 nanoparticle was also found to improve the protein fouling resistance of PVC membrane, there was a fatal limitation that the original ZrO 2 exhibited an agglomeration tendency during the membrane formation. The outcomes of the present work demonstrate that the synthesized ZrO 2 -g-PACMO nanoparticles have the potential for the design and preparation of anti-fouling PVC membrane.
研究领域:
材料科学
·
膜技术
·
化学工程
✓ 已验证
DOI
高影响因子
SYNLETT
·
2018
·Vol. 29
·期 09
·1244-1248
·
IF 2.369
Xiangwen Kong,Lihua Liu,Siqin Luo,Shilu Fan,Haisheng Qian,Hua Xiao
A triphenylphosphine-promoted [3+2] cycloaddition of α,γ-bis-substituted allenoates and N-tosylaldimines followed by alkene isomerization was disclosed, affording a series of functionalized 2-pyrroline derivatives in moderate chemical yields with random diastereoselectivities.
研究领域:
有机化学
·
药物化学
·
合成方法学
·
杂环化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2022
·
IF 12.92
Kaiyi Su,Chaofeng Zhang,Yehong Wang,Jian Zhang,Qiang Guo,Zhuyan Gao,Feng Wang
ABSTRACT Although different NbO x units are present in Nb 2 O 5 -based catalysts, the correlations between these structures and activity remain unclear, which considerably hinders the further development of Nb 2 O 5 photocatalysis . Herein, we utilized N- hydroxyphthalimide (NHPI) as the probe molecule to distinguish the role of different NbO x units in the activation of C–H bond under visible light irradiation. With the addition of NHPI, Nb 2 O 5 catalysts with highly disordered NbO 6 units exhibited higher activities than that with slightly disordered NbO 6 units (419–495 vs . 82 μmol·g −1 ·h −1 ) in photocatalytic selective oxidation of ethylbenzene . Revealed by Raman spectra, electron paramagnetic resonance spectra, and transmission-electron-microscopy images, highly disordered NbO 6 units were confirmed to act as the active sites for the transfer of photogenerated electrons from NHPI, promoting the generation of phthalimide- N -oxyl (PINO) radicals for the enhanced conversion of ethylbenzene under visible light irradiation. This study provides guidance on the role of local NbO x units in Nb 2 O 5 photocatalysis.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
ACS Omega
·
2019
·
IF 2.584
Lili Geng,Jianjun Gong,Guilong Qiao,Songshou Ye,Jinbao Zheng,Nuowei Zhang,Binghui Chen
Pt(NH3)4(NO3)2, Pt(NH3)4(Ac)2, (NH4)2PtCl4, and H2PtCl6 were used to prepare Pt/SAPO-11 catalysts to investigate the effect of Pt precursors on the hydroisomerization of n-dodecane. The catalyst derived from Pt(NH3)4(NO3)2 displays the best hydroisomerization activity and selectivity among these precursors. The hydroisomerization conversion of n-dodecane is affected by the platinum particle size, platinum dispersion, the location of platinum, and the valence state of platinum. The selectivity of n-dodecane is determined by the number of Brønsted acid sites and Pt crystal planes. These conclusions are verified by combining transmission electron microscopy, high-resolution transmission electron microscopy, hydrogen temperature programmed reduction, NH3-temperature programmed desorption, and Py-IR studies. The catalyst prepared with Pt(NH3)4(NO3)2 as the precursor exhibits the smallest platinum particle size and the highest platinum dispersion. Most of the platinum particles are supported on the external surface of SAPO-11 with the Pt(111) crystal face. Such a catalyst also possesses a suitable number of Brønsted acid sites and then displays the best catalytic performance. Obviously, the use of various precursors for the Pt-based catalyst can significantly affect the performance of Pt/SAPO-11 for the hydroisomerization of n-dodecane.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Yu Cheng,Haoran Guo,Pengfei Yuan,Xinpan Li,Lirong Zheng,Rui Song
To satisfy the practical requirements of electrochemical water splitting, developing a flexible, effective and sustainable approach for scalable production of bifunctional electrocatalyst for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is a tremendous issue to be rationally addressed. Herein, a solid-state diffusion strategy with Ni foam and N-doped carbon layers is applied to prepare multi-interfacial, self-supported and N-doped carbon nanotube (NCNT) encapsulated Ni nanoparticles (NPs) array bifunctional electrocatalyst (NCNT-NP@NF). Prominently, this NCNT-NP@NF is scalable to meet the application requirements and can be used as a binder-free electrode for direct the water splitting. The optimal sample demonstrate outstanding HER/OER performance in 1.0 M KOH, with low overpotential ( η 10 ) at 10 mA cm −2 during HER (96.1 mV) and OER (240 mV) process, which is extremely superior to the most reported metal-based electrocatalysts and even better than commercial IrO 2 (400 mV at 10 mA cm −2 for OER). Strikingly, when these bifunctional electrocatalysts are employed in a dual-electrode electrolyzer for water splitting, the NCNT-NP@NF only needs cell voltage of 1.54 V to drive overall water splitting in 1.0 M KOH, and displays excellent long-term stability (150 h for water splitting). Moreover, experiments combined with density functional theory (DFT) calculations clarify that the remarkable electrochemical activity and stability are mainly attribute to the synergistic effect of the uniform distribution of Ni NPs, heteroatomic doping, as well as district confinement effect of NCNT leading to enhanced electronic multi-interfacial transmission, all these factors co-accelerate electrocatalytic kinetics. Accordingly, this solid-state diffusion method possesses a favorable potential to construct a multi-interfacial and self-supported electrocatalysts in the fields of sustainable supply of clean energies.
研究领域:
电化学
·
材料科学
·
催化
·
能源材料
·
可持续能源
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2017
·Vol. 10
·期 4
·796-803
·
IF 4.803
Shi Feng,Xingyue Li,Jia Huo,Qiling Li,Chao Xie,Tingting Liu,Zhigang Liu,Zhenjun Wu,Shuangyin Wang
Graphical Porous carbon electrode : CoS 2 @N/S-codoped porous carbon is prepared through an electrodeposition–ZIF conversion–sulfuration strategy. The loading of active sites can be controlled easily by varying the electrodeposition time. The resulting material can be employed directly as a working electrode for the hydrogen evolution reaction and shows an excellent catalytic activity and stability. A convenient, controllable method to fabricate an electrode is necessary to achieve the practical application of a hydrogen evolution reaction (HER) catalyst. In this work, an electrodeposition–ZIF conversion–sulfuration strategy is developed to produce a CoS 2 @N/S-codoped porous carbon (CoS 2 @NSC/CFP) to drive the HER efficiently. CoS 2 @NSC/CFP was prepared by the electrodeposition of Co(OH) 2 on a carbon fiber paper followed by conversion into ZIF-67 and subsequent sulfuration with sulfur. The loading of electroactive components can be controlled easily in the range of 0.7–10.0 mg cm −2 by varying electrodeposition time from 5 min to 2 h. The resulting material can be employed directly as a working electrode for the HER and it shows an excellent catalytic activity and stability with an overpotential of 95 mV at 10 mA cm −2 and 158 mV to reach 100 mA cm −2 in an acidic medium. The high efficiency is related intimately to the high dispersion of ultra-small CoS 2 nanoparticles, heteroatom-codoping, and the 3 D porous network configuration of the carbon fiber paper.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Industrial Chemistry & Materials
·
2024
·
IF 0
Jiayao Cui,Junyong Min,Hao Wang,Jianglan Shui,Lishan Peng,Zhenye Kang,Jieyuan Liu,Qingjun Chen,Shuo Bai,Yanrong Liu
Developing single-atom Fe–N4/C catalysts is crucial for the large-scale implementation of proton exchange membrane fuel cells (PEMFCs). While Fe–N4/C catalysts are inherently active in accelerating the slow ORR process, their performance is still inferior to that of Pt/C. Herein, a trace Co-doped Fe single-atom catalyst (Fe(tCo)–N–C) containing more active Fe2N8 sites has been synthesized. Interestingly, compared with typical FeN4 sites in an Fe–N–C electrocatalyst, the Fe2N8 sites generate a larger Fe–N bond length due to Co-doping. The elongated Fe–N bond in Fe2N8 lowers the d-band center and charge density of iron sites, enhancing the ORR process by facilitating the formation of *OOH and generation and desorption of *OH. Fe(tCo)–N–C manifested excellent acidic and alkaline ORR activity, with a half-wave potential (E1/2) of 0.80 V in HClO4 solution and 0.89 V in KOH medium. More importantly, high peak power densities (Pmax) were realized by applying Fe(tCo)–N–C in PEMFCs, with the Pmax reaching 890 mW cm−2 in H2–O2 and 380 mW cm−2 in H2–air. Additionally, trace Co dopants in the catalyst improved carbon graphitization and provided high ORR catalytic stability. This research introduces an innovative approach to engineering highly active Fe2N8 sites, providing valuable insights for the sustainable progress of PEMFC technology.
研究领域:
电化学
·
催化
·
能源材料
·
燃料电池
·
纳米技术
✓ 已验证
DOI
LANGMUIR
·
2021
·
IF 3.882
Aling Chen,Qingfeng Yi,Kuang Sheng,Yuebing Wang,Jiangchuan Chen,Qiaoli Zhang,Kaiwen Xiang,Guanghua Tan
Development of high-efficiency oxygen reduction reaction (ORR) catalysts under neutral conditions has made little research progress. In this work, we synthesized a three-dimensional porous N/P codoped carbon nanosheet composites (CNP@PNS) by high-temperature thermal treatment of dicyandiamide, starch, and triphenylphosphine and subsequent porous structure-making treatment using the NaCl molten salt template. In the neutral solution, the electrocatalytic performance of the CNP@PNS-4 catalyst exhibits an onset potential of 0.98 V (vs reversible hydrogen electrode) and a half-wave potential of 0.91 V for ORR, which greatly surpasses commercial Pt/C (40%). Three kinds of neutral metal–air batteries (Zn–air, Al–air, and Fe–air) using the prepared samples as cathodic catalysts were constructed, corresponding to the maximum power density of 120.2, 78.3, and 18.9 mW·cm–2, respectively. Also, they reveal outstanding discharge stability under different current densities. The density functional theory calculation depicts the reduction of the free energy of the determining step and subsequent decline of the overpotential for ORR.
研究领域:
材料科学
·
电化学
·
能源科学
✓ 已验证
DOI
高影响因子
Environmental Science-Nano
·
2020
·Vol. 7
·期 12
·3814-3823
·
IF 7.683
Hanfeng Zhou,Zhibo Deng,Tianbao Liu,Tao Liu,Lijuan Zhang,Xintai Su,Zhang Lin
The science linking thermochemical conversion of large-scale industry oily sludge with applied materials has been improved in the last ten years. However, with the traditional converting methods it is hard to precisely control the composition and structure of oily sludge-based products during pyrolysis due to the complexity of the composition of the oily sludge. Here, a chlorinating calcination method using sodium chloride (NaCl) as a chlorinating salt and template was first developed to prepare porous Fe–N–C materials (FCN-500) through pyrolysis of oily sludge containing iron-bearing minerals and pyridine. The formation mechanism of FCN-500 was proposed, where iron ions (Fe3+) from the inorganic component (anorthite) in the sludge were rapidly dissociated with the assistance of NaCl, followed by coordination with the organic component (pyridine nitrogen) in the oily sludge to form the pyridine nitrogen–iron ((C5H6N)n–Fe) complex, and then carbonization. As-obtained FCN-500 exhibited higher specific capacitance (286.3 F g−1 at a current density of 0.5 A g−1), enhanced energy density (33.5 W h kg−1 at a power density of 606.1 W kg−1) and more excellent stability and durability (more than 80.1% capacitance retention after 10 000 cycles) compared with two other electrodes. The reasonably better performance of the obtained FCN-500 in supercapacitors (SCs) is attributed to its large surface area, hierarchically porous channels, high conductivity, and unique Fe–N–C structure. Therefore, this work not only provides a feasible way to solve the bottleneck problem in sludge pyrolysis, but also provides a method to design large scale porous Fe–N–C materials for practical applications.
研究领域:
环境科学
·
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Chun Bai,Kexin Li,Yanping Wang,Haining Liu,Huifang Zhang,Quan Li,Jun Li,Xiushen Ye,Zhijian Wu
ABSTRACT A novel boron flotation agent (N-2-hydroxyoctadecyl-N-Methylglucamine, NHO-NMDG) was fabricated using 1,2-epoxyoctadecane and N-methyl-D-glucamine. The obtained collector possesses both collecting and foaming properties and it was characterized by nuclear magnetic resonance, mass spectrometry, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy methods. The flotation performance for boron removal from the salt lake brine has been studied. The flotation experiments indicated a highly effective removal of boron from the salt lake brine. The boron removal rate in the Da Qaidam brine could reach 67.08% by NHO-NMDG. The mechanism analysis shows that the meglumine group in the bifunctional flotation agent can be complexed with boron, and the long-chain alkyl group can attach to the surface of the bubble and enter into the bubble layer, so as to separate boron from the aqueous solution.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Boyin Yan,Songxue Wang,Zhiquan Liu,Da Wang,Wenxin Shi,Fuyi Cui
In this work, the UV 254 /H 2 O 2 process was utilized to remove β-N-methylamino- l -alanine (BMAA), a kind of cyanobacteria neurotoxin, and the influence of reaction parameters and environmental factors on the degradation of BMAA has been systematically investigated. The results showed that BMAA could be effectively removed in the UV 254 /H 2 O 2 system compared to UV or H 2 O 2 alone and OH was confirmed as the main ROS to degrade BMAA. The degradation rate of BMAA increased first and then decreased with the increase of pH and the maximum k obs was 0.1545 min −1 obtained at pH 9. The removal of BMAA in the UV 254 /H 2 O 2 system was inhibited in actual water, while the degradation rate of BMAA in actual water could still exceed 90% by appropriately extending the reaction time. The decrease in the degradation efficiency of BMAA in actual water was primarily due to the ultraviolet light absorption and competition effects of NOM, and anions (Cl − and HCO 3 − ) would also inhibit the degradation of BMAA. Five by-products ([M − H] - = 118, 103, 88, 87 and 59) were identified in this study and the degradation pathways of BMAA were proposed. The production of by-products was attributed to the fracture of the C–N bond and hydroxylation reaction. This study is worthwhile to deepen the understanding of the degradation mechanism of BMAA in the UV 254 /H 2 O 2 system.
研究领域:
环境科学
·
毒理学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）