Journal of Energy Storage
·
2025
·
IF 9.8
Shidong Song,Junjie Ma,Huanlei Zhao,Phumlani F. Msomi,Jiahao Ren,Yanan Liu,Run Ma,Wanyu Ye
In terms of stability and safety, quasi-solid-state lithium-oxygen batteries (QSSLOBs) outperform traditional liquid LOBs. However, using redox mediators (RMs) in QSSLOBs requires unique strategy to inhibit the shuttle effect of RMs. In this work, a PEO-based oxygen electrode with anchored 4-OH-TEMPO (4-hydroxy-2,2,6,6-tetramethyl-piperidinyloxy) RM (referred to as TEMPO-PEO) is developed via hydrogen-bonding interaction for QSSLOBs. The TEMPO-PEO oxygen electrode can perform both significant mediation function and oxygen reduction reaction (ORR) activity. The QSSLOB using TEMPO-PEO electrode achieves a low discharge/charge voltage gap of 0.9 V and a high Coulombic efficiency of 96.8 %, which is significantly superior to the counterparts using TEMPO solution (TEMPO cell) or unanchored TEMPO (TEMPO+PEO cell). On this basis, the TEMPO-PEO cell achieves an unprecedented cycle performance for 320 cycles under the limited capacity of 300 mAh g −1 , overwhelmingly outperforming the counterpart cells that only deliver 63 cycles (TEMPO cell) and 119 cycles (TEMPO+PEO cell), respectively. After cycling, the TEMPO RM can still be well retained on TEMPO-PEO oxygen electrode and no significant side product is formed on the after-cycled Li anode of TEMPO-PEO cell, explicitly demonstrating a strong and consistent anchoring effect on suppressing the shuttling of RM species.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2024
·
IF 5.6
Haidong Li,Guangyue Zhao,Yuxin Yang,Danli Zhong,Zhenxing Yang,Chengyin Wang
In this work, a series of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) radicals bearing different functional groups were exploited as a simple catalyst to promote electrochemiluminescence (ECL) generation in luminol/H 2 O 2 system. These TEMPO radicals were found to facilitate the electrochemical oxidation of H 2 O 2 and luminol through different catalytic mechanisms, as well as the subsequent ECL generation of luminol/H 2 O 2 system. The electrochemical oxidation and luminol ECL generation could be tuned by the functional group on the para -position of TEMPO, for which the structure/activity relationship was revealed. Finally, with the combination of enzymatic system, luminol ECL enhancement up to 9.6-fold was obtained through the catalysis of 4-hydroxyl-TEMPO. The enhanced luminol ECL allows acquiring brighter ECL images in a single-electrochemical system (SEES) for multiplex detection of cholesterol, H 2 O 2 and glucose.
研究领域:
分析化学
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电化学
·
生物分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2013
·
IF 3.473
Jianli Wang,Miao Zhang,Zhi Zheng,Fengwen Yu,Jianbing Ji
The effectiveness of indirect oxidation of glycerol to prepare 1,3-dihydroxyacetone (DHA) was further verified in this work. The oxidation of the 1,3-acetalized glycerol (5-hydroxyl-2-phenyl-1,3-dioxane, HPD) to 1,3-acetalized dihydroxyacetone (2-phenyl-1,3-dioxan-5-one, PDO) was successfully achieved by Montanari oxidation system (NaClO/NaBr/Magnetic recyclable TEMPO). The magnetic polystyrene nanosphere immobilized TEMPO catalyst (1.02 mmol g −1 nitroxyl radical) was readily prepared and characterized by elemental analysis, particle size analysis, and TEM. The catalyst can be used as recyclable and efficient catalyst for HPD oxidation, and high catalytic activity for up to five cycles was obtained. The target product DHA can be efficiently separated by biphasic extraction without complicated purification. The overall yield of DHA was 95.3%, and 78.1% yield with >99% purity after crystallization.
研究领域:
化学工程
·
催化化学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
FIBERS AND POLYMERS
·
2024
·Vol. 25
·期 11
·4271-4281
·
IF 2.2
Hou Mohan,Wang Lifang,Xu Qiuyu,Zhang Xuepeng,Yang Xue,Zhang Lei,Bai Yun,Li Yanyun,Liu Lifang
Waste cotton fibers are an ideal raw material for extracting nanocellulose crystals (CNCs), benefitting from their high cellulose content. In this study, the waste cotton fibers from the calendering finishing process were used to extract CNCs by sulfuric acid, TEMPO oxidation, and phosphoric acid methods, aiming to create a new way to reutilize the waste cotton fiber and also to verify the practicability that the phosphoric acid method can replace sulfuric acid and TEMPO oxidation methods. The CNCs obtained from the three methods are all in cellulose I state with an average length of 200-500nm and diameter of 15-20nm, indicating that the waste cotton fiber can extract CNCs. However, the CNCs from the phosphoric acid method showed the highest thermostability but the lowest crystallinity, while the ones from the sulfuric acid and TEMPO oxidation methods had higher crystallinity but lower thermal stability. Overall, the three methods are all acceptable for preparing CNCs, but the phosphoric acid method has more significant potential due to its low cost, environmental friendliness, and safety. Graphical abstract
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 28
·20199-20209
·
IF 3.9
Yaping She,Xinyu Chen,Mengya Wang,Anqiu Liu,Xiaochen Wang,Daming Gao,Kunhong Hu,Miao Hu
Heterogeneous solvent-metal-free aerobic oxidation of alcohols under ambient conditions is interesting but remains a significant challenge. Herein, a series of porous TEMPO-functionalized poly(ionic liquid)s (TEMPO-PILs) featuring a pure polycationic framework were successfully developed through the free radical polymerization of the ionic liquid 3-(2-chloroacetic acid-2,2,6,6-tetramethyl-1-oxo-4-piperidyl)-1-vinylimidazolium chloride and bis-vinylimidazolium bromide salt. Characterizations revealed that the obtained TEMPO-PILs possessed a high TEMPO density, abundant bromide ions, and a tunable porous structure, which enabled them to serve as solvent-free heterogeneous organocatalysts for the metal-free aerobic oxidation of benzyl alcohol under ambient conditions, exhibiting high catalytic activity and stable recyclability. A high yield of 99% coupled with a turnover frequency (TOF) of 13.3 h−1 was obtainable, which is higher than most of the reported TEMPO-based heterogeneous catalysts, even superior to homogeneous TEMPO-functionalized ionic liquids. Furthermore, a broad range of alcohols were effectively converted into their corresponding ketones and aldehydes. A possible reaction mechanism is proposed for understanding the catalytic oxidation behavior, indicative of the synergistic effect of TEMPO moieties and bromide ions.
研究领域:
化学
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催化科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymer Chemistry
·
2015
·Vol. 6
·期 43
·7514-7523
·
IF 5.52
Yujie Liu,Xuepu Wang,Wenguang Song,Guowei Wang
A series of novel silica nanoparticles functionalized with multiple TEMPO groups were synthesized using a novel, efficient and versatile protocol. First, the amino-functionalized silica nanoparticles (SN-NH2) were obtained using an improved one-pot hydrolysis and co-condensation procedure of APTES and TEOS agents, and further modified with 2-bromoisobutyryl bromide for macro-initiator (SN-Br) by amidation reaction. Then, the polymer grafted silica nanoparticles (SN-g-PGMA) with a dense shell layer of PGMA side-chains were realized via the surface-initiated atom transfer radical polymerization (SI-ATRP) procedure in a controlled manner. Subsequently, the azido groups were introduced onto PGMA side-chains by the quantitative ring-opening reaction of an epoxide with a sodium azide agent, and the TEMPO groups were further attached by efficient “Click” chemistry with propargyl-TEMPO for the target SN-g-(PGMA-TEMPO). The evidence for the successful synthesis of target polymers and intermediates was sufficiently provided by FT-IR, EPR, XPS, TEM, 1H NMR, and TGA measurements. As an important task, the catalytic activity of the synthesized SN-g-(PGMA-TEMPO) was evaluated by the oxidation of benzylic alcohols according to the Anelli protocol, as well as the excellent efficiency, stability and recyclability of the catalyst were also confirmed.
研究领域:
材料科学
·
有机化学
·
催化化学
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2025
·
IF 12.5
Fang Tian,Wenyuchu Chen,Weiliang Guan,Yujin Li,Zan Ni,Chongsheng Zhang,Xiaona Wang,Luyun Cai
Surimi is widely appreciated for its preferred texture and nutritional profile. However, maintaining its superior gel-forming properties while preventing nutrient loss caused by the washing process remains challenging. In this study, pre-emulsions made from pea protein isolate (PPI), pterostilbene (PTE), TEMPO-oxidized cellulose (TOC), and coconut oil (CO) were used as a fat substitute to improve the gel properties of surimi. These were incorporated into brown croaker ( Miichthys miiuy ) surimi. The results showed that the PPI-CO-TOC-PTE pre-emulsion (P-C-T-P) had a small d 4,3 particle size (283.5 nm). Molecular docking simulations demonstrated that TOC enhanced hydrogen bonding interactions between PPI and PTE. Adding P-C-T-P significantly improved the gel strength (2002.33 ± 48.74 g × mm) and water-holding capacity (91.40 ± 0.37 %) of the surimi gels. Furthermore, the protein network structure was denser in the P-C-T-P group. The surimi with P-C-T-P showed higher storage and loss moduli and the highest levels of hydrogen bonding, hydrophobicity, and β-sheet content. Thus, P-C-T-P addition improved surimi gel properties compared with directly supplying lipids to surimi.
研究领域:
食品科学
·
营养学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2014
·
IF 4.086
Lihuan Xu,Fang Yang,Chang Su,Lvlv Ji,Cheng Zhang
Two 2,2,6,6-tetramethylpiperidinyl-N-oxy (TEMPO) contained polypyrrole (PPy) derivatives with the different side-chain length were synthesized by esterification of 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radial with pyrrole butyric acid and pyrrole caproic acid. Then the homopolymers of 4-(3-(Pyrrol-1-yl)butyryloxy)-2,2,6,6-tetramethylpiperidin-1-yloxy (PPy-B-TEMPO) and 4-(3-(Pyrrol-1-yl)hexanoyloxy)-2,2,6,6-tetramethylpiperidin-1-yloxy (PPy-C-TEMPO) were prepared by chemical oxidative polymerization. The structure, morphology, electrochemical properties of prepared polymers were characterized by fourier transform infrared spectroscopy (FTIR), ultraviolet visible spectroscopy (UV-vis), scanning electron microscopy (SEM), cyclic voltammograms (CV) and electrochemical impedance spectra (EIS), respectively. Also, the charge-discharge properties of the prepared polymers were studied by galvanostatic charge-discharge testing. The results demonstrated that the as-synthesized nitroxide radical polymers showed a reversible two-electron redox reaction process in the potential limits of 2.5–3.0 V and 3.4–3.8 V vs Li/Li + , respectively. Under our experimental conditions, PPy only presented the discharge capacity of 16.5 mAh·g −1 at 20 mA·g −1 between 2.5 and 4.2 V, while PPy-B-TEMPO with the short side-chain linked to TEMPO groups exhibited an initial discharge capacity of up to 86.5 mAh·g −1 with two well-defined plateaus. Furthermore, the PPy-C-TEMPO with the longer linking side-chain even displayed a discharge capacity of 115 mAh·g −1 . These superior electrochemical performances were ascribed to the flexible linking side-chain and the introduction of stable conductive PPy main chain, which benefits the improvement of charge carrier transportation in the aggregated polymer bulk.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 141
·期 2
·e54774
·
IF 3
Wenyu Zhang,Yu Zhang,Weijie Cai,Dazhi Wang,Shaoyin Zhang
2,2,6,6-Tetramethylpiperidinium-nitroxide (TEMPO) is a mild and efficient catalyst, which is important in the industrial production of selective oxidation of alcohols to the corresponding aldehyde or ketone compounds. However, it is a challenge to recover the expensive TEMPO catalyst in homogeneous catalytic systems. In this study, a novel polymer-supported catalyst was prepared using 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxy (4-OH-TEMPO) and polyaromatic ether sulfone (PAES). The successful grafting of 4-OH-TEMPO in PAES-C was demonstrated by 1 H nuclear magnetic resonance ( 1 H NMR) and Fourier transform infrared (FT-IR), load capacity can be calculated by elemental analysis (EA). BET and scanning electron microscopy (SEM) to depict the structure-performance relationship. Herein, SEM images revealed the existence of porous structure. This structure can effectively adsorb NO molecules to form a PAES-TEMPO/NO x catalytic system to selectively oxidize benzyl alcohol. The experimental results indicated the high activity, the subsequent benzyl alcohol oxidation cycle can reach more than 93% conversion without showing a large loss of selectivity. More importantly, the as-prepared catalyst exhibited the attractive recyclability (recovery rate is 98%). After 10 consecutive runs, no significant loss of conversion and selectivity was observed (the conversion rate of benzyl alcohol was more than 93% and the selectivity was more than 95%). This study might provide some recommendation on the development of highly efficient catalysts for alcohol oxidation.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
Nano Materials Science
·
2024
·
IF 12.6
Hua-Jie Wang,Hao Peng,Wen-Hao Ji,Jia-Xin Wang,Xiao-Yan Du,Wen Song,Wen Zhang,Fazli Wahid,Ali Raza
Face masks play a pivotal role in preventing infection transmission. However, the capture of infection-sourced particles in face masks poses challenges related to reuse, necessitating proper disposal. We developed a self-sterilizable polypropylene-based membrane for face masks to address challenges associated with infection transmission prevention. The membrane, created using 3D printing, underwent functionalization with zinc oxide (ZnO) and polydopamine (PDA)-TEMPO to achieve broad-spectrum light absorption and facilitate self-sterilization through photocatalytic and photothermal effects upon light exposure. The hydrophobic surface (water contact angle: 133 ± 2°) minimized moisture accumulation, and the membrane exhibited robust mechanical properties, including shear strength (1.25 ± 0.5 kPa) and peel resistance strength (112.8 ± 11.2 kPa). The evaluation demonstrated stability in airflow (0–500 cm 3 /s) and excellent aerosol filtration efficiency (94.8 ± 0.6 %) for particles (PM 0.3, PM 2.5, PM 10), comparable to commercial masks. The membrane showed antibacterial efficacy over five uses in a simulated respiratory environment. Safety assessments confirmed biocompatibility through cytocompatibility and skin irritation assays. In conclusion, this membrane offers efficient filtration and photo-triggered sterilization, presenting a promising solution for next-generation face masks to address concerns related to reuse, disposal, and infection control.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2017
·Vol. 11
·期 4
·554-563
·
IF 1.712
Wu Bozhen,Geng Biyao,Chen Yufei,Liu Hongzhi,Li Guangyao,Wu Qiang
Bleached bamboo kraft pulp was pretreated by 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO)- mediated oxidation using a TEMPO/NaBr/NaClO system at pH = 10 in water to facilitate mechanical disintegration into TEMPO-oxidized cellulose nanofibrils (TO-CNs). A series of TO-CNs with different carboxylate contents were obtained by varying amounts of added NaClO. An increase in carboxylate contents results in aqueous TO-CN dispersions with higher yield, zeta potential values, and optical transparency. When carboxylate groups are introduced, the DPv value of the TO-CNs remarkably decreases and then levels off. And the presence of hemicellulose in the pulp is favorable to TEMPO oxidization. After the oxidization, the native cellulose I crystalline structure and crystal size of bamboo pulp are almost maintained. TEM micrographs revealed that the degree of nanofibrillation is directly proportional to the carboxylate contents. With increasing carboxylate contents, the free-standing TO-CN films becomes more transparent and mechanically stronger. The oxygen permeability of PLA films drastically decreases from 355 for neat PLA to 8.4 mL∙m –2 ∙d –1 after coating a thin layer of TO-CN with a carboxylate content of 1.8 mmol∙g –1 . Therefore, inexpensive and abundant bamboo pulp would be a promising starting material to isolate cellulose nanfibrils for oxygen-barrier applications.
研究领域:
高分子材料
·
纳米纤维素
·
包装材料
·
生物基材料
·
阻隔性能
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2018
·
IF 3.235
Wenbin Zhang,Peng Chen,Shengyou Chen,Yuyang Wei
In order to emphasize the importance of electrolyte-tuning in the nitroxyl radicals mediated electrocatalytic reactions , methanol and glycine electrooxidation reactions catalyzed by TEMPO under different properties (pH, identity, concentration) of buffer solutions were investigated by cyclic voltammetry . It was discovered that in both carbonate buffer solutions and borate buffer solutions, catalytic abilities increase with the rising of pH for both glycine electrooxidation and methanol electrooxidation. The electrocatalytic performance is also affected by the identity of buffer, for both cases of glycine and methanol, the electrooxidation activities in borate buffer solutions are apparently higher than those in carbonate buffer solutions. For both glycine and methanol electrooxidation, relationships between concentrations of carbonate ions and relative catalytic current densities were observed to be volcano-shaped, while electrocatalytic abilities increase with the increasing of concentrations of borate ions within the studied concentration range. These findings suggest that the electrolyte should be treated as important as the catalyst in the designing of nitroxyl radicals mediated electrocatalytic systems.
研究领域:
电化学
·
催化
·
分析化学
✓ 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）