ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2019
·
IF 7.149
Zhiqiang Sun,Lei Zhao,Caihong Liu,Yufei Zhen,Jun Ma
A novel synergetic mechanism of hydroxyl radical (•OH) oxidation and an intra-electron-transfer nonradical reaction was found in the catalytic ozonation of ketoprofen (KTP) with the in situ N-doped hollow sphere carbon (NHC). Outperforming the conventional •OH-based catalytic ozonation process, O3/NHC not only realized an enhancement of the pseudo-first-order rate constant of 11 times in comparison with that of O3 alone, but was also endowed with a high stability over a wide pH (4–9) and temperature (15–35 °C) range for the degradation of KTP. The high graphitization degree (ID/IG = 0.78–0.88) and low unsaturated oxygen content (0.10–1.38%) of NHC highlighted the dominant role of N-heteroatoms in the O3/NHC system. The specific effects of different N species were confirmed by a relationship study (N property vs catalytic activity) and X-ray photoelectron spectroscopy characterization. The graphitic N forming in the bulk of the graphitic structure served as the “electron-mobility” region to promote KTP degradation with the transfer of electrons from the KTP molecule to O3 via a nonradical reaction process. The pyrrolic and pyridinic N located at defects of the graphitic structure acted as the “radical-generation” region to decompose O3 into •OH for degrading KTP by a radical oxidation process. This finding provided a brand new insight into engineering N-doped carbonaceous catalysts precisely in the catalytic ozonation process for the efficient treatment of organic-contaminated water.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
Polymers
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2022
·Vol. 14
·期 10
·1970
·
IF 4.967
Tong Chen,Hongwei Zhang,Sanping Zhao
To fabricate N-CQDs hybrid thermo-sensitive polymer (poly-N-CQDs), N-doped carbon quantum dots (N-CQDs) with strong blue fluorescence and poly(N-isopropylacrylamide-co-acrylic acid) (poly(NIPAAm-co-AAc)) copolymer with thermo-sensitivity were synthesized, respectively. Subsequently, the coupling reaction between. the -COOH groups of poly(NIPAAm-co-AAc) and the -NH2groups on the surface of the N-CQDs was carried out. The fluorescence spectra show that the coil-globule transition of the poly-N-CQDs coincided with intensity changes in the scattering peak at excitation wavelength with the temperature variations. The phase transition temperature and the fluorescent intensity of poly-N-CQDs can be regulated by modulating the composition and concentration of poly-N-CQDs as well as the temperature and pH of the local medium. The thermo-sensitivity and fluorescent properties of the poly-N-CQDs displayed good stability and reversibility. The fluorescence intensity and emission wavelengths of the poly-N-CQDs significantly changed in different solvents for solvent recognition. The poly-N-CQDs was employed as a fluorescent probe for Fe3+detection ranging from 0.025 to 1 mM with a limit of detection (LOD) of 9.49 μM. The hybrid polymer materials have the potential to develop an N-CQDs-based thermo-sensitive device or sensor.Keywords:N-doped carbon quantum dots;thermo-sensitive polymer;phase transition temperature;solvent recognition;ion detection
研究领域:
材料科学
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化学
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生物传感
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
·
IF 24.319
Yufei Zhen,Zhiqiang Sun,Hang Qie,Yixuan Zhang,Caihong Liu,Dongwei Lu,Wei Wang,Yu Tian,Jun Ma
Surface-dependent nonradical oxidation of N-doped carbon (NC)-based peroxymonosulfate (PMS) system features high stoichiometric efficiency and target degradation selectivity. However, these are severely limited by the ineffective mass transfer of organics and PMS to NC surface. Herein, we utilize membrane confinement to enhance the interaction between organics/PMS and NC catalyst, and propose the synergy mechanism of surface reaction and membrane confinement towards organics removal. The NC catalyst layer is firstly uniformly loaded throughout the ceramic membrane (NC@CM) via an innovative simultaneous polymerization-coating method. As expected, NC@CM/PMS system significantly expedites the surface reaction dominant oxidation in the filtration-through mode, and its kinetics constant for bisphenol A removal is 3700 times higher than that of NC powder/PMS system. Moreover, it has high selectivity in removal of targeted organics such as BPA (81–100 % removal rate) under various interferences (anions, NOM, water sources) due to the corporation of surface reaction and membrane sieving effect. Mechanism study reveals that the synergy of membrane confinement and surface reaction of NC@CM/PMS system removes large size disturbance and reinforces mass transfer process of reactive species towards target organics, and promotes the generation and transformation of reactive species on the NC surface. Our system can selectively and efficiently remove targeted micropollutants with strong anti-interference capability, which is of great significance in practical application.
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
SOLAR ENERGY
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2018
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IF 4.374
Lianjing Zhao,Leilei Zhao,Weinan Xue,Wenjuan Fang,Yuan Wang,Yan Li
To improve the catalytic activity of carbons in counter electrodes (CEs), Cu nanoparticles (NPs) were introduced into mesoporous N-doped carbons (N-C) derived from metal-organic frameworks (MOFs) to prepare the composites of N-C and Cu NPs (N-C@Cu) via impregnation and subsequent reduction method in this work. The obtained N-C@Cu composites with 2–4 nm Cu NPs uniformly distributing in N-C were deposited onto fluorine doped tin oxide (FTO) substrates by screen-printing to fabricate CEs in quantum dot solar cells (QDSCs). The N-C@Cu CEs exhibit higher electrocatalytic activity than both pristine N-C/FTO and commonly used Cu 2 S/FTO CEs, which could be ascribed to the synergistic effect between Cu x S NPs with the excellent electrocatalytic ability and MOF derived N-C with high graphitization, large hydrophilic surface as well as the abundant dopant active sites on the reduction of polysulfide. The superior performance of N-C@Cu composites results in an improved fill factor and a high short circuit current density. Based on optimized N-C@Cu CEs and Zn-Cu-In-Se quantum dot sensitizers, the QDSCs obtained present a promising power conversion efficiency of 9.23%, significantly superior to those of pristine N-C/FTO (7.20%) and Cu 2 S/FTO (8.89%) CEs based QDSCs.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
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2025
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IF 5.4
Junjie Ma,Wei Li,Xiaoqi Lan,Zheng Liu,Fenghai Zhou,Mingjun Lu,Guo-Cheng Han
The Na 3 V 2 (PO 4 ) 2 F 3 /Co/N-PC composite was prepared based on nitrogen-doped porous carbon materials containing cobalt (Co/N-PC), which is obtained through high-temperature pyrolysis of bimetallic Co/Zn-MOF. The electrochemical test results showed that the discharge specific capacity of Na 3 V 2 (PO 4 ) 2 F 3 /Co/N-PC composite was 126.66 mAh/g at 0.1C, an increase of 15.6 % compared with Na 3 V 2 (PO 4 ) 2 F 3 /N-PC(109.56 mAh/g). The capacity retention rate was 91.84 % after 100 cycles and the R SEI of the Na 3 V 2 (PO 4 ) 2 F 3 /Co/N-PC composite (48.62 Ω) outperforms that of the Na 3 V 2 (PO 4 ) 2 F 3 /N-PC composite (81.55 Ω). This work applied the metal/carbon hybrid materials obtained through high temperature pyrolysis of bimetallic organic frameworks were employed in sodium-ion batteries, thereby offering enhanced potential for the advancement of sodium-rich phosphoric acid modified materials.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2023
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IF 7.2
Lijuan Peng,Xiaomin Peng,Zhaogen Zhu,Qianqun Xu,Kaifen Luo,Zhaotong Ni,Dingsheng Yuan
Developing the low-cost, durable, and efficient bifunctional electrocatalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) plays an important role in the commercial implementation of the Zn-air batteries. Herein, we design and synthesize the MnO and Co nanoparticles coated with N-doped carbon (MC@NC) as an excellent bifunctional oxygen electrocatalyst. It is found that the optimal MC@NC-0.3 exhibits outstanding ORR performance with a positive half-wave potential of 0.82 V and excellent OER activity with a small overpotential of 360 mV at 10 mA cm −2 . When applied in the liquid Zn-air battery, MC@NC-0.3 displays a high maximum power density of 153 mW cm −2 , a large specific capacity of 776 mAh g −1 and the excellent cycling stability with a negligible increase after 300 h. Furthermore, the fiber-shaped all-solid-state Zn-air battery also displays remarkable stability at high current density . This study offers a facile strategy to construct a high-efficient, low-cost, and durable transitional metal-based bifunctional electrode for renewable energy applications .
研究领域:
材料科学
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电化学
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
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2018
·Vol. 20
·期 15
·3593-3603
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IF 8.586
Shenghui Zhou,Guixian Chen,Xiao Feng,Ming Wang,Tao Song,Detao Liu,Fachuang Lu,Haisong Qi
Herein, we report a sustainable route to in situ synthesize a monolithic MnOx/N-doped carbon aerogel catalyst (Mn-NCA) by pyrolysing MnO(OH)2-cellulose aerogel precursors based on an alkali–urea aqueous system. The as-obtained Mn-NCA showed highly efficient catalytic activity for the transfer hydrogenation of a broad range of biomass-derived aldehydes, yielding 90–100% conversion and 64–100% selectivity to the corresponding alcohols under mild conditions in an oven without agitation. A combination of controlled experiments and detailed characterization studies indicated that the superior performance of Mn-NCA is attributed to the monolithic three-dimensional (3D) hierarchical porous architecture and the synergistic effects between homogeneously dispersed MnOx nanoparticles (NPs) and urea-derived basic sites. The monolithic feature of Mn-NCA exhibits superior dispersibility and separability compared to conventional centrifugation and filtration techniques in a powdery catalytic system. Moreover, a possible reaction mechanism is proposed. Our work provides a new method for developing highly efficient monolithic catalysts from renewable biopolymers for biomass valorization.
研究领域:
材料科学
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催化化学
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可再生资源利用
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
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2025
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IF 5.5
Na Jin,Xiao Yang,Yong Li,Wanjing Lai,Hailin Jiang,Yanghua Li,Kuo Liu,Yimeng Cai,Linjie Zhang,Lili Han
Hydrogen, characterized by its high energy density, efficiency, and environmentally benign output, emerges as a promising alternative to fossil fuels. However, the development of robust hydrogen oxidation reaction (HOR) catalysts for efficient energy conversion remains a significant challenge. Herein, a NiRu nanoalloy catalyst supported on N-doped hollow carbon nanocages (NiRu/NC) is synthesized via a tandem pyrolysis method. The NiRu/NC catalyst exhibits superior alkaline HOR activity, achieving diffusion-limited current density of 2.56 mA cm–2 and maintaining stability for 80,000 s with a decay rate of only 5.9%, compared to a 28.7% decay rate for benchmark Pt/C after 35,000 s. Additionally, it demonstrates remarkable resistance to CO poisoning, with the current density decreasing by only 50.7% after 1800 s, while the current density of Pt/C dropped to 0 after 800 s. Density functional theory calculations indicate that Ni in the NiRu nanoalloy effectively modulates the electron distribution, thereby ameliorating the electronic structure and enhancing the adsorption of reaction intermediates. These optimizations endow NiRu/NC with both favorable hydrogen-binding energy (HBE) and hydroxyl-binding energy (OHBE), leading to improved HOR efficiency. This work not only offers an innovative approach for synthesizing high-performance alloy-based HOR catalysts but also deepens the fundamental understanding of the bimetallic synergistic mechanisms in HOR catalysis.
研究领域:
材料科学
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电催化
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能源转换
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
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2024
·Vol. 14
·期 4
·279
·
IF 3.8
Yan Wang,Wuxin Liu,Rongzhe Wang,Qing Wang,Shaohua Luo,Pengqing Hou,Yahui Zhang,Shengxue Yan,Xin Liu,Jing Guo
Fe/N-doped carbon (Fe-NC) is an excellent base-metal catalyst for use in an electrocatalytic oxygen reduction reaction (ORR) with high activity. In this paper, graphite phase carbon nitride (g-C3N4) was first obtained from the pyrolyzing of melamine, and then different proportions of FeCl3were separately doped into g-C3N4to further prepare the Fe-NC catalyst. The Fe-NC catalyst was applied in an ORR reaction, and the results show that the Fe-NC catalyst doped with 0.5 mmol FeCl3possesses exceptional electrocatalytic performance, with an onset potential of 0.96 V and a half-wave potential of 0.81 V, which approaches that of a Pt/C catalyst. Meanwhile, the Fe-NC catalyst displays high stability and methanol resistance. The results supply a new way to prepare efficient ORR electrocatalysts.
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
MICROCHIMICA ACTA
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2020
·Vol. 187
·期 10
·1-9
·
IF 6.232
Luo Guiling,Deng Ying,Zhu Lin,Liu Juan,Zhang Bingxue,Zhang Yan,Sun Wei,Li Guangjiu
A core-shell ZIF-8@ZIF-67 was synthesized and pyrolyzed to get a Co nanoparticles-embedded N-doped carbon nanotube hollow polyhedron (Co@NCNHP). Then Au nanoparticles were formed on the surface and core of Co@NCNHP to obtain an Au-Co bimetal decorated NCNHP (Au-Co@NCNHP). The resultant nanocomposite was characterized by various methods including transmission electron microscopy, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The Au-Co@NCNHP-based electrochemical sensor displayed an obviously high electrocatalytic response to the oxidation of quercetin, which was attributed to the synergistic effects of Au-Co bimetal nanoparticles and N-doped carbon nanotube with hollow polyhedron. Under the optimal conditions, the oxidation peak currents exhibited a wide linear dynamic range for quercetin concentration from 0.050 to 35.00 μmol/L, and the detection limit was 0.023 ± 0.002 μmol/L (S/ N = 3). The analytical applications of the proposed electrochemical sensor were checked by determining the content of quercetin in medical and onion samples with satisfactory results.
Grapical abstract
研究领域:
材料科学
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分析化学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2019
·
IF 0
Fu Chen,Hui Luo,Yongzhi Cheng,Jieling Liu,Xian Wang,Rongzhou Gong
Electromagnetic (EM) interference and radiation affecting human health and the operation of precision electronic devices have drawn considerable attention in recent years. Herein, a promising microwave-absorbing material, Ag nanoparticles (AgNPs)-decorated Fe/Fe3O4@N-doped carbon (NC) composite, was designed and fabricated with the Fe2O3@polydopamine@Ag hexagonal plates as the precursor. Crystalline structure, phase conversion, micromorphology, static magnetic properties, and EM characteristics of the samples were studied by various analytical techniques. The EM parameters of the obtained samples could be manipulated by increasing the pyrolysis temperature, exhibiting gradually enhanced dielectric and magnetic loss. Optimizing the coating thickness turns out to be a critical factor for regulating microwave absorption. The product obtained at 600 °C performs a maximum reflection loss (RL) value of −37.5 dB (10.64 GHz, 1.6 mm) and an effective absorption bandwidth (RL < −10 dB) up to 7.36 GHz (10.64–18 GHz) with a thickness of only 1.4 mm. In addition, the possible EM wave absorption mechanisms were further investigated in detail. In sum, it has been confirmed that the as-obtained AgNPs-decorated Fe/Fe3O4@NC composite with ultrabroad absorption bandwidths and strong absorption capacity would be an attractive candidate material for effective EM absorption materials in the future.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
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
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材料科学
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催化
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能源材料
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可持续能源
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）