CERAMICS INTERNATIONAL
·
2023
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IF 5.2
Xingang Luan,Qinghua Zhao,Shaomin Gu,Xichao Dong,Laifei Cheng,Ralf Riedel
Wireless passive sensors based on surface acoustic wave (SAW) provide a good solution for the measurement demand under high temperature and harsh conditions. SiBCN ceramics have excellent mechanical properties at high temperature and semiconductor behavior, making them potential for electrode of SAW sensors. To achieve the target conductivity, a series of SiBCN and SiNiBCN coatings are prepared by polymer derived ceramics (PDC) method and the influence of microstructure on the conductivity of the coatings is discussed. The results show that the conductivity of the SiBCN coatings is affected by both the content of free carbon and the degree of graphitization. The introduction of Ni leads to the formation of Ni 2 Si conductive microcrystals at lower temperatures and catalyzes the graphitization of the carbon phase, so that the SiNiBCN coatings show lower electrical resistivity. The amount of the metal conductive phase and the graphitization degree of the carbon phase increase with the pyrolysis temperature, resulting in decrease of the SiNiBCN coatings resistivity.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
Scientific Reports
·
2020
·Vol. 10
·期 1
·1-15
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IF 3.998
Zhou Qiying,Chen Wenhua,Jiang Xia,Liu Hongying,Ma Shenggui,Wang Bangda
A novel nitrogen-containing graphitic mesoporous carbon was prepared through MnO-templated method using polyacrylonitrile (PAN) as both carbon and nitrogen sources, and MnCO 3 as both template and catalyst precursors. The effects of preparation conditions on the physicochemical properties of obtained samples were systematically investigated. The results showed that as the decrease of the weight ratios of PAN and MnO (2:1–1:4), the increase of carbonization temperature (700–900 °C) and pre-oxidation temperature (180–200 °C), the samples had higher specific surface area, mesopores volume and ratios, up to 507 m 2 /g, 0.824 cm 3 /g and 96.83%, respectively. Moreover, the prepared samples presented relatively high graphitic degree and nitrogen contents (~2.21%). The adsorption capacity for acid red 88 (AR88) was as high as 309 mg/g, which were dramatically affected by the mesoporous properties and C- and N-containing groups on the surface of prepared carbon. The rich graphic carbon and pyridine-N in mesoporous carbon generated π-π dispersion and electrostatic interaction with AR88, respectively, which jointly were responsible for the adsorption process. The results of the isotherm and kinetic studies indicated that the AR88 adsorption on mesoporous carbon could be well depicted using Langmuir model and pseudo-2 nd -order model.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2023
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IF 3.8
Pengfei Liu,Wenqiao Du,Xiangjing Liu,Long Zhang,Zhimin Chen
Common strategies for catalytic graphitization of biochar into graphitic porous carbon (GPC) still face great challenges, such as the realization of simple procedures, energy conservation, and green processes. Controlling over the graphitization degree and pore structure of biochar is the key to its structural diversification. Herein, a clean and energy-efficient method is developed to synthesize adjustable graphitic degree and structure porosity GPC from rice husk-based carbon (RHC) at a relatively low temperature of 800–1000 °C with environment-benign organometallic catalyst EDTA-iron and the recovery ratio of catalyst is as high as 97%. The formed by the organic ligands of EDTA-iron facilitates the etching of RHC surface and pore by iron, resulting in highly graphitized and developed porous GPCs. The pore structure and graphitization degree of GPCs can be adjusted by altering the catalyst loading, temperature, and holding time. The catalyst EDTA-iron with a lower concentration mainly plays the role of etching, which promotes the formation of porous carbon with larger surface area ( S BET =1187.2 m 2 ·g –1 ). The catalyst with higher concentration mainly plays the role of catalyzing graphitization and promotes the obtaining of graphitic carbon with high graphitization degree ( I D / I G =0.19). The mechanism of EDTA-iron catalyzed graphitization of RHC is explored by the comprehensive analysis of BET, XRD, Raman, TEM and TGA. This research not only provides an efficient method for the preparation of high-quality biomass-based graphite carbon, but also provides a feasible method for the preparation of biomass-based porous carbon.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Yunfei Chen,Mingyong Wang,Songle Lu,Jiguo Tu,Shuqiang Jiao
s Electrochemical conversion of CO 2 to carbon in molten salts is a promising route for the high-value utilization of greenhouse gases . Low graphitization degree of carbon materials is the limiting issue for potential applications. In the past, catalytic effect for the electrochemical conversion of CO 2 was not achieved in molten salts due to carbon coverage on heterogeneous solid electrode. A novel and feasible homogeneous catalytic strategy by soluble NaVO 3 in carbonate molten salt was proposed for the enhanced electrochemical conversion of CO 2 to carbon with high graphitization degree. It was found that graphite consisting of carbon nanotubes and sheets were more easily produced by adding NaVO 3 into molten salt. The graphitization degree of carbon products was obviously improved and I D / I G value was only 0.428. During CO 2 electrolysis, vanadate in the form of V 2 O 7 4− will be co-electroreduced to V 2 O 3 . Meanwhile, V 2 O 7 4− ions can be regenerated by the spontaneous reaction between the newly-formed V 2 O 3 and carbonate, which also accelerates the production of graphite. Therefore, a continuous homogeneous in-situ catalytic cycle was achieved for the enhanced graphitization conversion of CO 2 . It provides a novel and effective way to prepare carbon materials with high graphitization degree from CO 2 .
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2015
·
IF 4.504
Xing Xu,Yunlong Xu,Huang Zhang,Mandi Ji,Hui Dong
The NiO doped LiFePO 4 /C composite was synthesized by a simple solid state method. The structure and morphology of synthesized particles were characterized by XRD, Raman spectrum , SEM, TEM and EDS. Electrochemical performance of the pristine and nickel oxide modified samples was evaluated by galvanostatic charge-discharge test, CV , and EIS . The results indicate that NiO doped LiFePO 4 /Li type coin cell exhibits improved specific capacity and cycle stability, especially at high rates. Among all the modified samples, the 5.0%wt NiO doped sample shows the best electrochemical performance, which achieves a specific capacity of 129 mA h g −1 at 1 C current rate due to the modest graphitization of carbon layer on the surface of LiFePO 4 particles. The results indicate that nickel oxide modification is an effective way to improve the electrochemical performance of LiFePO 4 /C cathode materials for lithium ion batteries .
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2023
·
IF 9.4
Chun-Feng Xue,Xiao-Qing Li,Jian-Qiang Du,Li-Feng Wang,Xiao-Hong Li,Wen-Jun Yan,Xiao-Gang Hao
To enhance energy density of water-based electrochemical supercapacitor , a highly self-graphenized bicohar with huge pore volume is pyrolyzed from the biomass Ulva lactuca (UL) pre-boiled in Mg(CH 3 COO) 2 solution. During the pyrolysis process , the MgO converted from the Mg(CH 3 COO) 2 re-crystallized in the biomass UL inhibits the pore shrinkage and helps to inherit the pristine pore system . The resultant biochar HUB-2.0 exhibits high specific surface area (SSA) of 2296.7 m 2 g −1 and huge pore volume of 4.59 m 3 g −1 . It is also featured with moderate self-graphenization and heteroatoms self-doped surface in the connected pore system inherited from the precursor. It achieves a specific capacitance of 445.0 F g −1 at 0.5 A g −1 in the three-electrode system with the electrolyte 1.0 M H 2 SO 4 . A superior energy density of 27.17 Wh kg −1 is also calculated at a power density of 222.8 W kg −1 in the two-electrode system with the neutral electrolyte Na 2 SO 4 . The work provides a fast and efficient method to prepare the biochar with balanced properties to achieve superior electrochemical supercapacitor performance, especially for high energy density.
研究领域:
材料科学
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能源存储
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2025
·
IF 3.7
Yuwei Deng,Qing Long,Yifan Gao,Kefei Chen,Hongyuan Sheng,Yajun Wang,Angang Dong
The durability of proton-exchange membrane fuel cells is often compromised by the corrosion of carbon supports in oxygen reduction reaction (ORR) cathodes under harsh operating conditions, including high oxygen concentration, elevated humidity, low pH, and high potentials. To overcome this limitation, we report the synthesis of a 2D mesoporous graphitic nanocarbon framework (MGF) via chemical etching and high-temperature graphitization. The resulting MGF features a monolayer, highly ordered nanoframe architecture that offers enhanced structural stability and conductivity. Leveraging these structural advantages, we designed fully exposed Pt nanoparticles anchored on the MGF (Pt@MGF) as a model system to investigate the interplay between graphitization degree, pore architecture, and electrocatalytic performance. Among the variants, Pt@MGF-1200, synthesized at 1200 °C, demonstrates optimized mesopore confinement and strong Pt–carbon interactions. This results in superior electrochemical durability and ORR activity, positioning Pt@MGF-1200 as a promising alternative to conventional Pt/C catalysts. Graphical In this work, a novel 2D mesoporous graphitic nanocarbon framework (MGF) is synthesized through chemical etching of 2D Fe 3 O 4 nanocube superlattices (Fe 3 O 4 NCSLs) and subsequent high-temperature graphitization. MGF possesses large specific surface area, open porous architecture, and high graphitization degree, making it an excellent platform for constructing Pt-based ORR electrocatalysts. The resulting Pt@MGF catalyst exhibits superior ORR activity and durability over commercial Pt/C catalysts.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Zhaoyi Han,Hao Shi,Wentao Qiu,Dongdong Zhu,Wei Li,Dihua Wang
The excessive use of antibiotics like sulfamethoxazole (SMX) is causing environmental pollution and endangering human health and the ecosystem. Using transition metals as catalysts to activate persulfate (PS) can effectively degrade the organic pollutants in the advanced oxidation process (AOP). However, the high dissolution of the transition metals leads to poor stability, low efficiency in pollutant degradation, and secondary pollution. In this work, a graphitized carbon encapsulated Co (Co@EC) anode is developed for electrochemically activating peroxymonosulfate (PMS) to degrade SMX. It is found that the synergistic effect of Co@EC, PMS, and current significantly enhances SMX degradation. Under optimal conditions (current density of 5 mA cm −2 , pH of 9, and PMS concentration of 0.25 mM), the Co@EC anode can completely remove 10 μM of SMX in 9 min, a much higher efficiency compared to processes without PMS, Co, or current. The rapid reaction kinetics (6.69×10 −1 min −1 ) at optimal conditions are associated with the two main active species of 1 O 2 and O 2 • − during electroactivation. Furthermore, the Co@EC anode maintains high degradation efficiency and low dissolution after repeated cycling tests due to its structural stability. These findings provide new insights and strategies for developing stable catalysts.
研究领域:
环境科学
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电化学
·
催化材料
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Shuai Chen,Feng Wu,Haolin Wang,Shuang Gao,Jiafu Chen,Zhimin Chen,Jianwei Fu
Ferric oxide (Fe 2 O 3 ) has become one of the most competitive candidates for the next-generation lithium-ion batteries anode materials due to its high theoretical reversible specific capacity (Cs, 1007 mAh g −1 ) and low price. However, the rapid capacity fading and poor rate performance deriving from drastic volume expansion (∼200 %), low Coulombic efficiency (CE), and poor electrical conductivity limit its application in LIBs. Herein, a novel encapsulation structure of Fe 2 O 3 nanoparticles has been developed. Fe 2 O 3 nanoparticles inlaid in the shells of hollow highly graphitized carbon fibers are coated by N-doped graphitized carbon (GF-FeO@NGC) by a catalytic graphitization, oxidation route of Fe-based catalyst. The GF-FeO@NGC electrode shows the first specific discharge/charge capacities of 1355/974 mAh g −1 with high initial Coulombic efficiency (ICE) of 72.0%, and excellent reversibility of lithiation/delithiation reaction. After 200 cycles at 0.1 A g −1 , the GF-FeO@NGC electrode keeps a high reversible Cs of 918 mAh g −1 (retention of 94.3%) with a CE of 99.6%. It is noticeable that the GF-FeO@NGC electrode has good rate performance and robust cycling stability at high current density. After 300 cycles at 2 A g −1 , the Cs retention is up to 97.1% with a CE of 99.7%. These are far superior to those of the GF-FeO (without NGC coating) and the most reported Fe 2 O 3 -based electrode materials. The mechanism behind these phenomena are studied.
研究领域:
材料科学
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电化学
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能源存储
·
纳米技术
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Yunxiao Jia,Bohao Peng,Xinyi Li,Shifang Huang,Xiaosong Zhang,Yulong Ding,Zhu Jiang
Low thermal conductivity is one of the key defects of pristine phase change materials (PCMs) for solar thermal energy storage. Biomass derived carbonaceous matrix, which could be recycled from wide sources, are favourable to incorporate with PCMs for solar thermal storage applications for their highly porous structure and decent thermal properties. Their unique structures get from the grown plants also endue them with diverse properties and functions, such as anisotropic thermal properties for directional heat transfer. However, direct pyrolysis of biomass generally produces amorphous carbonaceous structure that suffers insufficient thermal conductivity. Therefore, this work proposed a simple, rapid, and effective Fe graphitisation route to derive pine wood as graphitic matrix to synthesize multifunctional shape stabilized composite PCM. The Fe graphitisation process has induced the conversion of amorphous carbon to well-ordered graphitic structure. Further elevating the catalytic temperature contributes to a high graphitisation degree up to 89.53 %. With this Fe graphitisation route, the thermal conductivity of PCM composite at its longitudinal direction has increased from 0.545 W · m −1 K −1 to 1.846 W · m −1 K −1 . The solar absorptivity has reached up to 95.60 %. Besides, a high amount of PCM (∼72.26 wt%) was retained by the matrix, offering a high endothermic enthalpy up to 154.2 J/g. In the meantime, the aligned tubular structure of graphitic matrix leads to an anisotropic heat transfer behaviour, displaying a greater thermal conductivity along the longitudinal direction. Therefore, this study has provided a new approach to fabricate high-performance biomass derived graphitic matrix based PCM composite for solar thermal storage applications.
研究领域:
材料科学
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能源工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Biochar
·
2023
·Vol. 5
·期 1
·1-14
·
IF 12.7
Chen Chao,Sun Kang,Huang Chen,Yang Mengmei,Fan Mengmeng,Wang Ao,Zhang Gaoyue,Li Bei,Jiang Jianchun,Xu Wei,Liu Junli
The structural reconstruction mechanism of lignin and cellulose-derived biochars during direct graphitization under ultra-high temperatures was intensively investigated. It was demonstrated that cellulose-derived char was almost composed of carbon microcrystallites, whereas lignin-derived char reserved some of its skeleton structures, and such structural difference played a vital role in the morphology of formed graphitic layers. The results illustrated that the graphitized lignin-derived sample under 2800 ℃ had graphitic degree of 89.53%, interlayer spacing of 0.3363 nm and electronic conductivity of 104.6 S cm −1 , while cellulose-derived sample had graphitic degree of 76.74%, layer distance of 0.3374 nm, and electronic conductivity of only 48.8 S cm −1 . Combined with the results of structural analysis of the chars derived from lignin and cellulose, it was inferred that the stable and aromatic ring containing skeleton structure in lignin was beneficial to the ring-enlarging reconstruction and the formation of large areas of continuous graphitic layers during graphitizing process, leading to high electronic conductivity. Meanwhile, the interwoven microcrystallites in cellulose-derived char strongly restricted the expanding of continuous lamellar graphitic areas even at such ultra-high temperature, causing the formation of turbostratic structure with numerous structural defects as well, and finally resulting in relatively lower electronic conductivity. This work is expected to provide theoretical guidance for preparing high-performance functional carbon materials from lignocellulosic biomass. Graphical Abstract
研究领域:
材料科学
·
生物质能
·
碳材料
✓ 已验证
产品关联
DOI
高影响因子
Environmental Technology & Innovation
·
2024
·
IF 6.7
Xiaotong Zhang,Jinju Hou,Tong Cai,Shudong Zhang,Lichun Shen,Qiuzhuo Zhang
Designing biochar for the efficient removal of specific pollutants remains a significant challenge. In this work, a graphitized biochar with large carbon clusters (HBC700) was synthesized specifically for the removal of tetracycline. HBC700 exhibited outstanding adsorption performance, with a maximum adsorption capacity of 257.04 mg·g⁻¹, which is 4.72 times that of the pristine biochar. The superior performance is attributed to its low electrical resistance, which facilitates electron transfer at the interface, enabling rapid and efficient tetracycline removal. After tetracycline adsorption, the structure of HBC700 became more ordered, forming a stable honeycomb arrangement. HBC700 also demonstrated high regeneration stability, maintaining a 94.85% removal rate after five cycles, and achieving 100% removal after H₂O₂ purification. Furthermore, HBC700 achieved over 98% tetracycline removal in both tap water and wastewater, highlighting its potential for real-world applications.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）