SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Zhenzhong Liu,Suyue Luo,Xinran Yin,Shuo Zhang,Minghui Guo
The present work effectively achieved the production of a self-supporting electrode with high efficiency. The process involves incorporating nickel and molybdenum carbide (Mo 2 C) phases within the channels of wood through high-temperature calcination at the nanoscale. The obtained carbonized wood (CW) possesses low tortuosity and three-dimensional vertical channels, providing an excellent substrate for the preparation of Ni-Mo 2 C/N-CW electrodes. Mo 2 C is well known for its considerable potential as a non-precious metal electrocatalyst with enhanced catalytic activity. The successful doping of nickel and nitrogen into molybdenum carbide not only promotes the formation of β-Mo 2 C, but also improves the electron transfer rate and mass diffusion pathway. Consequently, the Ni-Mo 2 C/N-CW electrode exhibits excellent performance in the hydrogen and oxygen evolution reactions (HER and OER, respectively). Only voltages of 89 and 253 mV are required to achieve a current density of 10 mA cm −2 , respectively. When the Ni-Mo 2 C/N-CW catalyst is used as both cathode and anode during hydrolysis, current densities of 10 and 100 mA cm −2 can be achieved with excellent durability and stability at voltages of 1.56 and 1.72 V, respectively. The distinctive porous structure of the wood substrate is of crucial importance for promoting the adsorption and dissociation of water molecules, enhancing the catalytic performance. In addition, the present material exhibits advantageous characteristics, including a high specific surface area and a significant number of adsorption sites, making it a very promising candidate for applications involving the adsorption of dyes, such as rhodamine B (RhB).
研究领域:
材料科学
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电化学
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环境科学
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 3.7
Chen Liang,Weiqiang Chen,Linghong Yin,Xianli Wu,Jie Xu,Chunhua Du,Wangda Qu
Lignin has been proved to be a promising precursor for producing carbon foam. The thermal and chemistry properties of lignin during its thermal conversion make it quite unique comparing with other precursors, and the conversion parameters can clearly affect the properties of the derived products. Therefore, this study systematically investigated the effects of key carbonization parameters on the properties of the resulting carbon foam materials. The findings demonstrate that the performance of the self-shaping lignin-derived carbon foam is simultaneously influenced by the factors that carbonization temperature, heating rate, and carbonization duration. Specifically, the carbonization temperature and carbonization duration have a significant impact on the mechanical performance, where higher temperatures and long carbonization time improve compressive strength and specific strength. Moreover, the data revealed that elevated temperatures, rapid heating rates, and shortened carbonization periods collectively promoted the development of higher porosities and larger pore diameters within the carbon foam structure. Conversely, lower carbonization temperatures, slower heating rates, and extended carbonization durations facilitated the formation of microporous in the carbon foam. This study provides a scientific foundation for optimizing the production of lignin-derived carbon foam with tailored properties and performance characteristics.
研究领域:
材料科学
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化学工程
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Jie Dang,Yijie Wu,Zepeng Lv,Xuewei Lv
Tungsten carbides , which can be widely used as cutting and drilling tools, chemical catalysts and aerospace coatings, have attracted widespread attentions. The present work reported a simple method to prepare tungsten carbides by using WO 2 as the raw materials and CO as the reduction and carbonization agent. It was found that at lower and moderate temperatures, all the final product was WC, while at higher temperatures, the final products were W 2 C or W. The reduction and carbonization mechanism was also studied theoretically and experimentally. WO 2 was reduced and carburized to WC in one step at lower temperatures; WO 2 was first reduced and carburized to W 2 C and then to WC at moderate temperatures; while at higher temperatures, WO 2 was first reduced to metallic W and then carbonized to WC or W 2 C, but with the temperature increasing, the carbonization became difficult and required much higher CO content.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Mengen Hu,Xincan Gao,Zhen Wang,Xian Dang,Chengwan Yang,Xinyang Li,Ming Li,Yue Li,Xiaoye Hu,Zhulin Huang
Tungsten carbide (WC) cemented carbide plays a crucial role in cutting and mechanical processing. However, the grain coarsening that inevitably occurs during the high temperature sintering process of WC leads to a reduction in mechanical properties. This study presents a strategy for the one-step synthesis of tantalum carbide (TaC) grain inhibitors to enhance ultrafine grain WC ceramics. Specifically, WC-xTaC (where x = 0 wt%, 1 wt%, 2 wt%, 3 wt%, and 4 wt%) powders were synthesized directly in one step using a liquid phase method, thereby eliminating the effects of the ball milling process on the defect density and surface energy of the powders. The mechanical properties of the sintered blocks were evaluated after the synthesized WC-xTaC powders underwent hot press sintering. The results demonstrate a reduction in the grain size of WC from 1.96 μm to 850 nm after sintering compared to WC ceramics without TaC doping. The density of the material improved from 91.4 % to 97.8 %, while the hardness increased from 16.3 GPa to 24 GPa, reflecting an overall enhancement of 47.2 %. This research provides an optimized approach for the fabrication of ultrafine grained WC ceramics.
研究领域:
材料科学
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陶瓷工程
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DOI
高影响因子
CORROSION SCIENCE
·
2020
·
IF 6.479
Tao Feng,Mingde Tong,Shuotian Yao,Hejun Li,Hongjiao Lin,Shifeng Wen,Peipei Wang
The B-modified SiC/HfC-SiC composites were prepared by the combination of precursor infiltration and pyrolysis (PIP) and chemical vapor deposition (CVD) methods. The microstructure, cyclic ablation and bending strength tests of the SiC/HfC-SiC composites with and without B were investigated. The results showed that the B-modified composites had a better cyclic ablation resistance than that of the composites without B. The effective residual thickness of the B-modified composites was also higher than that of the composites without B after cyclic ablation. The residual bending strength of the B-modified composites was slightly lower than that of the composites without B.
研究领域:
材料科学
·
航空航天工程
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DOI
高影响因子
CEMENT AND CONCRETE RESEARCH
·
2024
·
IF 10.9
Miao Ren,Peiliang Shen,Yong Tao,Chi-sun Poon
Carbonation of calcium silicate (CS) minerals to produce hardened construction materials has attracted increasing interest, but the efficiency of conventional CS minerals is low. This study prepared a highly reactive β-C 2 S derived from a C-S-H precursor through hydrothermal synthesis . The potential CO 2 uptake ability, product compositions, microstructural characteristics , and carbonation mechanisms of the hydrothermal β-C 2 S were investigated. The results showed that the hydrothermal β-C 2 S achieved 3.7 times higher carbonation efficiency compared to the reference β-C 2 S prepared by traditional calcination and reached a carbonation degree of 56.1 % within 10 min. Its high reactivity was attributed to large specific surface area, unique thin lath structure, and fine grain size . The novel type of C-S-H produced, special thin lath structure evolution and sufficient ACC led to an almost complete carbonation degree of hydrothermal β-C 2 S. The developed carbonation process could be used to valorize recycled concrete waste which contains a large amount of C-S-H.
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
CELLULOSE
·
2024
·
IF 4.9
Lu JiaYu,Yu Jin,Jiang Ziqing,Zhang Yan,Zhang Hao,Yu Yihao,Qi Dongming,Wang Jianming
With the escalating prevalence of electromagnetic radiation pollution, flexible electromagnetic interference (EMI) shielding materials hold immense potential for widespread application. Carbonized fabric possesses notable advantages such as flexibility, excellent electrical conductivity, and chemica l stability. However, its traditional preparation process is characterized by high energy consumption, intricate atmospheric conditions, and prolonged duration. This study introduces a novel approach of incorporating intumescent flame retardant (IFR) into cotton fabric, aiming to facilitate rapid carbonization in an air atmosphere. Remarkably, this innovative approach yields an outstanding total EMI shielding effectiveness (SE T ) of 17.55 dB within a mere 5 min carbonization process at 900 °C under ambient air conditions. Moreover, in order to enhance the shielding effect, we conducted in-situ growth of polypyrrole (PPy) on the prepared carbonized fabric. The deposition time of 120 min resulted in an impressive SE T value of 28.22 dB, effectively providing a shielding capability of up to 99.9% against electromagnetic waves (EMW). Moreover, the SE T value of IFR-C-PPy-60 min can be enhanced to 51.84 dB by stacking 4 layers, enabling the attenuation of 99.999% of EMW. The IFR-C-PPy also demonstrated exceptional fire safety and thermal stability. This study presents a novel approach for the rapid and large-scale fabrication of highly efficient conductive carbonized fabric, which demonstrates potential applications in flexible electronic devices. Graphical abstract
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
FUEL
·
2018
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IF 4.908
Fei Wang,Jianchun Jiang,Kui Wang,Qiaolong Zhai,Hao Sun,Peng Liu,Junfeng Feng,Haihong Xia,Jun Ye,Zhengxiang Li,Fanglin Li,Junming Xu
The activated carbon supported Mo 2 C and W 2 C were synthesized successfully for hydrotreatment of fatty acids to produce diesel-like hydrocarbons. The carburization temperature, carburization gas as well as metal loading amount were studied. High carburization temperature was feasible for W 2 C/AC, but not for Mo 2 C/AC because it resulted in agglomeration of molybdenum compound and destruction of catalyst. Under hydrotreatment condition (360 °C, H 2 3.0 MPa, 3.0 h) the conversion achieved 96.01% over Mo 2 C/AC prepared at 700 °C and 54.88% over W 2 C/AC prepared at 900 °C respectively. During carburization both flowing nitrogen and hydrogen were proper for formation of W 2 C/AC, while only flowing hydrogen was appropriate for Mo 2 C/AC. The hydrotreatment parameters (reaction temperature and reaction time) were also investigated. The high reaction temperature and long reaction time facilitated the conversion of fatty acids, meanwhile the high reaction temperature simultaneously improved the cracking degree of products.
研究领域:
催化化学
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能源化学
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产品关联
DOI
高影响因子
Processes
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2020
·Vol. 8
·期 1
·120
·
IF 2.753
Erwei Pang,Weijun Liu,Shuhua Zhang,Nengshuo Fu,Zhongxun Tian
A good way to make carbon materials was presented in low-temperature polyvinyl chloride (PVC) carbonization by catalysis. The process of low-temperature PVC carbonization by CuAl-layered double hydroxide (CuAl-LDH) was investigated by thermogravimetric analysis (TGA) and tubular furnace. The results show that CuAl-LDH accounting for 5% of PVC mass enabled acceleration of the dehydrochlorination in PVC as soon as possible and maximized the yield of the PVC carbonized product. The vacuum with 0.08 MPa, 20 °C/min heating rate and 90 min carbonized maintenance time were optimal for PVC carbonization. Moreover, the best morphology and yield of the carbonized product was provided at a carbonization temperature of 300 °C.Keywords:catalytic PVC pyrolysis;PVC carbonization;CuAl layered double hydroxide (CuAl-LDH)
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Chang Xu,Xuan Zhao,Mengyao Sun,Jingyuan Ma,Mingxing Wu
In the present study, two typical 2D layered MXenes, i.e., Titanium carbide (Ti 3 C 2 ) and Vanadium carbide (V 2 C) are synthesized via a simple etching method under lower temperature as counter electrode catalysts to achieve the iodide redox couple regeneration in dye-sensitized solar cells. As indicated from the result, Ti 3 C 2 significantly outperforms V 2 C, and the device by exploiting Ti 3 C 2 counter electrode achieves power conversion efficiency (PCE) of 5.3%, while the device by applying V 2 C counter electrode only exhibits a poor PCE of 4.0%. To improve the catalytic activity of the prepared Ti 3 C 2 , the effect of etching time on the catalytic activity has been evaluated, which demonstrates that Ti 3 C 2 etched 24 h exhibits the highest catalytic activity, and the device generates a PCE of 6.2%. Lastly, the catalytic activity of the Ti 3 C 2 is further improved by postprocessing with KOH aqueous solutions, and the PCE value is up-regulated to 7.1%. The high catalytic behavior of Ti 3 C 2 could be attributed to the prominent charge transfer and mass transport properties caused by the specific 2D layer structure, suggesting a potential candidate to the noble metal electrodes.
研究领域:
材料科学
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能源科学
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化学工程
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2023
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IF 5.4
Meiyu Zhao,Yongsong Ma,Yu Zhang,Xianglin Liu,Haiou Sun,Renhe Liang,Huayi Yin,Dihua Wang
Titanium carbide (TiC) coating was prepared by in-situ carbonization of titanium using a novel salt-thermo-carburizing (STC) method in molten CaCl 2 -CaC 2 . The effect of the concentration of CaC 2 , the temperature of the melt and the reaction duration on the composition, structure and thickness of the carbide coating were systematically investigated. The optimized immersion bath was CaCl 2 –2 wt% CaC 2 at 900 °C. The thickness of the coating was increasing with the immersion time and it can reach 105 μm within 8 h. It was found that the growth kinetics of TiC coating follows a parabolic law in the temperature range of 850 to 900 °C, the obtained growth rate constants ( k ) is 1.43 × 10 −15 at 850 °C, 68.38 × 10 −15 at 875 °C, and 320.17 × 10 −15 m 2 /s at 900 °C, respectively. In addition, the microhardness of the TiC coating obtained at 850 °C and 8 h is over 740 HV, which is more than five times that of the Ti substrate. This work offers a universal and facile method to prepare metallic carbide coating on the respective metal substrate.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2024
·Vol. 53
·期 12
·7762-7772
·
IF 2.2
Dong Ziming,Dou Jiali,Ye Lin,Jiang Xihuan,Jiao Luwen,Liu Xiaojie,Wang Song
Slow carbonization (SC) and fast carbonization (FC) methods were applied and compared during the preparation of carbon materials using potassium citrate as raw material. The porous carbon material obtained by the SC method (SCPC800) had a slightly higher specific surface area than that obtained by the FC method (FCPC800). When SCPC800 was applied in the construction of a zinc–ion capacitor (ZIC), the obtained ZIC displayed a high mass specific capacitance (MSC) value of 309.5 F g −1 and a specific energy of 155.2 Wh kg −1 at the 0.2 A g −1 current density. FCPC800 showed similar electrochemical performance as SCPC800. The ZIC with the FCPC800 as electrode exhibited an MSC value of 300.7 F g −1 with a specific energy of 150.8 Wh kg −1 at the 0.2 A g −1 current density. Meanwhile, the SCPC800 and FCPC800-based ZICs showed good rate capability and cycle stability. Compared with the SC method, the FC method showed a significant advantage in reducing sample preparation time, which can greatly increase the preparation efficiency and reduce energy consumption. Therefore, as an efficient method, the FC method showed broad application prospects in the preparation of carbon materials for ZIC. Graphical Porous carbon materials prepared from potassium citrate for zinc-ion capacitor
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）