FUEL
·
2022
·
IF 8.035
Peng Liu,Yuanyuan Zhang,Tieying Pan,Dexiang Zhang,Lishi Chen,Changrong Sun
Coal conversion to material or chemical by pyrolysis is the main methods for achieving carbon neutrality. To predict correct pyrolysis behavior, accurately quantifying carbon structural types of complex coal discussed in this study is significative. Carbon structural types in coal based on 13 C NMR Cp/MAS TOSS spectra were accurately quantified by coupling standard curve and peak-fitting method to reduce nuclear overhauser effect (NOE). The H/C atomic ratio and aromaticity is used to verify the accuracy of this method. The pyrolysis behavior was predicted by pyrolysis Gas Chromatography-Mass Spectrometer (Py-GC-MS), thermogravimetric analysis (TG), and fix-bed slow pyrolysis according to correction carbon structure. The results show that the H/C atomic ratio calculated by correction carbon structure is agreed with that from ultimate analysis, as well as aromaticity. Their correction relative deviations are below 10%, farther lower than experimental value, increasing with the increment of C daf %. The correction carbon structure evolution during pyrolysis is coincided with general conclusion and Py-GC-MS analysis. The mono-aromatics and phenolics are evaluated by correction carbon structure. It is significantly fundamental study for carbon material to chemicals from micro-angle. These results are also a guide for accurate calculation and simulations of quantum chemistry.
研究领域:
能源科学
·
材料化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Powder Materials
·
2022
·
IF 0
Meng Li,Jingxue Sun,Gang Chen,Shuang Wang,Shunyu Yao
The CdS/Bi 2 S 3 supported three-dimensional (3D) porous faveolate carbon structure (CdS/Bi 2 S 3 @C) composite photocatalyst was constructed. Bi 2 S 3 nanoparticles are regarded as photothermal agents and pyroelectric materials to absorb near infrared light (NIR) and convert it into heat. 3D porous faveolate of carbon acts as incubator to reduce heat loss and optimize photothermal effects. There is a greater fluctuating temperature difference (Δ Τ ) between photothermal effect of Bi 2 S 3 and cold photocatalytic system. This enhances the pyroelectric effect that Bi 2 S 3 undergoes spontaneous polarization and releases the surface charge. Therefore, the separation of electrons and holes in the CdS photocatalyst can be induced. The COMSOL simulation results show that, the higher pyroelectric potential producted by larger Δ Τ is more favorable to the photocatalytic process. The hydrogen evolution rate of CdS/Bi 2 S 3 @C photocatalyst can reach 5.88 mmol·g − 1 ·h −1 with excellent cycle stability.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
ENERGY & FUELS
·
2021
·
IF 3.605
Shuai Chen,Wei Zhou,Yani Ding,Guangbo Zhao,Jihui Gao
Understanding the evolution of carbon structure in coal-assisted water electrolysis for hydrogen production (CAWE) is essential for seeking strategies to improve the rate of CAWE and getting more insight into the potential significance of CAWE. In this work, 13C nuclear magnetic resonance (NMR) is used to make out the evolution of carbon structure in CAWE. First, the electrolysis characteristics of three different-rank coals are revealed using electrochemical methods. Then, before and after electrolysis, the evolution of carbon structure is analyzed. The results show that CAWE is a process of reducing carbon and increasing oxygen, and the accumulation of oxygen-containing groups is mainly owing to the increase of oxygen aliphatic carbons and oxygen aromatic carbons. After CAWE, the aromatic cluster size decreases and increases for low-rank coals and high-rank coals, respectively.
研究领域:
能源科学
·
材料化学
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2020
·
IF 4.982
Tiankai Zhang,Yongfa Zhang,Qi Wang,Xuemei Lv,Yunhuan Luo
In this paper, the changes in solid-phase carbon structure and the formation of carbon nanotubes in the process of K-catalyzed pyrolysis of bituminous coal were investigated. The results showed that the content of carbon nanotubes in K-catalyzed coal pyrolysis products increased with the extension of residence time. When the residence times were 0, 30 and 90 min, the yields of carbon nanotubes in the coal pyrolysis products were 1.98 wt%, 6.85 wt% and 10.16 wt%, respectively. It was found that the aromatic carbon C C, C H and ether carbon C-O-C structures in coal were the main carbon sources for the growth of carbon nanotubes. The probable growth mechanism of carbon nanotubes in the process of K-catalyzed coal pyrolysis was proposed to be as follows: aromatic C C and C H structures in coal convert K components such as K 2 CO 3 and K 2 O into metal K, and then metal K converts carbon atoms in the ether bond C-O-C structure into carbon atoms or clusters, which generate carbon nanotubes under the action of Fe catalyst particles in coal. This method provides a new strategy for the simultaneous high-value utilization of coal resources and macroscopic, low-cost preparation of carbon nanotubes.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Gang Chu,Jing Zhao,Yang Liu,Di Lang,Min Wu,Bo Pan,Christian E.W. Steinberg
Biochar, a carbon-rich material, has attracted immense attention owing to its applications in soil remediation. However, the mechanisms by which heterogeneous carbon structures of biochars immobilize organic contaminants are not yet fully understood. In this study, the noncondensed aromatic components in biochars were selectively removed through bleaching. Different techniques, such as 13 C nuclear magnetic resonance, were applied to characterize the biochar compositions, and thus the role of the different carbon structures in organic contaminant sorption was discussed. The aromatic carbon structures in biochars were gradually developed and evolved from noncondensed to condensed structure with increasing pyrolytic temperatures from 300 to 700 °C. Based on elemental analysis, the carbon removed by bleaching decreased from 43.9% to 5.92% with increasing temperatures. After the surface area normalization of the apparent sorption, bleaching increased the sorption of carbamazepine and bisphenol A on biochars produced at 500 °C, but not for those produced at 300 and 700 °C. Bleaching removed noncondensed aromatics and enriched condensed aromatics, which resulted in increased sorption. However, bleaching also resulted in the blockage of micropores in biochars with abundant condensed aromatics, causing decreased sorption. The apparent sorption was determined by the balancing of these two opposite effects.
研究领域:
环境科学
·
土壤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Can Zhang,Xueying Fan,Jian-Tang Jiang,Cong Dou,Yuexing Liang,Xueai Li,Zhenjie Guan,Hongbo Xu,Yuan-Xun Gong,Wenzhu Shao,Cheng-Yan Xu,Liang Zhen
Multispectral absorbing materials that can efficiently dissipate waves across the visible, infrared, and microwave regimes have long been pursued for advanced applications in fields such as space exploration, stealth, and camouflage. However, the wide range of incident wavelengths, spanning five orders of magnitude, presents a significant challenge for the practical implementation of multispectral absorbers. Herein, superblack carbon hierarchitectures (SCHs) are designed using a bottom-up approach involving the self-assembly and self-sacrifice of hydrogen-bonded organic frameworks (HOFs), realizing synergistic morphological customization and dielectric gene editing (via carbon nitride like-moieties conjugated with C═C short chains). Through the cross-dimensional coupling action between light-trapping hierarchitecture and robust dielectric loss, superb visible light absorption (>99.6%), high infrared absorption (98.5%/97.5%/99.6% for long-/mid-/short-wavelength infrared regimes), and ultrabroad microwave absorption (effective bandwidth of 8.52 GHz, nearly covering both the X and K u bands) can be simultaneously achieved in monolayer SCHs-based absorbers. Furthermore, the topologically transformed structures of SCHs enable a systematic dissection of the longstanding ambiguity surrounding the geometrical effect, revealing the synergistic influence of fractal dimension and interconnection status of microparticles, particularly in the microwave regime. This work introduces a new paradigm for multispectral absorption and advances the understanding of absorption mechanisms for developing next-generation absorbers.
研究领域:
材料科学
·
光学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale Research Letters
·
2018
·Vol. 13
·期 1
·1-9
·
IF 3.125
Tan Xianhua,Shi Tielin,Lin Jianbin,Sun Bo,Tang Zirong,Liao Guanglan
We propose a novel one-step exposure method for fabricating three-dimensional (3D) suspended structures, utilizing the diffraction of mask patterns with small line width. An optical model of the exposure process is built, and the 3D light intensity distribution in the photoresist is calculated based on Fresnel-Kirchhoff diffraction formulation. Several 3D suspended photoresist structures have been achieved, such as beams, meshes, word patterns, and multilayer structures. After the pyrolysis of SU-8 structures, suspended and free-standing 3D carbon structures are further obtained, which show great potential in the application of transparent electrode, semitransparent solar cells, and energy storage devices.
研究领域:
材料科学
·
光学工程
·
微纳制造
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2023
·
IF 6
Qingqi Zheng,Zhiyu Li,Tianyang Guo,Qingwen Fan,Song Hu,Jun Xiang,Peng Fu
To gain new insights into lignin pyrolysis, the synergistic development of carbon skeleton and pore networks in a wide temperature range of 200–800 °C was unraveled. The relative abundance of aromatic carbon structures increased exponentially with increasing temperature, as determined by 13 C NMR deconvolution. Additionally, the g-factor type of radicals changed from O-centered (g-factor <2.0030) to C-centered (g-factor >2.0040) radicals. The evolution of the char macromolecules structure from disorder to order was principally characterized by a decrease in aromatic spacing ( d 002 , 3.36→3.37 Å) an d an increase in stacking degree ( L c , 7.89→8.67 Å) and aromaticity ( f a , 75.19%→96.94%). f a h a s a strong negative linear correlation with d 002 ( R 2 = 0.965). Ternary quadratic polynomials can relate specific surface area, total pore volume, and relative carbon content to the pore fractal dimension. The hypothesized chemical reaction networks and synergistic development of carbon skeleton and pore networks are essential for lignin effective valorization by a pyrolysis-based biorefinery strategies.
研究领域:
生物质能
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Xingxin Niu,Chengdeng Wang,Wenyuan Zhang,Donghua Wang,Haofeng Shi,Lu Yu,Chong Wang,Zhihao Xiong,Zhen Ji,Yan Gao,Xiaoqin Yan
The application of silicon-based anode remains a serious challenge due to its intrinsic volumetric expansion effect and low conductivity. In our work, a novel CNT-interspersed hierarchical carbon shell structure (denoted as PDA@CoZn-NC@Si) is synthesized by wrapping Si uniformly in the bimetallic zeolite imidazolate frameworks (ZIFs) and then encapsulated with a dopamine-derived carbon shell. The PDA@CoZn-NC@Si anode delivers better cycle stability of 814 mAh/g at 0.5C for 400 cycles (only −0.14% capacity reduction per cycle) and possesses excellent rate capability, which benefits from the inner porous buffer spaces, interspersed CNT, and solid heterogeneous carbon shells. In addition, the full cell is assembled by pairing a solution-based chemically prelithiated PDA@CoZn-NC@Si anode with a Li(Ni 1/3 Co 1/3 Mn 1/3 )O 2 (NCM111) cathode, and it presents an improved initial coulombic efficiency (88.3%) and a high energy density (419.8 Wh/kg). This study provides effective guidance for optimizing the microstructure design and prelithium of Si-based anodes.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2023
·
IF 7.4
Yitao Lv,Yi Zhang,Yunyin Yang,Jingyan Li,Jiacheng Wang,Xilin Xiao,Min Zhang
Specific and sensitive sensing of most pesticide residues relies on enzymes such as acetylcholinesterase and advanced materials, which need to be loaded on the surface of working electrodes, leading to instability, uneven surface, tedious process, and high cost. Meanwhile, employing certain potential or current in electrolyte solution could also modify the surface in situ and overcome these drawbacks. However, this method is only regarded as electrochemical activation widely applied in the pretreatment of electrodes. In this paper, by means of regulating the electrochemical technique and its parameters, we prepared a proper sensing interface and derivatized the carbaryl (a carbamate pesticide) hydrolyzed form (1-naphthol) to enhance sensing by 100 times within several minutes. After regulation I by chronopotentiometry with 0.2 mA for 20 s or chronoamperometry with 2 V for 10 s, abundant oxygen-containing groups form and the ordered carbon structure is destroyed. Sweeping from −0.5 to 0.9 V through cyclic voltammetry for only one segment, following regulation II, the composition of oxygen-containing groups changes and the disordered structure is alleviated. Finally, on the constructed sensing interface, test by regulation III through differential pulse voltammetry from 0.8 to −0.4 V, resulting in derivatization of 1-naphthol during 0.8–0 V, followed by electroreduction of the derivative at around −0.17 V. Compared with the electro-oxidation peak at 0.5 V in previous reports, it is essential to improve specificity, even toward several other carbamate pesticides with similar structures. Hence, the in situ electrochemical regulation strategy has demonstrated great potential for effective sensing of electroactive molecules.
研究领域:
分析化学
·
环境科学
·
农药检测
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Hong Liu,Manfang Chen,Peng Zeng,Xiaolong Li,Jing Luo,Yongfang Li,Ting Xing,Baobao Chang,Xianyou Wang,Zhigao Luo
Lithium sulfide (Li2S)-oriented cathodes of lithium–sulfur batteries (LSBs) are intensively studied in virtue of their high energy density, outstanding charge/discharge characteristics, and safety. In this study, Li2S is embedded in a three-dimensional (3D) micro-/mesoporous carbon architecture with a tunable internal structure, low density, suitable void volume, and pore size via carbonization. The mesoporous internal structure can offer considerable voids for volume change and a fast transfer route of charges and ions, and the microporous coating layer could physically block the shuttle of polysulfides and accommodate the diffusion of Li+ ions. The results show that the as-fabricated Li2S/CMK3/C has a high lithium sulfide loading of 79 wt %. At the same time, the battery delivers a high specific capacity of 848 mA h g–1 at 0.1 C and a good capability of 410 mA h g–1 after 400 cycles at 2 C. Therefore, the Li2S-embedded 3D micro-/mesoporous carbon architecture could be a significant option for the development and industrialization of high-performance LSBs.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Meng Hu,Jiwei Pang,Yuan Tang,Mengdong Ma,Junwen Huang,Penghui Li,Lu Shi,Yan Zhong,Julong He,Jianning Ding
Amorphous carbon exhibits superior performance over its crystalline counterparts due to its unique structural configuration characterized by short-to-medium-range ordered and long-range disordered structure, which fundamentally expands its potential applications in advanced technological fields. The exploration and preparation of novel bulk amorphous carbon materials through innovative synthesis approaches remain crucial in materials research. Here, we successfully synthesized bulk amorphous carbons composed of onion-like carbon structures embedded in disordered graphene networks prepared via spark plasma sintering of carbon black at a pressure of 50 MPa and temperatures ranging from 1700 to 2200 °C. The bulk amorphous carbon demonstrates a unique combination of low density and exceptional mechanical and electrical properties. The sample synthesized at 2200 °C exhibits superior mechanical properties with nanoindentation hardness of 603 MPa, Young’s modulus of 6.78 GPa, compressive strength of 169 MPa, and flexural strength of 69 MPa, comparable to the commercial ISO-68 graphite from Toyo Tanso Co., Ltd. In addition, this bulk amorphous carbon exhibits excellent electrical conductivity, reaching 9.3 × 103 S/m at room temperature. This type of bulk amorphous carbon demonstrates particular promise for advanced applications in aerospace engineering, energy storage, electronic devices, and precision machinery manufacturing.
研究领域:
材料科学
·
纳米技术
·
工程学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）