ADVANCED MATERIALS
·
2025
·
IF 26.8
Yue Pan,Xiaohong Yuan,Yong Cheng,Baoyin Xu,Shucheng Liu,Zhitong Wang,Shida Wang,Kuo Hu,Shengcai Zhu,Quanjun Li,Ming-sheng Wang,Zhaodong Liu,Hu Tang,Bingbing Liu
Synthesizing fully sp 3 -bonded non-crystalline carbon remains a long-standing challenge due to the intrinsic instability of the sp 3 bond at ambient pressure. Recently, paracrystalline diamond, a new-form sp 3 -bonded non-crystalline carbon consisting of sub-nanometer-sized paracrystallites, has been synthesized from face-centered cubic C 60 at 30 GPa, which has attracted attention due to its unique structural features and excellent physical properties. However, the ultrahigh synthesis pressure of paracrystalline diamond poses an obstacle to its large-scale production and applications. In this study, paracrystalline diamond is synthesized at an exceptionally low pressure (16 GPa) via inducing uniaxiality at high-pressure and high-temperature conditions, thereby breaking through the temperature-pressure phase diagram of C 60 . By combining structural characteristics and advanced molecular dynamics simulation, the remarkable reduction of synthesis pressure is attributed to the fact that the symmetry of the C 60 cage is broken due to the uniaxiality, which further allows the C 60 cage to collapse at much lower pressures. This work reveals the critical role of uniaxiality in the reduced-pressure synthesis of paracrystalline diamond, which may provide a potent methodological strategy for the development of novel low-cost high-pressure materials.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2023
·Vol. 58
·期 22
·9382-9393
·
IF 4.5
Wang Bingying,Zhang Keke,Gao Yijie,Liu Peng,Liu Bo,Zhang Zhansheng
The trend toward miniaturized and highly integrated chip packaging has created a pressing need for lead-free solders with high strength, toughness, and conductivity. In this paper, we designed a scheme of Al 2 O 3 -modified nanomaterial-reinforced low silver Sn1.0Ag0.5Cu (SAC105) solder matrix. To begin with, a novel amorphous carbon and nickel core–shell structure plating modified on Al 2 O 3 (C/Ni/Al 2 O 3 ) were prepared by the electroless plating method. Then, the nano-C/Ni/Al 2 O 3 particle as reinforcement phase was mixed into the matrix solder alloy by ultrasonic vibration stirring. Finally, the morphology and relationship between coated carbon, deposited nickel and original solder interface were analyzed. The microstructure and main properties of the modified solders were also investigated. The experimental results suggested that amorphous carbon and nickel film were prepared on the surface of Al 2 O 3 by electroless plating method. The outer layer of nano-Al 2 O 3 was coated with non-uniform thickness of nickel and carbon coatings. The mass percentage of amorphous carbon was about 3.50%. Adding C/Ni/Al 2 O 3 (0–0.5%) into the SAC105 solder matrix resulted in a gradual increase in conductivity and wettability. The strength and toughness of the modified solder alloy improved as well with the adjunction of reinforced phase. The tensile fracture surface exhibited from a mixture of ductile and brittle, characterized by dimples and cleavage surface, to a purely ductile mode consisting mainly of dimples.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Xiao Sun,Chuanbing Cheng,Jianxing Shen,Yang Liu,Tailin Wang,Qian Ma,Runhua Fan
In this work, amorphous carbon/alumina (C/Al 2 O 3 ) metacomposites with tunable negative permittivity were synthesized by a facile impregnation method. We analyzed the influence of carbon content and the carbonization temperature on the microstructure and electrical properties of the metacomposites. It was found that the conductive carbon networks were formed in the composites with the higher carbon contents and carbonization temperatures, which lead to the appearance of a metal-like conduction and negative permittivity behavior. Low-frequency plasmonic state provided by plenty of free electrons in the carbon networks resulted in the negative permittivity, and its numerical values could be effectively adjusted by controlling the carbon content and carbonization temperature, which could be well explained by Drude model. This work provides a feasible way to prepare metacomposites with tunable negative permittivity, which will expand their potential applications in shielding, absorbing and novel capacitor fields.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2021
·
IF 9.594
Ye Fan,Chao Deng,Yuxuan Gao,Yi Ding,Yuchen Wu,Shiman Mo,Yingbang Yao,Bo Liang,Shengguo Lu,Wen Qi,Tao Tao
Using Li-carbon composites as anodes in high-energy-density lithium batteries leads to significant improvements in cycling life and safety compared with lithium metal. Li 2 C 2 consisting of dumbbell anions is the most thermodynamically stable phase in the family of lithium-carbon materials, however its low conductivity is a critical obstacle to the practical applications. sp 2 -hybridizing carbon is one promising option for unique electronic structures. Here, Li 2 C 2 alloy nanosheets composed of sp 2 -hybridized carbon atoms are directly formed from Li element and carbon during ball milling process, presenting a metallic feature at ambient conditions. After removing lithium from these alloy nanosheets, amorphous carbon ultrathin nanosheets are obtained. A vertically aligned Li 2 C 2 nanosheet foil prepared by pressing the milled powder, can be used as free-standing, binder-free electrodes for fabricating various types of lithium batteries, and their excellent electrochemical performance is attributed to a highly reversible Li atoms uptake in amorphous carbon nanosheets.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
iScience
·
2024
·
IF 4.6
Binxia Yuan,Yuhao Liu,Hong Qian,Rui Zhu,Chengxi Zhang,Weiling Luan
In this study, the theoretical calculations proves that the combination of oxygen vacancy and amorphous carbon films in TiO 2 (V O -CT) can effectively reduce the energy bandgap and work function. The minimum Gibbs free energies required for the CO 2 RR reaction of V O -CT are 0.20 eV, which is lower than pure TiO 2 . The amorphous c@TiO 2 nanomaterials with oxygen vacancy and mesoporous structures (V O -MCT) are prepared with the P123 surfactant as the template and oxalic acid as an inducer. The electron paramagnetic resonance indicates the presence of abundant oxygen vacancy defects in the samples. UV-vis spectra indicate that the mesoporous structure enhances light absorption capacity. The photocatalytic CO 2 reduction tests show that the highest conversion rates for CH 4 and CO of V O -MCT are 14 μmol g −1 h −1 and 10.66 μmol g −1 h −1 , respectively. The electron consumption rate of V O -MCT is 12.43 times higher than that of commercial TiO 2 (P200).
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBON
·
2019
·
IF 7.466
Jinzhu Tang,Shuqing Chen,Yulong Jia,Ying Ma,Hongmei Xie,Xin Quan,Qi Ding
As a new type of carbon material, carbon dots (CDs) with exceptional properties are regarded as a type of potential water-based lubricant additive . In this study, it is first demonstrated that CDs perform excellently when used as lubricant additives for water-lubricated amorphous carbon (a-C) contacts. The results show that the introduction of CDs into water at a concentration of 0.1 wt% could reduce friction and wear in a-C contacts by 33% and 80%, respectively. Additionally, the lubricating performance of CDs is highly sensitive to its adding concentration. The excellent tribological performance of CDs results from the minimized CDs sediment particles (deposited in situ on worn a-C surfaces) and the reduced friction and wear via nano-bearing and nano-filling mechanisms. With high CDs concentrations, however, micron and submicron-sized sediment particles form when friction occurs and cause undesirable abrasive wear . For water-lubricated a-C contacts, therefore, the CDs concentration is the crucial determinant of lubrication performance that has to be appropriately controlled.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2017
·
IF 6.337
Shanshan Xiao,Hui Mei,Daoyang Han,Konstantinos G. Dassios,Laifei Cheng
Three-dimensional hybrid foams of SiC nanowires (SiC NWs) coated and bonded with nanostructured lamellar carbon films are, herein synthesized for the first time, by combination of unidirectional freeze drying and carbonization techniques. The crystallinity of the carbon films was tunable from amorphous carbon to graphene-like carbon by heat treatment of the as-received hybrid foams to different temperatures within the range of 600–1500 °C. The SiC NWs-nanostructured lamellar carbon (SiC NWs/C) hybrid foams exhibited electromagnetic (EM) wave absorbing properties highly superior to current state-of-the-art counterparts, at filler loadings as low as 9.2 mg/cm 3 . Effective absorption bandwidth of the SiC NWs/C foam was observed to cover the whole X-band frequency range of 8.2–12.4 GHz, with reflection loss values reaching −31 dB for an optimum thickness of 3.3 mm. The absorption efficiency of the SiC NW/C hybrid foams is discussed in the text in view of the highly absorbing layered morphology of the developed material, of interfacial polarization and multiple reflections effects and of polarization relaxation effects.
研究领域:
材料科学
·
电磁学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Qi Huang,Yao Cong,Zijie Xu
Designing controllable multilayer graphene (MLG) structure in amorphous carbons is crucial but still challenging to deliver durable supercapacitive energy storage. Herein, the lead is taken in in-situ nanoarchitecturing a 2–10 layered graphene structure within the amorphous carbon skeleton by the cobalt salt/sodium metal-assisted carbonization of starch. The rearrangement of graphite crystallites forms MLG structure, which shows a large specific surface area of 1917 m 2 g −1 and a mesopore volume of 0.71 cm 3 g −1 . These two parameters are 1.64 and 1.46 times of the corresponding amorphous carbon. Such profitable structures promise a high specific capacitance of 312 F g −1 at 1 A g −1 and a durable cycle-life with 98.5% capacitance retention at 10 A g −1 over 100,000 cycles. The designed MLG structure in amorphous carbons matrix also exhibits an increased electrochemically active surface area from 392.5 to 599.5 m 2 g −1 , and a low ion-transport resistance (0.59 Ω s –0.5 ) as well as an ultrafast ion-response time (0.37 s), endowing the fabricated carbon supercapacitor with 67.7% capacitive contribution from fast-kinetics response at 10 mV s –1 . Experiment characterization unravels the formation mechanism of MLG in amorphous carbons via the synergy of coalt salt and sodium metal. The elaborate design of MLG structure within amorphous carbon matrix provides an effective strategy to boost the electrochemical energy storage performances.
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 COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Yuning Shi,Xueai Li,Jinjin Yang,Kexin Jin,Wanchun Guo,Kesong Tian,Chunsheng Wang,Yahui Wang,Haiyan Wang
Carbon derived from polymers as microwave absorbing materials (MAMs) has been extensively explored owing to amelioration of balance between impedance matching and dielectric loss by strategies of morphology, nano-microstructure and intrinsic structure. Nevertheless, it is difficult to discern contribution between ohmic loss and polarization relaxation on microwave attenuation due to lack of methods to control the electrical conductivity at a certain value with distinct dipole polarization. Herein, pseudo-graphite proportion in amorphous carbon was controlled by the degree of polymerization of the precursor that was determined by the oligomerization reaction rate. The close electrical conductivities of amorphous carbon with an appropriate range of pseudo-graphite proportion provided a guarantee for impedance matching while avoiding the disparate effects of ohmic loss, thus, the synthetic amorphous carbon with a controllable pseudo-graphite proportion can be used to investigate the impact of polarization loss on the dissipation of microwave. The relative lower pseudo-graphite proportion within limits provided abundance of defects, provoking dipole polarization loss to achieve enhancement of microwave attenuation. The synthetic amorphous carbon with an appropriate proportion of pseudo-graphite phase exhibited excellent microwave absorption with an effective absorption bandwidth (EAB) of 6.64 GHz at a thickness of 2.2 mm over the whole Ku band. This work provided an efficient method to research the contribution of dipole polarization on electromagnetic response and found an effective direction to achieve broad bandwidth response at low thickness for carbon MAMs.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2016
·Vol. 9
·期 10
·795
·
IF 2.728
Jinzhu Tang,Qi Ding,Songwei Zhang,Guizhi Wu,Litian Hu
Nanomaterials, such as Graphene, h-BN nanoparticles and MoS2nanotubes, have shown their ability in improving the tribological performance of amorphous carbon (a-C) coatings. In the current study, the effectiveness of ZrO2nanoparticles (ZrO2-NPs) in lubricating the self-mated nonhydrogenated a-C contacts was investigated in boundary lubrication regime. The results showed that 13% less friction and 50% less wear compared to the base oil were achieved by employing ZrO2-NPs in the base oil in self-mated a-C contacts. Via analyzing the ZrO2-NPs and the worn a-C surface after tests, it was found that the improved lubrication by ZrO2-NPs was based on “polishing effects”, which is a new phenomenon observed between a-C and nanoparticles. Under the “polishing effect”, micro-plateaus with extremely smooth surface and uniform height were produced on the analyzed a-C surface. The resulting topography of the a-C coating is suitable for ZrO2-NPs to act as nano-bearings between rubbing surfaces. Especially, the ZrO2-NPs exhibited excellent mechanical and chemical stability, even under the severe service condition, suggesting that the combination of nonhydrogenated a-C coating with ZrO2-NPs is an effective, long lasting and environment-friendly lubrication solution.Keywords:amorphous carbon coating;ZrO2nanoparticles;friction coefficient;wear;polishing effect
研究领域:
材料科学
·
摩擦学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
Hongquan Liu,Pengxin Duan,Zhenguo Wu,Yuao Liu,Zhengjuan Yan,Yanjun Zhong,Ye Wang,Xinlong Wang
Silicon has emerged as one of the most promising anode materials for next-generation lithium-ion batteries due to its exceptional specific capacity and abundant resources. However, its widespread application is hindered by structural deformability and low intrinsic conductivity. By strategically integrating a conductive carbon matrix with silicon, it becomes feasible and efficient to enhance the electrical conductivity of silicon and accommodate the stress-induced volume expansion during battery operation. In this study, a series of silicon/graphite/amorphous carbon (Si/G/C) composites were prepared using mechanical milling and carbothermal reduction. The study focused on two main aspects: the effect of the ratio of micro-sized silicon to flake graphite on the properties of the composite and the compatibility of different-scale silicon particles (micro-sized silicon and nano-sized silicon) and different kinds of natural graphite (flake graphite and cryptocrystalline graphite). The results reveal that when micro-sized silicon and flake graphite are combined, the graphite is fragmented more thoroughly, resulting in smoother surfaces and reduced aggregation of secondary particles. The composites with a mass ratio of 7:3 micro-sized silicon to flake graphite have the smallest specific surface area and pore size, homogeneous distribution, and stable structure. This exceptional carbon-to-silicon ratio endows the Si/G/C composite with rapid reaction kinetics, enabling a specific discharge capacity of 854.1 mAh g -1 after 200 cycles at 1A g -1 . The findings offer valuable insights into the design and optimization of silicon-based anode materials for next-generation lithium-ion batteries.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2021
·
IF 5.876
Xu Tian,Mengqi Xue,Xiaonan Yang,Daochuan Jiang,Yupeng Yuan
Background Up-cycling of waste papers to value-added carbon products has significant environmental and economic benefits in real life. This work aims to recycle the waste papers to construct amorphous carbon modified graphitic carbon nitride composite photocatalysts for efficient photocatalytic hydrogen generation from water under visible light. Methods Amorphous carbon (labeled as a-C) was yielded from the office waste papers by simple sulphuric-acid treatment and then combined with graphitic carbon nitride (g-CN) to form the g-CN/a-C composite photocatalysts by the thermolysis of a-C and melamine mixture. Significant Findings The addition of a-C enlarges the surface area of g-CN from 11.52 m 2 g −1 of pristine g-CN to 28.12 m 2 g −1 of g-CN/a-C-100. In addition, the a-C incorporation can significantly separate the electrons from the photoexcited g-CN owing to the excellent conductivity of a-C. As a result, an increased photocatalytic H 2 generation was realized under visible light exposure. The g-CN/a-C-100 sample with optimized a-C contents offers the highest photocatalytic H 2 generation rate of up to 17.1 μ mol h −1 , which is ∼12 times higher than that of pristine g-CN under the same condition. The present study manifests the great potential of the recycling of office waste papers for increased photocatalytic H 2 generation.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 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）