ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Yunfei Yao,Zhiying He,Xiangyang Xu,Yuanlin Tong,Dongsheng Chen,Chenyu Huang,Hongye Zhao
Following a flowsheet comprised of a hydrothermal reaction and a dehydration/carbonization, Si-xFe/O@C anodes featured with Fe-doping and carbon encapsulation were assembled. Comparing with pure Si, Si disseminated with in situ generated nano-scaled ferric oxide (Fe 2 O 3 ) particulates displays remarkably improved cyclic performance. Fe 2 O 3 may induce amorphization and optimize electrical conductivity, by enhancing the formation of Fe and Li 2 O amidst charging-discharging cycles. The as-derived Fe phase benefits the transport and storage of lithium-ion and electrons. Meanwhile, numerous tiny interfaces can be constructed between Fe granules and adjacent Li x Si or Li 2 O, and generate pseudocapacitance. After the carbonization of resorcinol-formaldehyde resin encapsulated on Si granules, core-shell structured Si- x Fe/O@C particulates can be assembled. Owing to the synergism of defect-rich structure, carbon layer well-wrapped thereon and interfacial pseudocapacitance, these nanocomposite anode materials exhibit long cyclic and upgraded rate performance. After 200 cycles, Si-0.42Fe/O@C anode retains a capacity of 929 mAh·g −1 at 1 A·g −1 and 735 mAh·g −1 at 2 A·g −1 . In the rate performance test operated at 5 A·g −1 , a high current density, 844 mAh·g −1 could be released. Si-0.42Fe/O@C can be charged with a specific capacity exceeding 250 mAh·g −1 over the potential range of 0.75-3 V at various current densities, demonstrating the contribution of nano-Fe pseudocapacitance effect to the energy storage of Si 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
Journal of the American Chemical Society
·
2023
·
IF 15
Zhi-Zheng Wu,Xiao-Long Zhang,Peng-Peng Yang,Zhuang-Zhuang Niu,Fei-Yue Gao,Yu-Cai Zhang,Li-Ping Chi,Shu-Ping Sun,Jing-Wen DuanMu,Pu-Gan Lu,Ye-Cheng Li,Min-Rui Gao
Carbon–carbon coupling electrochemistry on a conventional copper (Cu) catalyst still undergoes low selectivity among many different multicarbon (C2+) chemicals, posing a grand challenge to achieve a single C2+ product. Here, we demonstrate a laser irradiation synthesis of a gerhardtite mineral, Cu2(OH)3NO3, as a catalyst precursor to make a Cu catalyst with abundant stacking faults under reducing conditions. Such structural perturbation modulates electronic microenvironments of Cu, leading to improved d-electron back-donation to the antibonding orbital of *CO intermediates and thus strengthening *CO adsorption. With increased *CO coverage on the defect-rich Cu, we report an acetate selectivity of 56 ± 2% (compared to 31 ± 1% for conventional Cu) and a partial current density of 222 ± 7 mA per square centimeter in CO electroreduction. When run at 400 mA per square centimeter for 40 h in a flow reactor, this catalyst produces 68.3 mmol of acetate throughout. This work highlights the value of a Cu-containing mineral phase in accessing suitable structures for improved selectivity to a single desired C2+ product.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Yuling Ma,Airong Li,Cheng Wang,Xingbo Ge
Phosphotungstic acid (H 3 PW 12 O 40 , HPW) exhibits a good desulfurization performance towards the oxidative desulfurization (ODS) of oil-derived fuels. However, it presents two drawbacks: a small specific surface area and poor recovery. In this work, HPW was loaded on the support UiO-66 with a stable structure and large specific surface area, and a family of HPW@UiO-66 catalysts was prepared. Based on the structure and property analyses of powder FT-IR, ICP-OES, XRD, SEM, TG and BET, 0.5-HPW@UiO-66 with defects possessed a high crystallinity, regular morphology, stable structure and dispersed HPW clusters. The removal efficiency of DBT reached 100% and was maintained at 94.70% after 12 times of repeated use under the optimal reaction conditions. The results showed that the catalytic performance of HPW@UiO-66 catalyst for model oil desulfurization was improved when the defects existed.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2025
·
IF 7.2
Guoqing Jiao,Xuan Liu,Honglong Hu,Conglong Yuan,Zhi-Gang Zheng
The molecular ordering and defects in self-assembled soft matter systems are pivotal to their functionality and the advancement of innovative applications. However, achieving precise guidance in the assembly and dynamical modulation of defect structures in an artificial manner remains a formidable challenge in soft matter and interdisciplinary science. Herein, a digitally controlled pixelated holographic lithography system is established to fabricate nanoscale surface reliefs, enabling precise manipulation of smectic liquid crystal lamellar defect structures. These surface reliefs, with customizable topographic features, facilitate versatile smectic soft defect engineering, allowing selective assembly of square focal conic domains and oily streak defects, along with precise control over their periodicity, orientations, and patterned coexistence within micro-regions. The defect structures demonstrate exceptional stability and durability under UV irradiation, providing a robust framework for versatile defect engineering. This work opens a new pathway for manipulating lamellar superstructures in soft matter, offering potential applications in advanced functional materials and devices.
研究领域:
材料科学
·
物理化学
·
软凝聚态物理
✓ 已验证
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Jieqi Chen,Haiyan Zhang,Bingbing Li,Xiaolin li,Jingxun Chen,Meng Ning,Zhenghui Li
Carbon is one of the most superior anode materials for K-ion batteries but faces the challenges of low capacity and poor cycle stability. In general, the K + storage capacity depends on the graphitized carbon layers and defective structure, while the cycle stability can be enhanced by constructing sufficient nanospace to alleviate the volume expansion during the potassiation/depotassiation process. However, the above structures are difficult to integrate into a single carbon material because graphitization often eliminates defects and pore structures. In this work, we find that ultrathin carbon sheets have a confined graphitization effect, which allows the carbon layer to orientationally arrange at a low heating-treatment temperature. More importantly, this orientational arrangement causes size shrinkage, inducing structural splitting on the faces of the carbon sheets and producing abundant defects and a large number of pores. Based on this, we obtain a novel carbon with highly graphitized, large-surface-area and defect-rich frameworks, which gives a K + storage capacity of 358 mAh g −1 , and after 4000 cycles, this carbon shows no obvious capacity degradation, with a capacity retention rate of nearly 100 %. Carbon anodes of K-ion batteries with such large capacity and long cycling life have rarely been achieved before.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Small Structures
·
2025
·
IF 11.3
Ibrahim Abdalla,Ahmed Elhassan,Salma Ali,Malik Yonis Hassan Saty,Ekrema Adam,Lihua Zou,Qingqing Ni,Zhenzhen Xu
Carbon nanofibers (CNFs) exhibit inherent dielectric properties that enhance electromagnetic (EM) wave absorption, yet challenges exist in expanding their effective absorption bandwidth (EAB) and improving flexibility. Many studies fail to adequately consider how structural factors influence performance when combining CNFs with magnetic materials. To address these issues, a 1D carbon nanocomposite is developed by embedding magnetic oxide nanoparticles within CNFs using a simple electrospinning technique. This approach improves membrane flexibility by disrupting rigid alignment and introducing dynamic magnetic interactions, while also creating defect-rich interfaces that increase the amorphous content (61%) of the CNFsF composite, leading to improved EM wave absorption. The unique macro/mesoporous morphology provides internal interfaces and heterogeneous boundaries that effectively trap and dissipate EM waves. As a result, the flexible CNF composites demonstrate significant EM wave absorption performance, achieving a minimum reflection loss (RL min ) of −39.8 dB at 4.64 GHz and an abroad EAB of up to 7 GHz at only 2.5 mm thickness. Computer simulation technology (CST) simulations indicate a maximum radar cross-section reduction of 21.1 dB m 2 , highlighting the material's radar stealth capability. This research advances the development of high-performance materials and offers new strategies for enhancing absorption properties through composite engineering.
研究领域:
材料科学
·
电磁学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
Applied Materials Today
·
2021
·
IF 10.041
Rencheng Zhuang,Dekai Zhou,Xiaocong Chang,Yi Mo,Guangyu Zhang,Longqiu Li
Design and synthesis of electric-driven micro/nanomotors (EDMNMs) have attracted tremendous attention because of their unique advantages, such as non-necessity of fuel, high mobility, and flexible controllability. However, existing EDMNMs are mostly Janus structures based on two hemispheres made from heterogeneous materials . Here, we propose a new type of defective electric-driven micro/nanomotor with an asymmetric shape. It is found, for the first time, that the defective golden micro/nanomotors (DGMs) can generate a locally asymmetric field gradient through the topological defect, and can achieve controllable self-dielectrophoresis (sDEP) and induced-charge electrophoresis (ICEP) motion behaviors in different frequency ranges. In particular, the DGMs can achieve three-dimensional helical motion behavior through designing their defective structure. Furthermore, we demonstrate that the DGMs can attract or repel cargos under different electric frequencies. These new DGMs and their attractive performance pave the way for fabricating highly controllable EDMNMs via structural design and can be widely applied in biomedicine, micro/nanosensors, and micro/nanomechanical systems.
研究领域:
材料科学
·
生物医学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2018
·Vol. 29
·期 2
·1806300
·
IF 13.325
Kai Liu,Wei Wang,Penghui Guo,Jinyu Ye,Yuanyuan Wang,Pingting Li,Zixi Lyu,Yongsheng Geng,Maochang Liu,Shuifen Xie
Metal nanostructures with an ultrathin Pt skin and abundant surface defects are attractive for electrocatalytic applications owing to the increased utilization efficiency of Pt atoms and the presence of highly reactive sites. This paper reports a conformal, layer-by-layer deposition of Pt atoms on defective Rh nanowires for the faithful replication of surface defects (i.e., grain boundaries) on the Rh nanowires. The thickness of the Pt shell can be controlled from one monolayer up to 5.3 atomic layers. This series of Rh@Pt n L ( n = 1–5.3) core–sheath nanowires show greatly enhanced activity and durability in catalyzing the ethanol oxidation reaction in an acidic medium. Among others, the Rh @ Pt 3.5L nanowires show the greatest mass activity (809 mA mg −1 Pt ) and specific activity (1.18 mA cm −2 ) after loaded on carbon support, which are 3.7 and 3.4 times those of the commercial Pt/C, respectively. In situ Fourier transform infrared spectroscopy studies indicate an enhanced interaction between the outermost Pt layer and the Rh nanowire can promote C C bond cleavage for complete oxidation of ethanol to CO 2 while depress the dehydrogenation of ethanol to acetic acid. As the Pt shell thickness is increased, the selectivity for the CO 2 pathway decreases while that for acetic acid is increased.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2018
·Vol. 14
·期 39
·1802694
·
IF 9.598
Haiyan Lu,Fangxing Ai,Yanlong Jia,Chunyan Tang,Xinhe Zhang,Yunhui Huang,Hanxi Yang,Yuliang Cao
Hard carbon is considered as one of the most promising anodes in sodium-ion batteries due to its high capacity, low cost, and abundant resources. However, the available capacity and low initial Coulombic efficiency (ICE) limits the practical application of hard carbon anode. This issue results from the unclear understanding of the Na + storage mechanism in hard carbon. In this work, a series of hard carbons with different microstructures are synthesized through an “up to down” approach by using a simple ball-milling method to illustrate the sodium-ion storage mechanism. The results demonstrate that ball-milled hard carbon with more defects and smaller microcrystalline size shows less low-potential-plateau capacity and lower ICE, which provides further evidence to the “adsorption–insertion” mechanism. This work might give a new perspective to design hard carbon material with a proper structure for efficient sodium-ion storage to develop high-performance sodium-ion batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2022
·
IF 10.319
Yameng Jiao,Qiang Song,Xuemin Yin,Liyuan Han,Wei Li,Hejun Li
Due to the limited electromagnetic wave (EMW) loss capacity and agglomeration, carbon black (CB) gradually fails to meet the increasingly harsh demanding conditions. Herein, defect-rich bamboo-like carbon nanotubes (CNTs) were grown on CB by the process of chemical vapor deposition . CNTs prepared in situ on CB can assist it to build a developed multilevel conductive network and introduce plentiful CB/CNTs nano-interfaces. What's more, the defects that accompany the growth of CNTs endow CNTs with a moderate conductivity and good impedance matching, thereby causing an effective microwave absorption (MA). Meanwhile, the high-density defects on CNTs can induce dipole polarization to further strengthen the EMW loss ability. The influence of CNTs with different growth time on MA performance has been explored. Profiting from the structural merits, the synthesized CB-CNT with CNTs growth time of 40 min exhibits the optimal absorbing property, which has the minimum reflection loss of -53.6 dB and maximum effective absorption bandwidth of 4.1 GHz with the thickness of 2.7 mm, covering almost the entire X band. The introduction of defect-rich CNTs significantly enhances the EMW loss ability of CB, which provides a rational strategy for the design of high-efficient microwave absorption materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Menghan Qin,Yumiao Shi,Dingkun Lu,Jingjing Deng,Guoyue Shi,Tianshu Zhou
Due to the excessive use, cephalosporin antibiotics have been detected in various aquatic environments, which may result in environmental and health concern. In this study, bimetallic metal–organic frameworks (MOFs), Hf-UiO-66 and Ti-UiO-66, were successfully designed and obtained via post-synthetic method from UiO-66 for the adsorption of cefoperazone. A serious of adsorption experiments were investigated. The adsorption kinetics and isotherms demonstrated that the adsorption process followed pseudo-second-order kinetic model and Langmuir isotherm model. Hf/Ti-UiO-66 exhibited much better adsorption performance than the undoped UiO-66. Particularly, Hf-UiO-66 had the highest adsorption capacity (346.0 mg g −1 ). With the introduction of Hf or Ti, the chemical coordination environment changed, which resulted in defective structures of MOFs. Such defective structures increased the adsorption active sites, changed the surface charges and enlarged pores. Based on the characterization by FT-IR, XPS, and zeta potential, it was identified that the electrostatic attraction, π-π stacking, hydrogen bonding and metal complexation were the driving force for the high adsorption capacity of the bimetallic MOFs. The as-prepared MOFs displayed good stability and reusability. This work provides a great prospect for the design and application of bimetallic defective MOFs in cephalosporins removal in environmental water.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the American Chemical Society
·
2022
·
IF 16.383
Xiaodong Yang,Bo Ouyang,Peiqi Shen,Yiqiang Sun,Yisong Yang,Yanan Gao,Erjun Kan,Cuncheng Li,Kun Xu,Yi Xie
Developing efficient hydrogen oxidation reaction (HOR) electrocatalysts in alkaline media is of great significance for anion exchange membrane fuel cells. Herein, we report the synthesis of hollow colloidosomes composed of Ru nanocrystals based on a novel gas/liquid interface self-assembly strategy. Structural characterizations reveal that much defects are present in the building block (Ru nanocrystals) of Ru colloidosomes. Theoretical calculations suggest that the defects in the Ru structure can optimize the adsorption binding energy of reaction intermediates for the HOR. Benefiting from the assembled colloidosome and optimized electronic structure, the Ru colloidosomes exhibit remarkable HOR catalytic performance in alkaline media with a mass activity higher than that of benchmark Pt/C. Our work may shed new light on the rational design of advanced electrocatalysts with an assembled structure for energy-related applications.
研究领域:
材料科学
·
电化学
✓ 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）