POLYMERS FOR ADVANCED TECHNOLOGIES
·
2018
·Vol. 29
·期 12
·2982-2991
·
IF 2.137
Zhiyong Zhang,Miaojun Xu,Bin Li
The polymethacrylimide/silicate (PMI/silicate) composites were successfully prepared from the monomers of acrylonitrile (AN) and methacrylic acid (MAA) via the monomer in situ intercalation polymerization and free foaming. The formation of imide groups was monitored by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results of FTIR and XPS indicated that the imide groups were gradually formed and cyano groups were dwindling but still existed during foaming and thermal treatment. The thermogravimetric analysis results revealed that the thermal stability of the PMI/silicate composites was improved, the rate of thermal degradation was reduced, and the residue was increased because of the addition of silicates. The results of dynamic mechanical analysis revealed that the rigidity and the glass transition temperature of the composites were improved. The limit oxygen index (LOI) and cone calorimeter (CONE) test showed that the fire-retardant properties were improved because of the barrier effect of silicates. The cell morphologies of the PMI/silicate composites were characterized by scanning electron microscopy (SEM), and the results showed that the silicate particles were distributed on the cell walls, but the cells slightly cracked. The mechanical properties were measured by tensile, flexural, and compressive strength. The mechanical strength, especially flexural strength, was significantly improved. The flexural strength of PMI/MMT, PMI/kaolin, and PMI/talc containing 8 wt% silicates was improved to 172%, 240%, and 233%.
研究领域:
高分子材料
·
复合材料科学
·
材料化学
·
防火材料
·
多孔材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yu Zhou,Wenjun Zhou,Chunhua Ni,Shenggang Yan,Liangmin Yu,Xia Li
Precursors of a nickel-based metal–organic framework, denoted Ni-MOF, and the loofah plant were prepared by the microwave method, and “tree blossom” Ni/Nitrogen doped Carbon (NC)/ Carbon (C) composites were prepared by in situ pyrolysis under an argon atmosphere. During pyrolysis, the morphology, specific surface area, porous structure and electromagnetic parameters of the Ni/NC/C composites were adjusted by adjusting the pyrolysis temperature. The maximum reflection loss of the corresponding Ni/NC/C composites can reach −63.1 dB at 13.84 GHz and a thickness of 2 mm when the pyrolysis temperature was 650 ℃ and the filling amount was 16 wt%. And the effective absorption bandwidth was 35.44 GHz when the thickness was adjusted from 1 mm to 5.5 mm within the range of 2–40 GHz. Excellent performance comes from conduction loss, dipole and interface polarization, magnetic resonance, multiple electromagnetic reflections and scattering, and equilibrium impedance matching.
研究领域:
材料科学
·
纳米复合材料
·
电磁功能材料
·
能源材料
·
环境功能材料
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2023
·
IF 13.1
Xuexia Lan,Xingyu Xiong,Jie Cui,Renzong Hu
In the past two decades, a lot of high-capacity conversion-type metal oxides have been intensively studied as alternative anode materials for Li-ion batteries with higher energy density. Unfortunately, their large voltage hysteresis (0.8–1.2 V) within reversed conversion reactions results in huge round-trip inefficiencies and thus lower energy efficiency (50%–75%) in full cells than those with graphite anodes. This remains a long-term open question and has been the most serious drawback toward application of metal oxide anodes. Here we clarify the origins of voltage hysteresis in the typical SnO 2 anode and propose a universal strategy to minimize it. With the established in situ phosphating to generate metal phosphates during reversed conversion reactions in synergy with boosted reaction kinetics by the added P and Mo, the huge voltage hysteresis of 0.9 V in SnO 2 , SnO 2 -Mo, and 0.6 V in SnO 2 -P anodes is minimized to 0.3 V in a ternary SnO 2 -Mo-P (SOMP) composite, along with stable high capacity of 936 mA h g −1 after 800 cycles. The small voltage hysteresis can remain stable even the SOMP anode operated at high current rate of 10 A g −1 and wide-range temperatures from 60 to −30 °C, resulting in a high energy efficiency of 88.5% in full cells. This effective strategy to minimize voltage hysteresis has also been demonstrated in Fe 2 O 3 , Co 3 O 4 -basded conversion-type anodes. This work provides important guidance to advance the high-capacity metal oxide anodes from laboratory to industrialization.
研究领域:
电化学
·
材料科学
·
能源存储
·
纳米材料
·
固态化学
·
电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2018
·
IF 6.759
Xiaolong Liu,Qingzhen Han,Wenbo Shi,Cheng Zhang,Erwei Li,Tingyu Zhu
In this work, ruthenium-based bimetallic catalysts of 1Ru-5 M/TiO 2 (M = Co, Ce, Fe, Mn, Cu, Ni) were prepared and evaluated in ethyl acetate oxidation. It was found that 1Ru-5Cu/TiO 2 gave the highest catalytic activity. The influence of CuO content and the preparation method on the catalytic activity was also studied. 1Ru-5Cu/TiO 2 showed great catalytic stability in the on-stream reaction test. The influence of H 2 O on the catalytic activity is presented. The bimetallic catalyst 1Ru-5Cu/TiO 2 showed better catalytic performance than the monometallic catalysts 1Ru/TiO 2 and 5Cu/TiO 2 . XRD, TEM, HAADF-STEM, H 2 -TPR, and XPS characterizations were conducted, and the synergistic effect between Ru and Cu was well presented. In situ FTIR studies were also conducted, and the reaction intermediates were revealed on the catalyst surface. The theoretical calculations suggested that ethyl acetate is more easily adsorbed on the CuO surface, while it reacts more easily on the RuO 2 surface . Accordingly, a reaction mechanism for the catalytic oxidation of ethyl acetate over a Ru-Cu bimetallic catalyst is proposed.
研究领域:
催化化学
·
环境化学
·
表面科学
·
材料化学
·
物理化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Liyuan Zhang,Shu Yang,Yuekun Lai,Hui Liu,Yiang Fan,Cao Liu,Haiying Wang,Liyuan Chai
Gaseous Hg 0 is one of the most deadly and hard-to-dispose pollutants. The oxidation of Hg 0 is a promising route, but the rational design and synthesis of highly efficient catalysts still remain grand challenges. Herein, CuO@Cu 2 O (or Cu x O) heterostructured nanoparticles uniformly monodispersing on porous carbon monolith were designed and successfully synthesized using oligo( m -phenylenediamine)-Cu 2+ complex as raw material. The Cu x O-carbon catalyst contains ∼28 wt% of Cu. Based on density functional theory calculation, the CuO@Cu 2 O junction interfaces can accelerate the Hg 0 oxidation by significantly reducing the energy barriers of reaction. Only 1 mg of the catalyst can catalyze the oxidation of more than 90 % of Hg 0 with [HCl] = 0.5 ppm, [O 2 ] = 6 vol%, T = 150 °C. The poisoning effect of either SO 2 or H 2 O on the catalysts is weak. Moreover, a long-term test confirmed that the Hg 0 oxidation rate can maintain more than 90 % even in the co-presence of SO 2 (5000 ppm) and H 2 O (10 vol%).
研究领域:
环境催化
·
材料化学
·
大气污染控制
·
纳米材料
·
表面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Wei Feng,Huirong Liu,Mingliang Zhao,Jianling Li,Feiyu Kang
The poly(ethylene oxide) based composite solid electrolyte(PEO-CSE) is an effective solution for developing high-performance solid-state lithium battery . However, the poly(ethlene oxide)(PEO) based solid-state lithium battery using 4.0 V cathode suffers from severe interfacial instability problems. In this work, we add additive lithium difluorophosphate(LiPO 2 F 2 ) into the PEO-CSE to form a stable and low resistance interphase at the cathode/electrolyte interface during charge/discharge process. The electrochemical stability window of PEO-CSE increases to ∼5.0 V. Besides, the electrochemical performance of PEO based solid-state lithium battery with LiCoO 2 as cathode is excellent. The discharge capacity of LiCoO 2 /Li cell with LiPO 2 F 2 reaches 108.5 mAh g −1 at 1.0C. In contrast, the discharge capacity that without LiPO 2 F 2 is only 60.0 mAh g −1 . Meanwhile, the PEO-CSE with LiPO 2 F 2 cell delivers stable cycle performance at 4.2 V. The capacity retention maintains 88.5% compared with 16.1%(without LiPO 2 F 2 ) after 100 cycles. Furthermore, it's still maintains 83.3% after 150 cycles. In addition, the cathode/electrolyte interface is analyzed by transmission electron microscope(TEM) and X-ray photoelectron spectroscopy(XPS). Galvanostatic intermittent titration test(GITT) is used to analyze the dynamic diffusion performance. This strategy provides a simple and effective way to improve the high voltage stability of the cathode/electrolyte interface.
研究领域:
电化学
·
材料科学
·
能源存储
·
固态电池
·
界面工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2017
·
IF 3.012
Haojie Zhu,Ke Yang,Hua Lan,Shangshu Qian,Haoxiang Yu,Lei Yan,Nengbing Long,Miao Shui,Jie Shu
In this work, Na 2 Ti 3 O 7 is fabricated as lithium storage material via one-step solid state reaction. Worked as anode material , Na 2 Ti 3 O 7 delivers a stable electrochemical performance with good lithium storage capability. Structural analyses show that Na 2 Ti 3 O 7 anode experiences slight volume change during electrochemical lithiation/delithiation process. Moreover, the reversibility of structural evolution is further demonstrated by in-situ X-ray diffraction technique . All these evidences prove the cycling stability of Na 2 Ti 3 O 7 as lithium storage material. Besides, the kinetic properties of the Li + ion storage in Na 2 Ti 3 O 7 are systematically investigated. The observed results reveal that Na 2 Ti 3 O 7 delivers the lithium ions diffusion coefficient in the range of 10 − 14 –10 − 12 cm 2 s − 1 during the discharge process and 10 − 15 –10 − 12 cm 2 s − 1 during the recharge process. It suggests that Na 2 Ti 3 O 7 has good lithiation/delithiation kinetics in rechargeable batteries.
研究领域:
电化学
·
材料科学
·
能源存储
·
无机化学
·
固体化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Jiajie Yu,Muzhong Shen,Siyu Liu,Feng Li,Dongping Sun,Tianhe Wang
In this paper, we describe a simple technique for direct growth of gold nanoparticles (GNPs) into a nanostructured porous alumina layer on conductive glass slide (PAOCG). PAOCG was attached firmly with a small piece of steel and was then immersed in a HAuCl 4 solution. Electro-induced electrons from steel were employed to reduce AuCl 4 − on PAOCG. The galvanic replacement reaction (GRR) was adopted as the fundamental mechanism for reducing metal precursors. This mechanism was further studied by open circuit potential-time (OCP-t) experiment and the result demonstrated that steel induced the continuous proceeding of this reaction. This strategy presents a simple and general protocol for preparation of metal nanoparticles (MNPs) on conductive glass substrates. The SERS properties of Au/PAOCG were investigated using aqueous crystal violet (CV) and 4-mercaptopyridine (4-Mpy) as probe molecules. Au/PAOCG allowed as low as 10 −9 M CV and 10 −8 M 4-Mpy to be detected. The reusability of this substrate was achieved by measuring the SERS spectrum of the probe molecules followed with a 400 °C heat treatment for 10 min to remove the residuals. This substrate could be reused for at least ten cycles without any significantly reduced SERS performance. Therefore, this surface can serve as a portable, durable and reusable SERS substrate and has a potential for commercial applications.
研究领域:
材料科学
·
分析化学
·
纳米技术
·
生物传感
·
表面科学
✓ 已验证
DOI
高影响因子
IONICS
·
2019
·Vol. 26
·期 2
·649-660
·
IF 2.289
Yan Honglin,Ru Qiang,Gao Ping,Cheng Shikun,Ling Francis Chi-Chung
In the past few years, silane coupling agents are often used to modify the surface of silicon materials; however, researches in preparation of SiO X -based materials pyrolyzed from silane coupling agents are seldom reported. Hence, in order to prepare amorphous SiO X @C anodes for Li-ion storage, we adopted three kinds of silane coupling agents as organic silicon sources. The results show that silane coupling agents with vinyl group is the optimum organic silicon source. Owing to the strong chemical bonds of Si–O–C, amorphous SiO X particles are uniformly embedded in carbon matrix, forming monodisperse microbeads architecture with good buffer abilities. Therefore, the V-SiO X @C anodes derived from silane coupling agents with vinyl groups show good electrochemical performance, retaining a reversible discharge capacity of 940 mAh g −1 at a current density of 100 mA g −1 after 200 cycles, and it still depicts a good long-term cycling durability, maintaining 739 mAh g −1 at a current density of 400 mA g −1 after 400 cycles.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
功能材料
·
锂离子电池
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2023
·
IF 9.2
Tianyao Ding,Dong Zheng,Huainan Qu,Weixiao Ji,Xiaoxiao Zhang,Dongping Lu,Gongwei Wang,Deyang Qu
An in-situ electrochemical optical diagnosis is the key to the investigation of electrode interface during a redox reaction . Because the morphology changes particularly, dendrite formation, dendrite shapes, solid electrolyte interface formation and gas generation can be revealed visually. The challenge of ensuring uniform current density on a flat Li anode in a liquid electrolyte is addressed and uniform Li plating is demonstrated. The dendrite shape change under different reduction current density is discussed. The Li dendrite shape change and the performance of Li anodes with a surface lamination of graphite and red phosphate are used as examples to demonstrate the capability of the in-situ optical cell. An in-situ electrochemical optical cell used in the investigation of the increasingly popular solid-state Li batteries has its own challenges. Due to the untransparent nature of a solid-state electrolyte, an optical investigation on a solid-state electrolyte Li battery needs to be done by exposing the cross-section of the cell. In addition, it is very difficult to assemble an optical cell with a brittle and fragile solid-state electrolyte in a glove box. A set of formation and transfer dies, and an optical cell are introduced. The Li dendrite growth at the interface can be observed in a solid-state Li cell.
研究领域:
电化学
·
材料科学
·
能源存储
·
固态电池
·
界面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2019
·
IF 7.467
S.Z. Zhang,X.L. Wang,X.H. Xia,Z.J. Yao,Y.J. Xu,D.H. Wang,D. Xie,J.B. Wu,C.D. Gu,J.P. Tu
Interfacial issues have been the main obstacle to the development of solid-state batteries . In this work, we design a solid hybrid polymer electrolyte based on poly-(ethylene glycol) diacrylate and succinonitrile (PSSE) with a liquid state precursor. An intimate interface between PSSE and Li 4 Ti 5 O 12 @vertical graphene (LTO@VG) electrode with three-dimensional array structure is cleverly constructed by infiltrating fluid precursor of PSSE into vertical pores of LTO@VG followed by polymerization and solidification of PSSE. The quasi-solid-state LTO@VG//PSSE//Li and LiFePO 4 //PSSE//LTO@VG full cells exhibit superior electrochemical performance since the active materials are closely contacted by the conductive skeleton and ion-conductive electrolyte. The LTO@VG//PSSE//Li cells maintain 85.7% capacity retention after 400 cycles at 2 C and the LFP//PSSE//LTO@VG full cells still reach 99.0% capacity retention after 200 cycles at 0.5 C. This novel strategy for interface engineering paves the way for achieving high-performance solid-state batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
高分子化学
·
纳米材料
·
界面科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 52
·27259-27266
·
IF 3.708
Libin Yang,Feng Xin,Junzhong Lin,Zhuang Zhuang,Rui Sun
In this study, a hydrothermal synthesis was developed to prepare a thin titanium silicalite-1 catalyst layer in the internal channels of the honeycomb cordierite support, which was used in a continuous heterogeneous reaction. The as-prepared thin TS-1 catalyst layer was characterized by SEM, XRD, UV-vis and ATR-FTIR methods. Multiple hydrothermal syntheses were used for controlling the crystalline growth to optimize catalytic activity and lifetime. Moreover, a monolithic TS-1/cordierite reactor with external looping was utilized to investigate the characteristics of the continuous heterogeneous ammoximation reaction without the organic solvent tert-butanol (TBA). The reaction results showed that the conversion of cyclohexanone and selectivity of oxime approached more than 0.96 and 0.98, respectively. When compared with the reaction using TBA as the reaction solvent, the activity of the monolithic TS-1/cordierite showed no differences except for a longer lifetime.
研究领域:
化学工程
·
催化化学
·
材料科学
·
工业化学
·
绿色化学
✓ 已验证
DOI
高影响因子