RSC Advances
·
2017
·Vol. 7
·期 82
·52024-52029
·
IF 3.108
Xiao-Fen Sun,Zhongxia Wang,Wei-Qiang Liao,Peng-Fei Li,Jixing Gao,Yi-Yang Huang,Hai-Peng Chen,Heng-Yun Ye,Yi Zhang
In this paper, three new hybrid phase transition compounds, [Hmpy]CdBr3 (1, Hmpy = N-methylpyrrolidinuium cation), [Hmpy]2CdBr4 (2) and [Hmpy]3CdBr3·CdBr4 (3), were synthetized by means of regulating the ratio of reactants. Systematic characterizations consisting of variable temperature X-ray single crystal diffraction, differential scanning calorimetry (DSC) and dielectric measurements reveal that 1 with infinite one-dimensional (1D) [CdBr3]n− chains undergoes a phase transition around 278 K; 2 with isolated [CdBr4]2− tetrahedrons exhibits a high-temperature phase transition close to 367 K, accompanied by prominent switchable dielectric behavior. Interestingly, 1D [CdBr3]n− chains and isolated [CdBr4]2− tetrahedrons both exist in 3, associated with a phase transition at 320 K. The phase transitions in the three compounds are originated from the order-disorder transitions of the Hmpy cation. It is expected that our finding would promote the development of hybrid dielectric transition materials with adjustable properties.
研究领域:
材料化学
·
凝聚态物理
·
晶体工程
·
功能材料
·
介电材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Xijun Wei,Yanhong Li,Huarong Peng,Ming Zhou,Yingqing Ou,Yibin Yang,Yunhuai Zhang,Peng Xiao
In this work, hollow CoS nanobox (noted as HCSN) have been successfully synthesized via annealing and hydrothermal process from zeolitic imidazolate framework (ZIF-67) template. When tested as positive electrode materials in alkaline aqueous electrolyte, it shows high specific capacitance of 720 F g −1 at a current density of 1 A g −1 , good rate capability (82.1%) and good cycling stability with 86.4% capacitance retention over 10,000 cycles at 10 A g −1 . To further demonstrate the advantages of our ZIF-67 derived materials, asymmetric energy storage device was assembled (HCSN//NC), where the as-prepared HCSN was employed as the anode and ZIF-67-derived nanoporous carbon (noted as NC) as the cathode. This device achieves high energy density (80 Wh kg −1 at a specific power density of 882 W kg −1 ), good rate capability (53.3 Wh kg −1 even at a specific power density of 7.9 kW kg −1 ) and long-term stability up to 10,000 cycles. More importantly, it could simultaneously light up 12 LEDs in parallel, demonstrating its potential in practical applications.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
功能材料
·
应用物理
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2018
·
IF 2.207
Hongyu Shi,Na Li,Zhixia Sun,Tianqi Wang,Lin Xu
TiO 2 nanoparticles are commonly used as versatile precursors to make functional nanocomposite materials. However, the surface defects at grain boundaries of TiO 2 nanoparticles significantly affect the photoelectric properties of TiO 2 nanomaterials . In this work, we firstly prepared nanocomposites of TiO 2 and polyoxometalates (POMs) in which different POMs, including titanium-substituted POMs K 5 [PW 11 TiO 40 ] and K 7 [PW 10 Ti 2 O 40 ], are incorporated with TiO 2 nanoparticles so as to make an interface modification on grain boundaries of TiO 2 nanoparticles. Then the photoconductivities of the TiO 2 /POM nanocomposites were investigated through measurement of photocurrent responses, current-voltage curves, Mott-Schottky plots and surface photocurrent spectra. Compared with pure TiO 2 nanoparticles, TiO 2 /POM nanocomposites exhibit superior photoelectric properties, benefitting from the interface modification from different POMs. The gas sensing performance for acetone was also explored by use of the as-prepared photoconductive devices, and TiO 2 /PW 11 Ti exhibited a high gas sensing performance.
研究领域:
材料科学
·
纳米科技
·
半导体物理
·
传感器技术
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 19
·11701-11714
·
IF 2.599
Wei Xiuzhen,Hong Jialiang,Zhu Shuangshuang,Chen Jinyuan,Lv Bosheng
Polyethyleneimine (PEI) of various molecular weights and trimesoyl chloride (TMC) were utilized to prepare composite nanofiltration (NF) membranes via interfacial polymerization. The changes in the surface structure and chemical composition of the prepared membranes were evaluated using SEM, ATR-FTIR, XPS and surface potential measurements. The pure-water flux and rejection rates of the inorganic salts (MgCl 2 , MgSO 4 , Na 2 SO 4 and NaCl) through the resultant NF membranes were also investigated. The results showed that the performance of the composite NF membranes was significantly affected by the molecular weight of the PEI. Notably, the permeate flux and rejection rate of the NF membranes increased with the PEI molecular weight. In addition, when the NF membranes were used to treat actual wastewater from the electroplating industry, the NF membranes presented high-efficiency separation properties for heavy metal ions. The rejection rates of the NF membranes at 0.4 MPa for chromium, nickel, zinc and copper ions reached 92.6, 89.6, 89.2 and 86.3%, respectively.
研究领域:
材料科学
·
膜分离技术
·
环境工程
·
高分子化学
·
水处理
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Wenbin Wu,Ping Zhang,Siqi Chen,Xiaohong Liu,Guilin Feng,Meihua Zuo,Wangyan Xing,Bin Zhang,Weifeng Fan,Heng Zhang,Ping Zhang,Jie Zhang,Wei Xiang
O3 phase layered oxides are highly attractive cathode materials for sodium-ion batteries because of their high capacity and decent initial Coulombic efficiency. However, their rate capability and long cycling life are unsatisfactory due to the narrow Na + transfer channel and irreversible phase transitions of O3 phase during sodiation/desodiation process. Constructing O3/P2 multiphase structures has been proven to be an effective strategy to overcome these challenges. In this study, we synthesized bi-phasic structured O3/P2 Na(Ni 2/9 Fe 1/3 Cu 1/9 Mn 1/3 ) 1- x Mn x O 2 ( x = 0.01, 0.02, 0.03, 0.04, 0.05) materials through Mn doping during sodiation process. Benefiting from surface P2 phase layer with the enhanced Na + transfer dynamics and high structural stability , the Na(Ni 2/9 Fe 1/3 Cu 1/9 Mn 1/3 ) 0.98 Mn 0.02 O 2 (NFCM-M2) cathode delivers a reversible capacity of 139.1 mA h g −1 at 0.1 C, and retains 71.4 % of its original capacity after 300 cycles at 1 C. Our work provides useful guidance for designing multiphase cathodes and offers new insights into the structure-performance correlation for sodium-ion cathode materials.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
✓ 已验证
DOI
高影响因子
SOLID STATE IONICS
·
2018
·
IF 2.751
Yuzhen Duan,Junming Guo,Mingwu Xiang,Jinyu Zhu,Changwei Su,Hongli Bai,Xiaofang Liu,Wei Bai,Rui Wang
A series of single crystalline spinel LiNi x Mn 2- x O 4 (0 ≤ x ≤ 0.10) cathode materials were synthesized in virtue of a facile solution-combustion approach. The morphology and the structure of all as-prepared samples were synthetically investigated with the X-ray diffraction (XRD), the scanning electron microscopy (SEM), the high-resolution transmission electron microscopy (HRTEM), and the X-ray photoelectron spectrometer (XPS). According to these investigation results, Ni-doping content has a significant impact on the control of morphology and crystalline structure, hence the as-prepared LiNi x Mn 2- x O 4 samples exhibit polyhedral morphology with high crystallinity and average size of 100–200 nm. This unique polyhedral crystal structure has numerous surfaces fitting the (111) crystalline orientation which exhibit the smallest Mn dissolution in electrolytes, whilst stabilizing the spinel framework. Owing to the merits of both single crystalline polyhedral structure and appropriate Ni-doping, the as-obtained LiNi x Mn 2- x O 4 cathodes reveal enhanced rate capability coupled with long cycling performance. In especial, the LiNi 0.08 Mn 1.92 O 4 presents a initial discharge capacity of 101.3 mAh/g and ultralong cycle stability up to 2000 cycles at 1C, whilst showing enhanced cycle performance when temperature increases to 55 °C. Excellent capacity retention of 72% and 63% is also obtained after 1000 cycles even at high current rate of 5C and 10C. This study may contribute to an effective candidate approach for the obvious improvement on lithium ion batteries in term of electrochemical activity.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
纳米材料
·
固态化学
·
电池技术
✓ 已验证
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Ping He,Yu Zhang,Zhenguo Wang,Peng Min,Zhiming Deng,Lulu Li,Lvxuan Ye,Zhong-Zhen Yu,Hao-Bin Zhang
Graphene has been widely studied for its excellent properties of outstanding conductivity, strength , and flexibility. However, interlayer defects formed during the macroscopic assembly of graphene nanosheets will severely degrade the performance of graphene films. Herein, a strategy combined with trace carboxyl graphene oxide (GO), mild reduction, and chemical crosslinking is employed to minimize the interlayer defects for enhancing both the conductivity and mechanical strength of graphene films. The trace carboxyl feature of GO allows nanosheets to assemble orderly into highly oriented GO films . Subsequently, the mild chemical reduction preserves the highly oriented and packed microstructure. Coupling with further crosslinking by introducing conjugated molecules with pyrene terminal groups (1-pyrene butyric acid-1,6-hexane diamine, PHD) to provide extra π-π bonds, both the mechanical strength and conductivity of graphene films are improved to 548.4 MPa and 1.7 × 10 5 S m −1 , respectively. In addition, the graphene film with only ∼2 μm in thickness possesses an excellent electromagnetic interference shielding effectiveness (EMI SE) of ∼40 dB and a specific shielding effectiveness of up to 74 278 dB cm 2 g −1 in a wide frequency range of 8.2–40.0 GHz. Thus, this study provides an energy-saving fabrication route for mechanically strong, effective thermal management and EMI shielding films.
研究领域:
材料科学
·
纳米科技
·
高分子化学
·
功能材料
·
电磁屏蔽
·
热管理
✓ 已验证
DOI
高影响因子
Small
·
2019
·Vol. 15
·期 7
·1804974
·
IF 10.856
Na Li,Pingping Wei,Linan Yu,Junyi Ji,Jiupeng Zhao,Chuanbo Gao,Yao Li,Yadong Yin
The dynamic optical switch of plasmonic nanostructures is highly desirable due to its promising applications in many smart optical devices. To address the challenges in the reversibility and transmittance contrast of the plasmonic electrochromic devices, here, a strategy is reported to fabricate color switchable electrochromic films through electro-responsive dissolution and deposition of Ag on predefined hollow shells of Au/Ag alloy. Using the hollow Au/Ag alloy nanostructures as stable seeds for site-specific deposition of Ag, elimination of the random self-nucleation events is enabled and optimal reversibility in color switching is allowed. The hollow structure further enables excellent transmittance contrast between the bleached and colored states. With its additional advantages such as the convenience for preparation, high sensitivity, and field-tunable optical property, it is believed that this new electrochromic film represents a unique platform for designing novel smart optical devices.
研究领域:
材料科学
·
纳米科技
·
光学工程
·
功能材料
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF SUPERCRITICAL FLUIDS
·
2024
·
IF 3.4
Jianqiao Yang,Yining Ding,Fen Zhao,Shuzhong Wang,Yanhui Li,Donghai Xu
In this study, a Cr coating was fabricated on Ni-based alloys to prevent under-deposit corrosion. The effect of salt deposition on the structural integrity of the Cr coating in SCW environment with/without oxygen was investigated. Results show that the Cr coating kept its integrity after exposure in SCW environment, successfully avoided the metallic ions leaching from Ni-based alloys. The structure of the oxide layer after exposure is a thin Fe 2 O 3 or FeCr 2 O 4 layer and a Cr 2 O 3 layer. The oxidation rate of the Cr coating decreased to one third of the sample after exposure in the same environment without salt deposit layer, indicating that the inward mass-transfer of oxygen to the alloy surface was inhibited by the salt deposit layer. The volume expansion of the sample due to the growth of Cr oxide layer was restrained by the salt deposit layer, forming a growth stress in the coating.
研究领域:
材料科学
·
腐蚀科学
·
高温材料学
·
表面工程
·
能源材料
·
化学工程
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2018
·
IF 3.485
Xiong Xu,Jianying Yu,Lihui Xue,Bianyang He,Wei Du,Huang Zhang,Ying Li
The excellent comprehensive performance of SBS modified bitumen (SMB), during a long-term thermo- and photo-oxidative exposure, will fail to satisfy the pavement requirement. In this paper, the synergistic effect of 4,4′-diphenylmethane diisocyanate (MDI) and 1,4-butanediol diglycidyl ether (BUDGE) on the molecular weight of aged SBS was firstly studied, through a simulation, to confirm whether a new polymer structure can be obtained. Then, the reactive rejuvenating system containing MDI, BUDGE and bituminous composition returning agent (MDI-BUDGEs) was applied in the rejuvenation of aged SMB. The results show that the rebuilt molecular structure of aged SBS can be obtained with the combination of MDI and BUDGE. Meanwhile, MDI-BUDGEs can improve the low-temperature ductility and inhibit the sharp fall of the softening point of aged SMB, while decrease the viscosity-temperature response at 120–165 °C. Also, MDI-BUDGEs can contribute for increasing the viscous component, improving the fatigue resistance and remaining the high-temperature performance grade of aged SMB, and moreover, decrease the limited elastic modulus and the elastic-plasticity transition rate to avoid the occurrence of the brittle failure within a small strain range.
研究领域:
道路工程材料
·
高分子材料老化与修复
·
沥青化学
·
流变学
·
建筑材料耐久性
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2018
·
IF 6.945
Zhaomin Wang,Yong Cheng,Qian Li,Limin Chang,Limin Wang
Metallic Sb is deemed as a promising anode material for lithium ion batteries (LIBs) due to its flat voltage platform and high security. Nevertheless, the limited capacity restricts its large-scale application. Therefore, a simple and effective method to explore novel antimony trioxide with high capacity used as anode material for LIBs is imperative. In this work, we report a facile and efficient strategy to fabricate 1D hollow Sb 2 O 3 @TiO 2 composites by using the Kirkendall effect . When used as an anode material for LIBs, the optimal Sb 2 O 3 @TiO 2 composite displays a high reversible discharge capacity of 593 mAh g −1 at a current density of 100 mA g −1 after 100 cycles and a relatively superior discharge capacity of 439 mAh g −1 at a current density of 500 mA g −1 even after 600 cycles. In addition, a reversible discharge capacity of 334 mAh g −1 can also be obtained even at a current density of 2000 mA g −1 . The excellent cycling stability and rate performance of the Sb 2 O 3 @TiO 2 composite can be attributed to the synergistic effect of TiO 2 shell and hollow structure of Sb 2 O 3 , both of which can effectively buffer the volume expansion and maintain the integrity of the electrode during the repeated charge-discharge cycles.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
无机化学
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2017
·Vol. 29
·期 2
·982-988
·
IF 1.907
Jiayu Xian,Jieting Geng,Yan Wang,Lin Xia
Shape-memory polymers are important smart materials with potential applications in smart textiles, medical devices, and sensors. We prepared trans-1,4-polyisoprene, low-density polyethylene (LDPE), and high-density polyethylene (HDPE) shape-memory composites using a simple mechanical blend method. The mechanical, thermal, and shape-memory properties of the composites were studied. Our results showed that the shape-memory composites could memorize 3 temporary shapes, as revealed by the presence of broad melting transition peaks in the differential scanning calorimetry curves. In the trans-1,4-polyisoprene/LDPE/HDPE composites, the cross-linked network and the crystallization of the LDPE and HDPE portions can serve as fixed domains, and all crystallizations can act as reversible domains. We proposed a schematic diagram to explain the vital role of the cross-linked network and the crystallization in the shape-memory process.
研究领域:
高分子材料科学
·
生物医学工程
·
智能材料
·
功能高分子
·
热响应材料
✓ 已验证
DOI
高影响因子