RSC Advances
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2021
·Vol. 11
·期 29
·17595-17602
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IF 3.361
Shengquan Fu,Yueyue Xiao,Xinxin Yu,Tianxing Xiang,Fei Long,Junyan Xiao,Zhiliang Ku,Jie Zhong,Wei Li,Fuzhi Huang,Yong Peng,Yibing Cheng
The preparation of CsyFA1−yPbIxBr3−x-based perovskite by ultrasonic spraying has valuable application in the preparation of tandem solar cells on textured substrates due to its excellent stability and the advantages of large-area uniform preparation from the spraying technology. However, the bandgap of perovskite prepared by spraying method is difficult to adjust, and perovskites with a wide bandgap have the issue of phase instability. Here, we improved the crystallinity of the perovskite by simply controlling the post-annealing temperature. The results show that perovskite film prepared by hybrid spray method has the best crystallinity and device performance at a post-annealing temperature of 170 °C. On this basis, the bandgap of perovskite was changed from 1.53 eV to 1.76 eV by controlling the ratio of the organic halogen precursor solution. When the bandgap is 1.57 eV, a perovskite solar cell with an efficiency of 18.31% is obtained.
研究领域:
材料科学
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能源技术
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DOI
PubMed
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2020
·Vol. 39
·期 1
·122-132
·
IF 3.154
Yu Man-Man,Yang Wei-Jun,Niu De-Yu,Cai Xiao-Xia,Weng Yun-Xuan,Dong Wei-Fu,Chen Ming-Qing,Xu Peng-Wu,Wang Yang,Chu Hong,Ma Pi-Ming
In this work, hydroxyl-terminated oxalamide compounds N 1 , N 2 -bis(2-hydroxyethyl)oxalamide (OXA1) and N 1 , N 1′ -(ethane-1,2-diyl)bis( N 2 -(2-hydroxyethyl)oxalamide (OXA2) were synthesized to initiate the ring-opening polymerization of L-lactide for preparation of oxalamide-hybridized poly(L-lactide) (PLA OXA ), i.e. , PLA OXA1 and PLA OXA2 . The crystallization properties of PLA were improved by the self-assembly of the oxalamide segments in PLA OXA which served as the initial heterogeneous nuclei. The crystal growth kinetics was studied by Hoffman-Lauritzen theory and it revealed that the nucleation energy barrier of PLA OXA1 and PLA OXA2 was lower than that of PLA. Consequently, PLA OXA could crystallize much faster than PLA, accompanied with a decrease in spherulite size and half-life crystallization time by 74.8% and 86.5% (T = 125 °C), respectively. In addition, the final crystallinity of PLA OXA1 and PLA OXA2 was 6 and 8 times higher, respectively, in comparison with that of neat PLA under a controlled cooling rate of 10 °C/min. The results demonstrate that the hybridization of oxalamide segments in PLA backbone will serve as the self-heteronucleation for promoting the crystallization rate. The higher the content of oxalamide segments (PLA OXA2 compared with PLA OXA1 ) is, the stronger the promotion effect will be. Therefore, this study may provide a universal approach by hybridizing macromolecular structure to facilitate the crystallization of semi-crystalline polymer materials.
研究领域:
材料科学
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高分子化学
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 18
·
IF 1.86
Binshuang Wu,Xiaoqing Zeng,Linbo Wu,Bo-Geng Li
In order to obtain high performance bioplastics and thermoplastic elastomers, P(LLA-mb-BSA) multi-block copolymers containing 30 wt % and 70 wt % soft segment (PLBSA30 and PLBSA70 for short) were synthesized via chain extension and coupling of poly(L-lactic acid) (PLLA) and poly(butylene succinate -co- adipate) (PBSA) prepolymers in the presence of 1% nucleating agent (NA). They were characterized with proton nuclear magnetic resonance ( 1 H NMR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), polarizing optical microscopy (POM), thermal gravimetric analysis (TGA), transmission electron microscope (TEM), and tensile and impact test. The relatively high molecular weights of ( M n 8200 g/mol and 3100 g/mol for PLLA and PBSA, respectively) the polyester sequences are helpful to improve the PLLA crystallization and the flexibility of the PBSA soft segment. Nucleation effect further accelerates the crystallization of PLLA segment. The synergistic effect of these factors results in good balance between stiffness and toughness. PLBSA30s containing 1% zinc citrate (ZnCC) or talc behave as ultra-tough bioplastics with ultrahigh impact strength over 50 kJ/m 2 and excellent tensile properties. PLBSA70 containing 1% ZnCC possesses elongation at break of 600% and retains high modulus (56 MPa) and strength (16 MPa) and therefore behaves as an excellent thermoplastic elastomer. The excellent and balanced properties would extend the end applications of these PLLA-based materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44777.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Zhengliang Zhao,Zhu Shu,Jun Zhou,Tiantian Li,Fei Yan,Wenbin Wang,Lina Xu,Lulu Shi,Zihao Liao
Improving the crystallinity of polymeric carbon nitride has been proved highly efficient for advanced photocatalysis . Nevertheless, controllable tuning the in-plane and interlayer crystallinity of crystalline carbon nitride has not been realized and their specific effect on photocatalysis is not clear yet. Herein, we proposed a facile one-step approach to selectively fabricate the in-plane or interlayer ordered crystalline carbon nitride by calcining melamine with KOH and NH 4 Cl at different KOH/NH 4 Cl ratios. Specifically, a high KOH/NH 4 Cl ratio results in sample with a highly in-plane integrity while a low ratio leads to a more orderly interlayer stacking. All the crystalline carbon nitride samples exhibit significantly boosted photocatalytic H 2 evolution reaction rate as compared to polymeric carbon nitride, suggesting the positive contribution of enhanced crystallinity to photocatalytic activity. More importantly, the as-prepared sample with a highly in-plane integrity surpasses another sample with a more orderly interlayer stacking in photocatalytic performance, benefitting from its highly in-plane ordered structure, which extends light-harvesting range and promotes exciton dissociation. This work provides a platform to investigate the structure activity relationship between crystallinity and photocatalytic properties of crystalline carbon nitride.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
Advanced Electronic Materials
·
2021
·Vol. 7
·期 12
·2000893
·
IF 7.295
Mingxing Cao,Zhihong Wang,Liwen Ma,Liwen Zhang,Man Wang,Yangsi Liu,Jian He,Xiaoli Xi
Tungsten ditelluride (WTe 2 ) is arising as an attractive material in magnetoresistance (MR) properties filed. The magnetoresistance properties of WTe 2 makes it an ideal material for its magnetoresistive heads of computer and magnetic sensor device applications. So far, people have developed various controlled synthesis methods to produce large-quantity uniform flat WTe 2 crystals. Nevertheless, none of the methods are sustainable, some methods use reducing gases, and some use very long heat preservation, and the process is very complicated. Here, a mild and fast self-flux method is described for WTe 2 synthesis that can avoid producing reducing gases. After conducting structural and physical tests, it is found that annealing time is critical for WTe 2 structure formation. Long annealing time improves the crystallinity of WTe 2 and makes its texture more obvious, increasing the conductivity of WTe 2 . Therefore, it will lead to the anomalous nonsaturating positive magnetoresistance with different field dependent behaviors, reaching the ultrastrong magnetoresistive value of 1040% at 5 K and 14 T. The results provide a sustainable approach for uniform WTe 2 crystal synthesis, which will benefit the large-quantity production of WTe 2 magnetoresistive materials.
研究领域:
材料科学
·
物理学
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高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2022
·
IF 4.966
Guoqiang Wang,Yakun Dong,Xingyu Hao,Li Zhang,Xiang Chi
Currently, a growing focus is devoted to the creation and utilization of renewable resources for bio-based polyesters due to the shortage of oil resources. Since 2,5-furandicarboxylic acid (FDCA) has been described as one of the most promising platform compounds, FDCA-based polyesters have been rapidly developed. Poly(decylene terephthalate- co -decylene furandicarboxylate) (PDTFs) in this study were prepared from dimethyl terephthalate (DMT), 1,10-decanediol (DDO) and dimethyl 2,5-furandicarboxylate (DMFD). By using 1 H NMR and 13 C NMR, the polyesters' chemical structure was verified. The thermal properties and the thermal stability of the polyesters were analyzed by Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis (TGA). All polyesters underwent mechanical testing to ascertain their Young's modulus , tensile strength , and elongation at break. All polymers are semi-crystalline materials. The crystal texture of PDTF24 is equivalent to that of poly(decylene terephthalate) (PDT). However, the crystal structures of PDTF48 and PDTF76 are similar to that of poly(decylene furandicarboxylate) (PDF). All polymers exhibit high thermal stability. PDF has the highest tensile strength, probably because the oxygen atom on the furan ring results in stronger intermolecular interactions . When the content of the decylene furandicarboxylate unit reaches 48%, Young's modulus reaches its lowest value (96.6 MPa), but its elongation at break reaches its highest value (1098%) due to the lowest crystallinity .
研究领域:
材料科学
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化学工程
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高影响因子
Journal of Materials Chemistry C
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2023
·Vol. 11
·期 18
·6010-6017
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IF 6.4
Tianran Zhang,Qinzhao Sun,Zepeng Wang,Ruirui Kang,Fang Kang,Rong Xue,Jiping Wang,Lixue Zhang
Electrostatic energy storage dielectric polymers are essential for pulsed power applications due to their high power density. However, it suffers from low energy density and poor efficiency at high temperatures, which seriously hinders its application. Herein, a polyetherimide – MgO/polymethyl methacrylate/poly(vinylidene fluoride) – polyetherimide sandwich-structured composite was prepared by solution casting and hot-pressing. The experimental results show that MgO acted as a nuclear agent to promote the crystallization of PVDF, thereby improving the polarization at high temperatures. At 150 °C, the optimized composite exhibited a high discharge energy density of 3.34 J cm−3 when the charge–discharge efficiency was above 90% at 350 MV m−1. MgO alleviated both the ferroelectric loss and conduction loss at the low electric field as well, resulting in high polarization and high efficiency at the low electric field. Through this work, we made a new attempt to enhance the energy storage performance of high-temperature polymer-based dielectric composites under a low electric field.
研究领域:
材料科学
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电介质物理
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DOI
高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Xiamin Lv,Huasheng Man,Lijuan Dong,Jianying Huang,Xiangyang Wang
Carbon dots (CDs) have been a new class of fascinating carbon-based fluorescent nanomaterials. In the present work, new N -doped CDs with highly crystalline graphite structures are prepared from renewable precursors, chitosan and tartaric acid, and are well characterized. The prepared CDs are applied as a biocompatible fluorescent sensor for the sequential detection of Fe 3+ and AA. Among various transition metal ions, Fe 3+ can selectively quench the fluorescence of CDs. Upon the further addition of AA, the quenched fluorescence of CDs is then restored as Fe 3+ is reduced to Fe 2+ by AA, which can be utilized for the fluorescent determination of AA. A good linear relationship in the range of 0–150 μM of AA concentration is established with a low detection limit of 0.02 µM. Moreover, the practical applications of this fluorescent sensing method in measurement of AA in food samples are successfully realized with satisfactory results.
研究领域:
材料科学
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分析化学
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生物医学
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DOI
PubMed
高影响因子
Polymers
·
2025
·Vol. 17
·期 11
·1537
·
IF 4.9
Haoyang Zhang,Jiyu He,Xiangmei Li
PA66 is a widely used engineering plastic, but its flammability reduces safety during application. The 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) and its derivatives are a class of flame retardants with excellent flame-retardant efficiency, which can significantly improve the flame retardancy of PA66. This work synthesized a DOPO derivative flame retardant, DT, containing multiple P/N elements and comprehensively characterized its structure using FTIR and NMR. Flame-retardant PA66 materials were prepared by twin-screw extrusion blending with PA66, and their thermal stability, crystallization properties, flame retardancy, and mechanical properties were investigated. When the DT content reached 15%, the vertical burning classification test achieved the UL-94 V-0, and the limiting oxygen index (LOI) rose up 27.2%. In the cone calorimeter test, the peak of heat release rate (PHRR) and total heat release (THR) of the material decreased significantly, and a distinct char layer formed, increasing NH3release and decreasing the C-H structure after combustion, improving PA66 flame-retardant properties.
研究领域:
材料科学
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高分子化学
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DOI
PubMed
高影响因子
ACS Omega
·
2025
·
IF 4.3
Xinpeng Zhang,Hongli Bian,Xiangze Meng,Jing Yuan,Jianping Ding,Wanli Li,Jun Xu,Baohua Guo
Poly(butylene adipate-co-terephthalate) (PBAT) is one of the most promising biodegradable copolyesters for addressing “white pollution” and has made significant progress in industrial production, particularly in packaging and mulching film applications. However, melt elasticity and the rapid biodegradation rate of linear PBAT limit the broader application. In this study, a series of novel PBAT copolyesters with a low content of branch units (1.3–1.6%) were synthesized from adipic acid (AA), terephthalic acid (PTA), 1,4-butanediol (1,4-BDO), and branching monomers with fixed side chain length through esterification and polycondensation. A comprehensive investigation into the macromolecular structure of branched PBAT was conducted. A “Memoryless Random Model” combined with 1H-NMR analysis was used to calculate the number-average sequence length, which proved the existence of random block sequences. Both linear and branched PBAT copolymers exhibited relatively high and similar molecular weights of 6.3 × 104 Da and above. The conformational parameters g and B3w were determined by gel permeation chromatography (GPC) coupled with triple detectors, thereby providing a clear definition of the branching characteristic. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) analyses revealed two crystalline forms in PBAT, with the β-form predominating in linear PBAT and a decrease in crystallinity in branched PBAT. The enzymatic hydrolysis experiment showed that the branched side chain reduced the hydrolysis rate, and the existence of consecutive sequences (≥3) was proved by LC–MS. The copolymers demonstrated higher complex viscosity and tanδ at the same frequency, indicating enhanced melt viscosity and elastic response. The deviation of the end slope in the Han curve also proved the existence of BA-BT random block sequence and complex relaxation behavior.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Xue Ma,Xuefei Chen,Xiaohua Wang,Xiaohua Yang,Zengwen Yao,Houyong Yu,Yunyun Zhang
Polyamide 66 (PA66) has garnered significant attention due to its exceptional properties; unfortunately, its flammability is challenging. Adding flame retardants (FRs) is a primary approach to enhance PA66 flame retardancy. This study developed a highly flame-retardant PA66 composite film by adding corn-like functional nanohybrids (CNC/Al 2 O 3 ). Interestingly, CNC/Al 2 O 3 nanohybrids not only formed hydrogen bond interactions with PA66 but also improved crystallization properties as heterogeneous nucleating agents, resulting in the excellent mechanical properties of PA66 composite film. Remarkably, the incorporation of 3 wt% CNC/Al 2 O 3 nanohybrids into PA66 matrix contributed to increasing the LOI to 28.5 %. The pHRR, THR, and TSR were reduced obviously by 55.7 %, 15.3 %, and 65.2 %, respectively. The excellent flame retardancy of PA66 composite film was attributed to the forming of a compact carbon layer catalyzed by the CNC/Al 2 O 3 nanohybrids. Besides, the homogeneous distribution of CNC/Al 2 O 3 nanohybrids endowed the composite film with excellent heat insulation, and the heat insulation rate was up to 31.9 %. Thus, such PA66 composite films with excellent flame retardancy, heat insulation, and mechanical properties could meet the broader application requirements.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Zhixiang Yan,Huiting Yang,Shuo Zheng,Zhiyong Tan
Enhancing the dielectric properties of polymer materials plays a crucial role in reducing the volume, weight, and cost of dielectric capacitors. In this work, polyurethanes (PUs) for high dielectric performance were fabricated using poly(tetramethylene ether glycol) (PTMG) and polycarbonate diol (PCDL) as soft segments and hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4′-diphenylmethane diisocyanate (MDI), and toluene diisocyanate (TDI) as hard segment components. The effects of the type and chemical structure of diisocyanate on the microphase separation, crystallization, dielectric properties, and mechanical properties of PUs were investigated. Within the frequency range of 10 −1 –10 5 Hz, MDI-PU exhibited the lowest conductivity (7.32 × 10 −9 S·m at 10 −1 Hz) and the smallest dielectric loss (0.014 at 10 3 Hz), demonstrating excellent insulation properties. This was because the aromatic hard segments of MDI were more rigid, resulting in a tighter molecular arrangement, which facilitates the reduction of polarization loss and charge migration. In addition, the crystallinity and dielectric constant of HDI-PU were higher than those of IPDI-PU, MDI-PU, and TDI-PU. This study demonstrates the deep influence of different diisocyanates on the properties of polyurethanes, revealing the importance of hard-segment structure, crystallinity, and polarization processes in modulating the dielectric properties.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）