Polymer Chemistry
·
2020
·Vol. 11
·期 15
·2708-2714
·
IF 5.342
Qingchi Ma,Xuefei Leng,Li Han,Pibo Liu,Chao Li,Songbo Zhang,Lan Lei,Hongwei Ma,Yang Li
Space-limited living species provide new insight into the regulation of the microstructure of isoprene units in alternating copolymers composed of isoprene (Ip) and 1,1-bis(4-dimethylsilylphenyl)ethylene (DPE-2SiH) using living anionic polymerization (LAP) modified with additives. It was found that suitable modifiers, such as sodium alkoxide (RONa), led to nearly 80% cis 1,4-addition of the isoprene units, while addition of potassium alkoxide (ROK) resulted in nearly 70% trans 1,4-addition. Through analysis, we know that the additives influence the angles between two subterminal benzene rings, and promote the regulatory effect of the space-limited living species on the cis and trans isoprene units. The larger the angle between two subterminal benzene rings, the more favourable are the conditions for addition polymerization in this form of microstructure. The copolymerization mechanism was investigated with the assistance of density functional theory (DFT) with Gaussian 09 and the corresponding characteristics of copolymers were determined with SEC, 1H NMR, 13C NMR and MALDI-TOF MS techniques. Due to the living features of LAP, this method can be employed as a key control of the copolymer chain sequence and microstructure at the same time.
研究领域:
高分子化学
·
材料科学
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DOI
高影响因子
RARE METALS
·
2025
·
IF 11
Zhang Tong,Shi Zhen-Dong,Xing Chang-Sheng,Wu Yun-Zhong,Liu Bin,Guan Ye-Kang,Jian Yu,Shuang Jia-Xu,Sheng Jie,Wang Li-Dong,Fei Wei-Dong
Graphene-copper (Gr-Cu) composites exhibit significant potential for industrial applications. Among the methods for fabricating Gr-Cu composites, the in-situ growth method stands out as a simple yet effective approach. However, graphene converted from liquid or solid molecules by the traditional in-situ growth method often exhibits numerous defects, thereby reducing its effectiveness in enhancing the electrical properties of the composites. To address this issue, we developed an innovative and efficient method, referred to as the “confined-parallel-space in-situ growth (CPS) method,” to grow high-quality graphene and fabricate high-conductivity Gr-Cu composites. Oleic acid was chosen as the small molecular carbon source and confined between copper sheets obtained by rolling dendritic copper powder. This carbon source underwent conversion into oriented, high-quality graphene in the confined space at high temperature. The high-quality graphene sheets serve as continuous electron transport channels, significantly improving the conductivity of the composite. The composite prepared by the CPS method (CPS-composite) demonstrates unique conductivity, exceeding that of standard annealed copper at temperatures above 40 °C and notably outperforming it by 3.2% at 160 °C. In addition, compared to the composite with a similar carbon content prepared by the traditional in-situ growth method, the yield strength of the CPS-composite increased by 23.6%, while the strengthening efficiency of graphene improved by 146.6%, achieving an ultrahigh value of 489 at a carbon volume fraction of 0.086 vol%. The CPS method emerges as a novel strategy for fabricating high-performance, low-cost, and large-scale graphene-copper composites using small molecular carbon sources, making it suitable for industrial production. Graphical abstract
研究领域:
材料科学
·
纳米技术
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DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Yuan Rao,Muhammad Tariq,Mingxia Wang,Xin Yu,Hao Liang,Qipeng Yuan
Liposomes (LIP) loaded with natural active ingredients have significant potential in the food industry. However, their low loading efficiency (LE) hampers the advancement of liposomal products. To improve the loading capacity of functional compounds, bionic oleosomes (BOLE) with a monolayer of phospholipid membranes and a glyceryl tricaprylate/caprate (GTCC) oil core have first been engineered by high-pressure homogenization. TEM revealed that the core of BOLE consists of GTCC instead of water, thereby extending the hydrophobic space. Steady-state fluorescence and active loading experiments confirmed that cholesterol (CH) detached from the phospholipid membrane and entered the oil core, where it repelled cannabidiol (CBD). Based on the extending hydrophobic space, CBD-BOLE was prepared and its LE was 3.13 times higher than CBD-LIP. The CBD-phospholipid ratio (CPR) of CBD-BOLE significantly improved at least 7.8 times. Meanwhile, the free radical scavenging activity of CBD was increased and cytotoxicity was reduced.
研究领域:
食品科学
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药学
·
纳米技术
·
生物技术
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DOI
PubMed
高影响因子
TALANTA
·
2024
·
IF 5.6
Xin Geng,Yanqiu Wang,Hongli Li,David Da Yong Chen
Characterization of chemical composition in cigarette smoke is essential for establishing smoke-related exposure estimates. Currently used methods require complex sample preparation with limited capability for obtaining accurate chemical information. We have developed an in situ solid-phase microextraction (SPME) method for online processing of smoke aerosols and directly coupling the SPME probes with confined-space direct analysis in real time (cDART) ion source for high-resolution mass spectrometry (MS) analysis. In a confined space, the substances from SPME probes can be efficiently desorbed and ionized using the DART ion source, and the diffusion and evaporation of volatile species into the open air can be largely avoided. Using SPME-cDART-MS, mainstream smoke (MSS) and side-stream smoke (SSS) can be investigated and the whole analytical protocol can be accomplished in a few min. More than five hundred substances and several classes of compounds were detected and identified. The relative contents of 13 tobacco alkaloids were compared between MSS and SSS. Multivariate data analysis unveiled differences between different types of cigarette smoke and also discovered the characteristic ions. The method is reliable with good reproducibility and repeatability, and has the potential to be quantitative. This study provides a simple and high-efficiency method for smokeomics profiling of complex aerosol samples with in situ online extraction of volatile samples, and direct integration of extracted probes with a modified ambient ionization technique.
研究领域:
分析化学
·
烟草科学
·
质谱分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
·
2024
·
IF 4.1
Yewei Xu,Haoran Zhu,Shijie Mo,Yangqing Mao,Chi Zhong,Ying Huang,Rui Yuan,Min Zheng,Mingru Zhou,Guanjun Chang
An indole-based porous organic polymer (PTIM) with antibacterial activity was prepared by Friedel-Crafts alkylation and supercritical drying from the self-made tri(1H-indol-3-yl)methane (TIM). The adsorption of 2,4,6-trinitrotoluene (TNT) by PTIM involved physisorption followed by chemisorption, and the mechanism was verified by theoretical simulation and experiment. The physisorption and chemisorption between PTIM and TNT as well as the suitable three-dimensional space size of cross-linked network in PTIM enabled PTIM to have an unprecedented adsorption capacity for TNT (399.2 mg/g). Meanwhile, the removal efficiency of PTIM for TNT was also very high, and it could reach more than 85% of the maximum adsorption capacity after only 1 h of adsorption. Furthermore, the adsorption capacity of PTIM to TNT in actual water samples was slightly less than that in the laboratory, while the adsorption equilibrium time (4 h) was much shorter than the laboratory data (13.75 h). As a result, PTIM could not only achieve primary purification of TNT wastewater from high concentration to low concentration, but also advanced purification from low concentration to standard discharge concentration. In addition, PTIM possessed excellent recycling performance, and the maximum adsorption capacity was still 97% of the initial capacity after five adsorption-desorption cycles Unexpectedly, PTIM also had good antibacterial activity, preventing bacteria from adhering to or covering the pores, and ensuring excellent adsorption capacity and recycling performance. These results showed that PTIM was a promising TNT adsorbent.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Yuanhua Xiao,Yang Kong,Xuezhao Wang,Haoran Luo,Gaozhan Yuan,Shiwei Zhang,Aiqing Zhang,Jun Zhou,Yuanyuan Fan,Ling Xin,Anle Wang,Shaoming Fang,Yujie Zheng
The intriguing characteristics of two-dimensional (2D) heterostructures stem from their unique interfaces, which can improve ion storage capability and rate performance. However, there are still challenges in increasing the proportion of heterogeneous interfaces in materials and understanding the complex interaction mechanisms at these interfaces. Here, we have successfully synthesized confined CoSe 2 within the interlayer space of Ti 3 C 2 T x through a simple solvothermal method, resulting in the formation of a superlattice-like heterostructures of CoSe 2 @Ti 3 C 2 T x . Both density functional theory (DFT) calculations and experimental results show that compared with CoSe 2 and Ti 3 C 2 T x , CoSe 2 @Ti 3 C 2 T x can significantly improve adsorption of Na + ions, while maintaining low volume expansion and high Na + ions migration rate. The heterostructure formed by MXene and CoSe 2 is a Schottky heterostructure, and its interfacial charge transfer induces a built-in electric field that promotes rapid ion transport. When CoSe 2 @Ti 3 C 2 T x was used as an anode material, it exhibits a high specific capacity of up to 600.1 mAh/g and an excellent rate performance of 206.3 mAh/g at 20 A/g. By utilizing CoSe 2 @Ti 3 C 2 T x as the anode and activated carbon (AC) as the cathode, the sodium-ion capacitor of CoSe 2 @Ti 3 C 2 T x //AC exhibits excellent energy and power density (125.0 Wh kg −1 and 22.5 kW kg −1 at 300.0 W kg −1 and 37.5 Wh kg −1 , respectively), as well as a long service life (86.3 % capacity retention over 15,300 cycles at 5 A/g), demonstrating its potential for practical 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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2025
·
IF 8.3
Huanyu Chen,Xingyu Huo,Jun Wang,Qiuyu Wang,Ziwen Wang,Bo Lv
A hydrogel CZS/NiS@HR for photocatalytic hydrogen production is fabricated through solvothermal synthesis of CdZnS (CZS) composites, followed by physical cross-linking and self-assembly. This material facilitates spatially oriented charge separation via heterojunctions, effectively suppressing electron-hole recombination. The hydrogen evolution rate reaches 65 mmol/g/h, with stable catalytic activity maintained at 45 mmol/g/h after five cycles. The hydrogel structure prevents the release of toxic Cd 2+ into the environment. Compared to CZS, the UV absorption edge of CZS/NiS@HR is significantly redshifted, confirming successful Ni-based heterojunction surface modification. The three-dimensional network of the hydrogel enhances H + diffusion, thereby improving photocatalytic hydrogen production efficiency while mitigating sulfide photo-oxygen corrosion and reducing catalyst costs. This study underscores the synergistic effects of heterojunctions and hydrogels in promoting sustainable photocatalytic hydrogen production.
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产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2023
·
IF 9.1
Jian Gao,Kangning Wu,Zongliang Xie,Jianying Li,Shengtao Li
Thermochromic phase change composites (TPC) exhibit versatile functions under electrothermal stimuli, which are extensively applied as packaging, insulation and circuit components in considerable advanced smart electronics. However, space charge accumulation under DC voltages is still a critical and universal issue for the serious deterioration of functionalities and life-span of TPC and electronics. This study presents a novel strategy of suppressing space charge in thermochromic phase change epoxy composites (TPCE) by constructing interfacial barrier from tribo-positive shell thermochromic phase change microcapsules. The strong tribo-positive melamine-formaldehyde (MF) shell of microcapsules can establish negative charge barriers in the interfaces between microcapsules and epoxy matrix through triboelectrification, which is directly verified by Kelvin probe force microscopy. Pulsed electroacoustic measurement results exhibit the space charge accumulation in TPCE under an extreme electric field strength of 50 kV/mm and an elevated temperature of 70 °C can be significantly diminished by 39.3% compared to that of neat epoxy resin after incorporating merely 1 phr MF shell microcapsules, affirming the effect of interfacial barrier on space charge inhibition. The interfacial barrier could improve the charge carrier dissipation and mitigating the space charge accumulation as confirmed by hopping conduction analysis. Moreover, DC breakdown strength of TPCE can also be enhanced by 12.3% and 6.1% with 1phr microcapsules at 30 °C and 70 °C compared to that of neat epoxy resin owing to the suppressed space charge. The results provide a potential approach of designing high-performance thermochromic phase change composites for smart electrical and electronic devices.
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 8
·3462-3470
·
IF 9.931
Rui Han,Jihui Gao,Siyu Wei,Yanlin Su,Yukun Qin
High-temperature sorption of CO2via calcium looping is a promising technology for the implementation of carbon capture and storage (CCS). However, the major drawback of this technology is the rapid deactivation of CaO sorbents due to sintering. Here, a facile and cost-effective limited-space metal organic chemical vapor deposition approach is proposed to develop CaO-based sorbents exhibiting a very high and cyclically stable CO2 uptake. The TEM results show that Al2O3 nanoparticles (4–8 nm) are uniformly coated onto CaO crystalline grains, thus effectively inhibiting the sintering of sorbents. After 20 severe cycles, the synthetic sorbent, stabilized by 10 mol% Al2O3, exceeded the CO2 uptake of the benchmark CaO by more than 300%. Furthermore, the influence of Ca-based precursors on the synthetic sorbent's cyclic CO2 uptake was established. The result shows that the sorbents synthesized from different Ca-based precursors all demonstrate high cycling stability, which means that low-cost and high-performance sorbents can be synthesized through selecting a low-cost Ca precursor, such as CaCO3.
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2022
·Vol. 10
·期 39
·14580-14589
·
IF 8.067
Changqian Li,Feitong Chen,Kaiyu Wang,Qing Yao,Jie Zhang,Qiqi Zhao,Qi Huang,Huiling Zhu,Jianxu Ding
Metal halide perovskite materials exhibit remarkable optoelectronic properties due to their unique crystal and electronic structures. In perovskite polycrystalline films, the carrier transport is easily affected by grain boundaries where the defect density and stress are concentrated. Lacking grain boundaries, single crystals exhibit lower defect density, higher carrier mobility and longer carrier lifetime, thus benefiting longer carrier diffusion length. However, the large thickness of single crystals is not conducive to direct extraction of carriers out of photoelectric devices because the carrier diffusion length is within dozens of micrometers. Therefore, ultrathin single crystal films (SCFs) are demanded for photoelectric devices. In this paper, we put forward an improved space confined method, in which the nucleation and growth processes are controlled through altering the heating area. A series of MAPbBr3 SCFs with maximum size over 30 mm and controllable thickness (15–45 μm) are obtained. The growth kinetics of MAPbBr3 SCFs are analyzed in detail. Owing to the controllable growth kinetics, MAPbBr3 SCFs possess higher crystallinity, higher photo-induced carrier densities and longer carrier lifetimes than the corresponding bulk single crystals (BSCs). Therefore, MAPbBr3 SCFs exhibit better optoelectronic performance and device stability as planar photo-detectors, such as lower dark currents and higher photo-currents, higher R and EQE values and higher on/off ratios.
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产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Xiaoqing Wu,Cheng Che,Xinmeng Wang,Qiujiao Du,Huageng Liang,Pengcheng Gao,Fan Xia
DNA species are recognized as a powerful probe for nanochannel analyses to address the issues of specific target recognition and highly efficient signal conversion due to their programmable and predictable Watson–Crick bases. However, in the conventional view, abundant sophisticated DNA structures synthesized by DNA amplification strategies are unsuitable for use in nanochannel analyses owing to their low probability to enter a nanochannel restricted by the smaller opening of the nanochannel, as well as the faint ion signal produced by the steric effect. Here, we present an integrated strategy of nanochannel analyses that combines the target recognitions by encoded rolling circle amplification (RCA) in solution and the ionic signal enhancement by the space charge effect through the immobilization of highly negative-charged RCA amplicons on the outer surface of the nanochannels. Owing to the highly negative-charged RCA amplicons with 100 nm sizes, a sharp increase of ionic current up to 7454% has been achieved. The RCA amplicon triggered by mRNA-21 on the outer surface of the poly(ethylene terephthalate) membrane with a single nanochannel realized the single-base mismatch detection of mRNA-21 with a sensitivity of 6 fM. The DNA amplicon endows the nanochannel with high sensitivity and selectivity that could extend to other applications, such as DNA sequencing, desalination, sieving, and water–energy nexus.
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Feng Wu,Yu Huang,Xian Yang,Jing-Jing Hu,Xiaoding Lou,Fan Xia,Yanlin Song,Lei Jiang
Determining the expression level of biomarkers is crucial for disease diagnosis. However, the low abundance of biomarkers in the early stage makes the detection extremely difficult by traditional aggregation-induced emission (AIE)-based fluorescent probes. Here, by tuning the intermolecular interaction, a two steps-based MP/NPs-SLIPS sensing system is designed for ultrasensitive detection of the tumor marker matrix metalloproteinase-2 (MMP-2). During the sensing process, aggregation of AIE residual could be intensified through the electrostatic absorption by negatively charged nanoparticles (NPs), as well as the confined space formed by the self-assembly of NPs to photonic crystals (PCs) on slippery lubricant-infused porous substrates (SLIPS). The fluorescent signals obviously increased with a strengthened aggregation degree, which contributes to improved sensitivity. Thus, the limit of detection is decreased to 3.7 ng/mL for MP/NPs-SLIPS sensing system, which could be used for detecting the MMP-2 secreted by tumor cells directly. This strategy also demonstrated its potential applications as high-throughput detection devices and will be of significance for the ultrasensitive analysis of biomarkers.
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产品关联
DOI
PubMed
高影响因子
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