INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2018
·
IF 4.229
Chenyi Wang,Yuanpeng Zhou,Chang Xu,Xiaoyan Zhao,Jian Li,Qiang Ren
In order to enhance the properties of polymer anion-exchange membranes (AEMs), a class of side-chain-type poly (arylene ether sulfone)s containing tri-imidazole cations in pendant phenoxyphenyl spacer (i.e., Im-PES-xx) were designed and prepared by polymer grafting reaction. Based on these imidazole functionalized polymers, a series of new AEMs were successfully prepared by their solution coating and ion exchange. The obtained membranes exhibited good alkaline stability with the retention of ion-exchange capacity in the range of 78.5%–83.3% after immersion in 4 M NaOH solution at 80 °C for 336 h. The membranes also had high hydroxide conductivity with the values of 34.1–70.5 mS cm −1 at 80 °C. Meanwhile, these membranes possessed good dimensional stability, and their swelling ratio was in the range of 2.5%–7.0% at 80 °C. The incorporation of the dense and local imidazole cations in the side chains for AEMs plays an important role for their properties.
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高影响因子
Nanoscale
·
2018
·Vol. 10
·期 32
·15238-15248
·
IF 7.233
Qijun Che,Ningning Bai,Qing Li,Xinhong Chen,Ya Tan,Xi Xu
An enormous challenge in the development of renewable hydrogen sources for electricity-driven water-splitting systems has been the limitation of the earth-abundant and robust highly-active cathode electrocatalysts. In this work, we developed a simple sulfur-anion doping strategy to obtain the S-doped NiCo composite (S-NiCo@50) on Ni foam (NF) via a one-step electrochemical deposition. It was found that doped sulfur plays a crucial role in reducing the overpotential of hydrogen evolution by providing abundant active sites as identified by the XPS spectrum. The formed metallic Ni and Co effectively promoted electron transportation. The synergistic effects between the amorphous CoxNiyS(x+y) substance and crystalline Ni and Co metal seemed to result in enhanced HER activity. In particular, the S-NiCo@50 electrode, featuring a hierarchical morphology, showed an ultralow overpotential of 28 and 125 mV at 10 and 100 mA cm−2, respectively, in 1.0 M NaOH with a large exchange current density (j0) of 4.8 mA cm−2 as well as high conductivity and stability; its catalytic properties are superior to most of the reported alkaline electrocatalysts and are on par with commercial Pt/C. Assembled with the counter electrode (Ni–Fe/NF), the overall water splitting was proved with a low 1.55 V at 10 mA cm−2. Moreover, we built the Ni24Co6S6 cluster as the S-NiCo@50 model and revealed its intrinsic activity by density functional theory (DFT) calculations. This study shows that S-doping and component control can be an exquisite strategy for realizing high-efficiency electrochemical water reduction.
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PubMed
高影响因子
ACS Applied Nano Materials
·
2018
·
IF 0
Kai Yang,Lei Zhong,Jiaxiang Qin,Junchen Liu,Min Xiao,Dongmei Han,Shan Ren,Luyi Sun,Shuanjin Wang,Yuezhong Meng
The high theoretical specific capacity of lithium–sulfur battery is regarded as a promising candidate for next-generation battery systems. However, “polysulfide shuttle” is known as a major issue of accelerating capacity fading and corroding the metal lithium anode, which impedes its commercial application. Here, a nitrogen–sulfur codoped two-dimensional carbon material is synthesized using a novel template method by pyrolyzing chemical adsorption of montmorillonite and methylene blue. The microstructure and morphologies of the synthesized two-dimensional carbon materials are fully characterized using SEM, TEM, XRD, and Raman techniques. The experiment results indicate that the carbon material shows a typical graphene structure. The micro/mesoporous and heteroatoms codoped structure of the synthesized carbon material exhibits excellent performance in electronic conductivity and polysulfides confinement. The functional separator laminated with the binder-free carbon material endows the battery outstanding electrochemical and rate performances. The excellent rate performance is discovered a capacity of 828 mAh g–1 at 4 C with good reversibility. The battery presents a high initial discharge specific capacity of 1049 mAh g–1 with good capacity retention of 690 mAh g–1 after 500 cycles at 1 C. Consequently, the separator laminated with the nitrogen–sulfur codoped graphene is promising for the construction of high performance Li–S batteries.
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SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Mingxia Jiao,Yun Li,Yuxiu Jia,Zhen Yang,Xiliang Luo
Non-cadimum photoluminescent I−III−VI semiconductor nanocrystals have attracted increasing attention due to their low toxicity, extraordinary optical and electronic properties. Herein, water-soluble quaternary Cu-In-Zn-S quantum dots (CIZS QDs) with tunable emission from 535 nm to 645 nm were successfully synthesized via ecofriendly one-pot aqueous method. The full width at half-maximum (FWHM) of the emissions are about 68 nm–88 nm, which are rather narrow among Cu-based semiconductors and preferred to facilitate improving color purity. The photoluminescence of water-soluble QDs was enhanced by ZnS coating with the absolute quantum yield (QY) up to 30.8%. Further, a novel fluorescent sensor for Cu 2+ detection was developed based on the alteration of intrinsic optical properties of the CIZS/ZnS QDs after cation exchange at room temperature within 10 min, presenting a linear range of 0.020–20 μM and a detection limit down to 6.7 nM. Mechanism studies revealed that the QDs served as the template for cation exchange, through UV–vis absorption and fluorescence spectra in combination with the chemical composition and time-resolved photoluminescence decay analysis. Ions interference experiments demonstrated the good selectivity of the QDs towards Cu 2+ and the sensor showed comparable accuracy to ICP-AES method as well as good performance in real sample detection, manifesting the reliability of the current strategy for sensing Cu 2+ mildly and rapidly.
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高影响因子
JOURNAL OF LUMINESCENCE
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2018
·
IF 2.732
Ze Min Hu,Guang Tao Fei,Li De Zhang
The Cu-Ga-S/ZnS quantum dots (QDs) emitting green-to-red light are successfully synthesized by the conventional hot-injection method. In the preparation process, 1-dodecanethiol (DDT) is not only used as the solvent but also the sulfur precursor and ligand. Therefore, all reactants are additives, which can reduce solution contamination. The peak wavelength of Cu-Ga-S/ZnS QDs' emission can be tuned from 520 to 619 nm by changing Cu/Ga stoichiometry . And these quantum dots have narrow full-width at half maximum wavelength of about 75 nm. Furthermore, a white quantum-dot-based light-emitting diode is obtained by depositing the yellow Cu-Ga-S QDs on a blue InGaN chip.
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高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 38
·18649-18659
·
IF 9.931
Zheming Liu,Aiwei Tang,Jun Liu,Dongxu Zhu,Xifeng Shi,Qinghua Kong,Zhijie Wang,Shengchun Qu,Feng Teng,Zhanguo Wang
Multinary copper-based chalcogenides have been exploited in photocatalytic hydrogen generation due to their exceptional visible light absorption properties and environmentally friendly character. Similar to other photocatalysts, to reinforce the charge separation and transfer is one of the most important pathways to enhance photocatalytic hydrogen evolution, which can be achieved by rationally designing the nanostructures and geometries of multinary copper-based chalcogenides. Herein, an improved photocatalytic hydrogen evolution is successfully realized in L-shaped Cu–Ga–Zn–S (CGZS) alloyed nanorods compared with the binary Cu31S16 and ternary CuGaS2 nanocrystals. The L-shaped wurtzite CGZS nanorods with a uniform spatial composition distribution are synthesized via a non-injection solution approach for the first time. The successive incorporation of zinc and gallium ions into Cu31S16 seeds leads to formation of Cu31S16–ZnS and Cu31S16–CGZS heteronanostructures and finally results in the formation of single phase CGZS nanorods. The intrinsic features of L-shaped wurtzite CGZS nanorods offer efficient spatial charge separation and electrical transport, which contribute synergistically to the improved photocatalytic activity. This study provides a new way to develop novel multinary copper-based chalcogenides with flexible nanostructures for efficient photocatalytic hydrogen production.
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高影响因子
APPLIED SURFACE SCIENCE
·
2014
·
IF 2.538
Zhiyin Chao,Lan Wang,Linyong Song,Yifeng Zhou,Wangyan Nie,Pengpeng Chen
Surface hydroxyl-functionalized poly(styrene- co -hydroxyethyl acrylate) [P( S - co -HEA)] microsphere were used to prepare P( S - co -HEA)/silver composite particles. Based on the weak interaction between silver ions and hydroxyl, silver ions were adsorbed onto the polymer surface and reduced by diethanolamine (DEA). The morphology of P( S - co -HEA)/Ag was easily controlled by the molar ratio of DEA/AgNO 3 . The composite particles were characterized by SEM, XRD, and UV–vis spectroscopy. The obtained P( S - co -HEA)/Ag particles with small and denser silver nanoparticles showed a high efficient activity to catalyze reduction of methylene blue (MB). While the P( S - co -HEA)/Ag particles with big and denser silver nanoparticles showed highly sensitive Raman enhanced performance.
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高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
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2015
·Vol. 17
·期 10
·1-11
·
IF 2.184
Hu Nan,Li Rui,Wu Zhao-liang,Huang Di,Li Hong Zhen
Foam flotation is a promising technique for recovering nanoparticles from their highly diluted suspensions. In this work, a novel S type internal was developed to intensify the foam flotation of CuO nanoparticles (357.6 nm in average particle size) from their suspension of 6.2 × 10 −2 mmol/L. By enhancing foam drainage, the S type internal increased the enrichment ratio of CuO nanoparticles by 139.3 ± 12.5 % without significantly affecting their recovery percentage. Under the optimal conditions of Cetyl trimethyl ammonium bromide (CTAB) concentration 0.45 mmol/L, superficial airflow rate 2.6 mm/s, and volumetric feed rate 1.0 mL/min, the enrichment ratio and recovery percentage of CuO nanoparticles reached 81.6 ± 4.1 and 95.4 ± 4.9 %, respectively, using the foam flotation column with the S type internal. Furthermore, about 95 % CTAB could be recycled by recovering CTAB from the foamate and the residual solution. The recovered CuO nanoparticles were associated with CTAB molecules, so they had better dispersity and dispersion stability than the starting CuO nanoparticles. Therefore, they would have good reusability.
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高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 40
·20244-20253
·
IF 7.443
Gui-lin Zhuang,Jia-qi Bai,Xin-yong Tao,Jian-min Luo,Xin-de Wang,Yi-fen Gao,Xing Zhong,Xiao-nian Li,Jian-guo Wang
S,N-co-doped porous carbon (SNPC) materials are good candidates for the cathodic oxygen-reduction reaction (ORR) and lithium-ion batteries (LIBs). However, SNPC gives low yield and is expensive. Herein, we report a new and efficient method for synthesizing a S,N-co-doped mesoporous carbon material through the carbonization of S,N-containing precursors in molten ZnCl2, where ZnCl2 served as the ionic solvent and Lewis acid catalyst. The resultant SNPC-800 showed a mesoporous structure with a specific surface area of 1235 m2 g−1 and a mesopore-size range of 10–45 nm, which were considerably larger than those obtained through the carbonization of ionic liquids and fabrication of graphene oxides. Furthermore, ORR measurements indicated good catalytic activity, comparable to the commercial Pt/C catalyst. Also the SNPC-800 material exhibited excellent catalytic stability, and high methanol tolerance compared to the commercial Pt/C catalyst. Density functional theory calculation results revealed that the catalytic properties originated from the synergistic effect of the S/N dopant and that the main catalytic reaction path followed an associative mechanism. LIB tests further showed high reversible capacity, as well as excellent cycling stability and rate performance.
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高影响因子
CHEMISTRY OF MATERIALS
·
2013
·
IF 8.238
Shuijin Lei,Chunying Wang,Lei Liu,Donghai Guo,Chuanning Wang,Qingliu Tang,Baochang Cheng,Yanhe Xiao,Lang Zhou
Group I–III–VI ternary chalcogenides have attracted extensive attention as important functional semiconductors. Among them, Cu–In–S compounds have seen strong research interest due to their potential applications in high-efficiency solar cells. However, the controllable synthesis of Cu–In–S nanostructures with different phases is always difficult. In this research, zinc-blende CuInS2, wurtzite CuInS2, and spinel CuIn5S8 could be selectively synthesized using spinel In3–xS4 as the precursor by a simple solvothermal method. X-ray powder diffraction was used to determine the phase and crystal structure, and transmission electron microscopy was employed to characterize the morphologies of the as-prepared samples. Experiments showed that the acidity–basicity of the reaction system and the coordination and reducibility of the capping ligands were crucial to the final phases of the products. The UV–vis–NIR spectra of the three phases all exhibited a broad-band absorption over the entire visible light and extending into the near-infrared region, and the zinc-blende, wurtzite, and spinel Cu–In–S nanocrystals showed band gaps of 1.55, 1.54, and 1.51 eV, respectively, which indicates their potential applications in thin-film solar cells.
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高影响因子
RSC Advances
·
2014
·Vol. 5
·期 6
·4184-4190
·
IF 3.708
Qingwen Tian,Yong Cui,Gang Wang,Daocheng Pan
The metal chalcogenides are excellent choices as absorbers and buffer-layers in thin film solar cells. Versatile chemical approaches provide endless possibilities to prepare metal sulfide precursor solutions. Recently, Cu2ZnSnS(Se)4 thin films have played an important role in fabricating low-cost and high-efficiency solar cells. Here, we present a robust and low-cost 1,2-ethanedithiol/ethanolamine/2-methoxyethanol ternary solution process to prepare Cu2ZnSnS4 precursor solution and high-quality Cu2ZnSnS4 thin films. Low-cost Cu2O, ZnO and SnO are used as the raw materials, which can be easily dissolved in the 2-methoxyethanol solution of 1,2-ethanedithiol and ethanolamine at room temperature in air. By tuning the composition of the Cu2ZnSn(S,Se)4 thin film with a selenization process, an active-area power conversion efficiency of 7.34% has been achieved for Cu2ZnSn(S,Se)4 solar cell.
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高影响因子
POLYMER COMPOSITES
·
2016
·Vol. 39
·期 1
·126-134
·
IF 2.004
Chunhua Lai,Junjie Li,Xiongzhi Xiang,Lei Wang,Danqing Liu
A series of conjugated poly(3,4-ethylenedioxythiophene methine)s (PEDOT-Ms) with different side groups (e.g., electron-withdrawing, electron-donating, and electron-neutralizing groups) containing 3,4-ethylenedioxythiophene (EDOT) units was synthesized and characterized, showing low optical bandgaps. Then, the PEDOT-M polymers were blended with graphite (G) to prepare polymer–inorganic composites to compare their thermoelectric (TE) properties. The optical absorption study indicated direct bandgaps ranging from 1.72 to 1.79 eV. The results showed that PEDOT-M polymers with strongly electron-withdrawing and electron-donating groups exhibited lower bandgap values and higher Seebeck coefficients, and their composites exhibited better TE properties than PEDOT-M with an electron-neutralizing side group. The highest figure of merit (ZT) value for the (poly[{3,4-ethylenedioxythiophene-2,5-diyl} { p -nitrobenzylidene}{3,4-ethylenedioxythiophenequinodimethane-2,5-diyl}])(PEDOT-NBQ)/80 wt% G composite was 6.75 × 10 −3 at 120°C, which was higher than the ZT value of the other PEDOT-M/G composites. These results reveal a novel approach using the structural modifications of polymers to improve the understanding of TE performance and confirm that the conjugated PEDOT-M samples studied are low-bandgap conducting polymers that can be used as TE materials. POLYM. COMPOS., 39:126–134, 2018. © 2016 Society of Plastics Engineers
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高影响因子
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