Journal of Environmental Sciences
·
2024
·
IF 5.9
Xixian Huang,Bing Yang,Ye Dou,Yang Ding
The abiotic oxidation of divalent manganese (Mn(II)) and the formation of Mn oxides are important geochemical processes, which control the mobility and availability of Mn as well as element cycling and pollutant behavior in soils. It was found that iron (oxyhydr)oxides can catalyze Mn(II) oxidation , but the effects of the coexisting dissolved organic matter (DOM) molecules on the catalysis of different iron (oxyhydr)oxides for Mn(II) oxidation are poorly understood. Herein, we investigated Mn(II) oxidation under the impacts of the interactions between iron (oxyhydr)oxides (i.e., ferrihydrite, goethite and hematite) and DOM molecules. Simultaneously, we elucidated the variations of DOM composition and properties. Our results indicated that the catalysis of iron (oxyhydr)oxides for Mn(II) oxidation was significantly inhibited by DOM. Moreover, DOM had less inhibiting effect on the catalysis of ferrihydrite for Mn(II) oxidation and the formation of Mn oxides (e.g., hausmannite and buserite) relative to goethite and hematite, which was partially because of the higher electron transfer capacities of ferrihydrite. Meanwhile, DOM molecules with high nominal oxidation state of carbon (NOSC), molecular weight, unsaturation and aromaticity were selectively adsorbed and oxidized by Mn oxides , including the oxygenated phenols and polyphenols. The newly formed molecules mainly belonged to phenols depleted of oxygen and aliphatics. Furthermore, NOSC was a key molecular characteristic for controlling DOM composition during DOM adsorption and oxidation by Mn oxides when iron minerals were present. Overall, our research contributes to understanding Mn(II) oxidation mechanisms under heterogeneous systems and behaviors of DOM molecules in the environment.
研究领域:
环境地球化学
·
土壤化学
·
水文地球化学
·
有机-矿物相互作用
·
元素生物地球化学循环
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Shuya Wang,Yaxin Chen,Bin Cui,Bo Li,Shuxuan Wang,Yanhua Cui,Zhicheng Ju,Quanchao Zhuang
Computer simulation accelerates the selection and application of new electrode materials. The First-principles calculations based on density functional theory (DFT) are performed to evaluate the performance as cathode for Potassium ion batteries (PIBs) on the structure, electronic conductivity and ionic diffusion of O-doped KMnF 3 . After taking comprehensive consideration of the calculation results, the nanostructured O-doped KMnF 3 was synthesized and the structure and electrochemical properties were further improved by carbon coating. Here, we report a new etch pathway to create a new class of carbon-coated perovskite fluoride to improve the performance of PIB in terms of rate capability and cycle stability. These new material design concepts will help discover and synthesize new materials for PIBs.
研究领域:
材料科学
·
电化学
·
计算材料学
·
能源存储
·
无机化学
·
纳米材料
·
固体物理
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2020
·
IF 2.726
Qian-Ting Xu,Wen-Dong Yao,Xiao-Hui Li,Sheng-Ping Guo
Metal chalcogenides are extensively studied as infrared second-order nonlinear optical (NLO) materials. Among the candidates, ones containing cations with lone-pair electrons in the structure have received great interest in view of the lone-pair electrons’ special contribution to the NLO property . Here, we revisit such a sulfide Sb 6 Sb 6 S 17 and study its NLO property , which represents a novel structure-type of NLO material. It exhibits phase-matchable second-harmonic generation activity, and the powder sample shows a laser-induced damage threshold (LIDT) around 3.2 times that of AgGaS 2 when both have the particle sizes of 75–110 μ m. Its optical energy gap is measured to be 1.92 eV and the powder sample has a transparency range from 0.65 to 25 μ m. The electronic structure and optical property calculations are also performed.
研究领域:
材料科学
·
凝聚态物理
·
无机化学
·
光学材料
·
固体化学
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 9
·2313-2320
·
IF 2.162
Hui Zhao,Si-Qi Zhao,Guo-Hua Hu,Qun-Chao Zhang,Yang Liu,Chong-Xing Huang,Wei Li,Tao Jiang,Shuang-Fei Wang
A facile method was developed to synthesize a new type of polyhedral oligomeric silsesquioxane (POSS). It contained a single amine group and seven aliphatic moieties on its corners. FT-IR, 1 H-NMR, 13 C-NMR, 13 C- 1 H COSY, and 1 H- 1 H COSY confirmed that cages with eight corners were the main part of the product. This new POSS was used to modify the structure of hexamethylene diisocyanate trimer and then copolymerized with hexamethylene diisocyanate and poly (tetramethylene glycol) to get a serious of waterborne polyurethane (WPU)/POSS hybrid materials with low dielectric constants for microelectronics applications. The results showed that POSS particles were uniformly dispersed in the WPU dispersions. The WPU/POSS films did not show any macrophase separation, even when the POSS content was as high as 16%. As the POSS content increased from 0% to 16%, the tensile strength was increased from 2.3 to 7.3 MPa, the dielectric constant was decreased from about 2.9 to 2.0, and the thermal stability of the WPU/POSS was also improved.
研究领域:
高分子科学
·
材料化学
·
纳米复合材料
·
电子封装材料
·
功能高分子
✓ 已验证
DOI
高影响因子
THIN SOLID FILMS
·
2018
·
IF 1.939
Yanqi Lv,Yanhong Li,Hongxia Sun,Yi Guo,Yanmei Li,Jinkun Tan,Xingfu Zhou
Crystalline yttrium-doped rutile TiO 2 nanorod arrays were synthesized and successfully implemented as a photoanode of perovskite solar cells . Study shows that yttrium was successfully doped and TiO 2 band gap changes from 3.07 eV to 3.02 eV. A positive shift of 100 mV in the flat-band potential (V fb ) was observed in Y-doped rutile TiO 2 nanorods. A power conversion efficiency of 7.95% and a photocurrent density of 15.13 mA/cm 2 were obtained for the doped sample. The photocurrent density is 1.47 times higher than that of the un-doped device. Incident photon-to-current conversion efficiency shows Y-doped device has a clear increase in quantum efficiency in the visible light range from 450 and 750 nm. Open circuit voltage decay measurements demonstrate the superior ability of Y-doped TiO 2 nanorod for separating electrons and holes and decreasing the recombination events. The improved performance is possibly attributed to the enhanced electron injection and transfer efficiency caused by a positive shift in V fb and a reduction in charge recombination. This study opens a door toward the improvement of photocurrent density of perovskite solar cell via an element doping route.
研究领域:
材料科学
·
纳米科技
·
能源化学
·
光电子学
·
半导体物理
·
可再生能源
✓ 已验证
DOI
高影响因子
Materials Today Physics
·
2023
·
IF 11.5
Ruifan Si,Zhongwei Zhang,Chengyan Liu,Ying Peng,Xiaobo Bai,Baoquan Feng,Junliang Chen,Jie Gao,Lei Miao
With developing of thermoelectric (TE) performance, GeTe-based TE materials present great promising application at medium temperatures as a replacement for toxic PbTe. However, the further improvement of TE properties is severely constrained by the coupling of electron and phonon transport. In this study, we achieve decoupled electron and phonon transport by effectively creating a special phase boundary to scatter phonon but transmit electron by implanting multi-walled carbon nanotubes (MWCNTs) into Bi-doped GeTe. With the help of this decoupling mechanism, the power factor is effectively improved and reaches up to ∼4482 μW −1 m −1 K −2 at 673 K while the thermal conductivity shows an obvious drop to ∼1.27 W m −1 K −1 at 723 K, leading to an impressive increase in zT to a maximum value of ∼2.3 at 723 K. In particular, a competitive average zT value of ∼1.43 in the temperature range of 323–773 K is obtained, which is at a high level in lead-free GeTe-based materials. Our method could be used as a guidance for the decoupling of electron and phonon transport in other TE materials .
研究领域:
材料科学
·
凝聚态物理
·
能源材料
·
热电转换
·
纳米复合材料
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2021
·Vol. 64
·期 6
·1378-1385
·
IF 8.273
Fu Yuanyuan,Ma Cheng
The interplay between solid electrolytes and electrodes is of vital importance to the performance of all-solid-state Li batteries. Recently, halide superionic conductors have emerged as a new family of high-performance solid electrolytes, but their compatibility with Li metal, i.e., the anode with the highest theoretical capacity, has not been systematically studied. Here, we investigate the interaction between Li metal and two representative halide solid electrolytes: Li 3 YCl 6 and Li 3 YBr 6 . Both materials are found to form interphases with Li, similar to most solid electrolytes. However, the interphases observed here contain electronic conducting components, which are detrimental to their compatibility with Li. By elucidating this phenomenon, the present study provides guiding principles for improving the Li compatibility of halide solid electrolytes.
研究领域:
材料科学
·
电化学
·
固态离子学
·
能源存储
·
电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2018
·
IF 2.179
Linlin Xu,Dong Chen,Hui Liu,Jun Yang
Structural conversion using core-shell silver (Ag)-platinum (Pt) nanoparticles as starting materials is a promising way to produce nanocomposites consisting of silver sulfide (Ag 2 S) and hollow Pt nanostructures (Ag 2 S-hPtNCs). However, the mechanism behind the structural conversion process is yet to be understood. In this study, we use transmission electron microscope (TEM) as a typical tool to characterize the products formed in different structural conversion processes, and interpret the experimental observations by proposing mechanisms behind the reactions between core-shell Ag-Pt nanoparticles and sulfur precursors from different sources. We then design additional experiments to rationalize the formation mechanism we proposed. The mechanistic understanding of the structural conversion from bimetallic core-shell nanostructures to heterogeneous nanocomposites may extend the fabrication of heterogeneous nanocomposites for a given technological application.
研究领域:
纳米材料科学
·
无机化学
·
纳米医学
·
生物材料
·
转化医学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2013
·Vol. 51
·期 7
·1559-1564
·
IF 3.543
Xiao-Hui Liu,Yun-Hai Yu,Di Jia,Bo-Wen Cheng,Fei-Jun Zhang,Hui-Na Li,Peng Chen,Shan Xie
Single electron transfer living radical polymerization of methyl methacrylate catalyzed by the in situ prepared Cu(0) at ambient temperature was first examined using various metallic powders, including Zn(0), Ni(0), Mg(0), and Fe(0). Importantly, the polymerization initiated with Ni(0)/EBiB/CuBr 2 /PMDETA system exhibited optimal living/controlled nature and generated polymers with polydispersity index as low as 1.04 for 75.27% conversion and controlled molecular weights close to theoretical ones. A wide of range of Cu(II) salts were also investigated as catalyst sources instead of CuBr 2 . The recycling of Ni(0) was very convenient due to its magnetic property, which enables its extensive application. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
研究领域:
高分子化学
·
材料科学
·
催化化学
·
有机合成
·
功能材料
✓ 已验证
DOI
高影响因子
PHYSICA B-CONDENSED MATTER
·
2022
·
IF 2.988
Wei Zhang,Zhiwei Gu,Bingbing Zong,Yueju Fu,Kai Zhang,Yubao Li
Defects is of special importance in tuning the structure and physical properties of layered materials. Here the influence of transition metal Co vacancies on the structure and magnetism in collapsed tetragonal CaCo 2- x As 2 (0 ≤ x ≤ 0.3) solid solutions are systematically investigated. The electrical properties show metallicity in all compounds. The crystal structure refinement exhibits that the lattice constant of the c axis and c / a ratio decreases as Co vacancies increase, revealing the formation of a more collapsed tetragonal structure in CaCo 2- x As 2 . Moreover, these introduced Co vacancies suppress the antiferromagnetic Néel temperature from 80 K down to 18 K until it disappears above 10 K in CaCo 1 · 7 As 2 . X-ray photoelectron spectroscopy reveals increased Co 3+ /Co 2+ value in CaCo 2- x As 2 with higher Co vacancies, which may result in the charge balance and the gradually suppressed T N . This study offers insights into tuning and understanding the magneto-structural characteristics in ThCr 2 Si 2 -type layered materials through transition metal vacancies.
研究领域:
凝聚态物理
·
材料科学
·
固体化学
·
磁学
·
晶体工程
·
缺陷工程
✓ 已验证
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Boru Du,Jingyu Lu,Guantao Wang,Mingguang Han,Yan Gao,Sida Luo
Laser-induced graphene (LIG) is a highly promising technology for assembling thin-film electronics with miniaturized surficial patterns, although hard to guarantee both high-quality formation of raw materials and high resolution of feature size. In this study, a combined microcontact printing (μCP) and LIG protocol is creatively utilized to fabricate ultra-thin graphene films with highly ordered micro-stripe arrays. In addition to realize various patterned structures with unique scalable and stackable characteristics, PAA concentration (4–8 wt%) is systematically investigated as a critical parameter to precisely control the feature size of micro-patterns before and after the irradiation process, including line width (before: 5.37–22.44 μm, after: 4.83–22.32 μm) and average height (before: 69.81–187.39 nm, after: 5.72–48.61 nm). By further exploring a defocused multi-lasing strategy, sheet resistance of the graphene array could be optimized dramatically from 634.1 kΩ/sq to 1.9 kΩ/sq, while maintaining low ablation (45.38 % porosity) and high carbon content (84.2 wt%). Lastly, the process is demonstrated to assemble different graphene based electronic devices with miniaturized sizes, including liquid sensors with sensitivity of 2.7 % μL −1 and electrothermal heaters with temperature-ramping rate as high as 24.7 °C/s and working temperature as high as 248 °C.
研究领域:
材料科学
·
纳米科技
·
电子工程
·
生物医学工程
·
表面科学
·
柔性电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 20
·
IF 1.768
Yaobin Liu,Zhiqiang Fan
Two tribromide compounds, 1,3-(propanoic acid, 2-bromo-)-2-(2-bromo-1-oxopropylamino)propyl ester (A 1 ) and trimethylolpropane tris(2-bromopropionate) (A 2 ), were synthesized. By Cu/ N,N,N′,N′,N″ -pentamethyldiethylenetriamine (PMDETA)-mediated radical addition-coupling polymerization (RACP) of 2-methyl-2-nitrosopropane (MNP) with the tribromide compounds, two types of hyperbranched polymers were synthesized under mild conditions, respectively. Polymerization degrees of the polymers increased with time gradually, which is in line with a step-growth polymerization mechanism. By tracing the polymerization process by gel permeation chromatography and NMR analysis, proper reaction conditions to get hyperbranched polymers was obtained. Based on the results of NMR analysis on the polymer chain structure, mechanism of forming hyperbranched polymer has been proposed, which includes formation of carbon radicals from the tribromo monomer through single electron transfer, their reaction with MNP to form nitroxide radicals, and cross-coupling reaction of the nitroxide radicals with other carbon radicals. The gelation point of the A 2 -MNP system is larger than that of the A 1 -MNP system, indicating that probability of intramolecular cyclization in A 2 -MNP RACP system is higher than the A 1 -MNP system. The reactivity of —NHCOCH(CH 3 )Br group of A 1 is lower than its two —OCOCH(CH 3 )Br groups, and this resulted in longer distance between two adjacent branch points in the hyperbranched polymer of A 1 -MNP than the A 2 -MNP system. It is possible to adjust the chain structure of RACP-based hyperbranched polymer by changing the reactivity of the functional groups in A 3 monomer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41972.
研究领域:
高分子化学
·
聚合物合成
·
功能高分子
·
材料化学
·
有机合成方法学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）