Environmental Science-Nano
·
2023
·Vol. 10
·期 5
·1220-1231
·
IF 7.3
Shishu Zhu,Yijun Mo,Wendan Luo,Zihan Xiao,Chao Jin,Rongliang Qiu
Soil dissolved organic matter (SDOM) forms the corona and affects the colloidal mobility of Cr (hydr)oxides. Such processes are important in evaluating Cr immobilization effectiveness. This study for the first time found that the SDOM composition instead of electrostatic interactions accounted for the significant differences in the aggregation and deposition kinetics of short-range-order Cr(OH)3 Cr(OH)3 and crystalline Cr2O3. The molecular-scale composition of SDOM associated with Cr (hydr)oxides was investigated using Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS) and Fourier transform-infrared spectroscopy (FT-IR). Low molecular-weight aromatic compounds with multiple carboxyl groups and amphiphilic segments preferentially associated with Cr(OH)3, whereas Cr2O3 mainly adsorbed high molecular-weight hydrophobic compounds. The molecular composition of SDOM associated with colloids depended on the singly coordinated hydroxyl content of Cr (hydr)oxides. The aggregation and deposition of Cr(OH)3 significantly increased with increasing SDOM loading due to the formation of more thermodynamically stable coprecipitates in solution or on the silica surface via bridging of carboxylates. A secondary zonal layer on Cr(OH)3 inhibited the coprecipitation of Cr(OH)3 with SDOM under a high SDOM loading. In contrast, the aggregation and deposition of Cr2O3 decreased with increasing SDOM loading due to the steric hindrance of hydrophobic compounds. This study highlighted the importance of corona composition in assessing the potential mobility of Cr (hydr)oxides and the stability of immobilized Cr species.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 12
·1-10
·
IF 5.479
Huang Shan,Yang Erli,Yao Jiandong,Chu Xu,Liu Yi,Xiao Qi
A rapid, sensitive, and selective fluorometric assay is described for the determination of chromium(VI) in real waters and living cells. The method is making use of nitrogen, phosphorus, and sulfur tri-doped carbon dots (NPS-CDs) which have absorption/emission maxima at 360/505 nm/nm. Cr(VI) has an absorption maximum at 350 nm and causes an inner filter effect (IFE) on the blue fluorescence of the NPS-CDs. The NPS-CDs were hydrothermally synthesized using p -aminobenzenesulfonic acid and tetrakis(hydroxymethyl)phosphonium chloride as precursors. The NPS-CDs were characterized by transmission electron microscopy, X-ray diffraction, and several spectroscopic methods. They are biocompatible and negligibly cytotoxic when tested with HeLa cells and MCF-7 cells even after 48 h of incubation. The NPS-CDs were used as fluorescent probes for Cr(VI). The detection limit is 0.23 μM (three times standard deviation versus slope), and the linear response covers the 1 to 500 μM chromate concentration range. The NPS-CDs were applied to the determination of Cr(VI) in real waters and living cells (HeLa and MCF-7) and gave satisfying results.
Schematic representation of hydrothermal synthesis of nitrogen, phosphorus, and sulfur tri-doped carbon dots (NPS-CDs) for Cr(VI) detection via inner filter effect (IFE). NPS-CDs were applied to the determination of Cr(VI) in living cells (HeLa and MCF-7) with satisfying results.
研究领域:
分析化学
·
环境科学
·
生物医学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF SURFACTANTS AND DETERGENTS
·
2020
·Vol. 23
·期 5
·981-989
·
IF 1.654
Xihuai Qiang,Ting Jian,Wei Xu
A series of polyethylene glycol-linked Gemini fatty alcohol phosphate surfactants (GFAP) were prepared with long chain n -alkanol (C = 8, 12, 16, 18), polyethylene glycol (PEG-200, PEG-400, PEG-600, PEG-800, PEG-1000) and phosphorus oxychloride (POCl 3 ). The structure of the prepared surfactants was characterized by Fourier transform infrared spectrometer (FT-IR). The surfactants were employed for the modification of chrome-tanned leather. The morphological changes of chrome-tanned leather and modified chrome-tanned leather were observed by scanning electron microscopy (SEM). The relationship between the alkyl chain length and molecular weight of the PEG and the hydrophobicity, softness, mechanical strength of modified chrome-tanned leather was also discussed. The experimental results showed that the mechanical strength and softness of modified chrome-tanned leather were enhanced with an increase of alkyl chain length, while the hydrophobicity, mechanical strength and softness were decreased with an increase of molecular weight of the PEG. The hydrophobicity, mechanical strength and softness of modified chrome-tanned leather were optimized for an alkyl chain length of 16. Therefore, 16–200 Gemini phosphate surfactants with an alkyl chain length of 16 and a PEG molecular weight of 200 have a good comprehensive modification effect on Chrome-tanned leather, the tensile strength, tear strength and softness of modified chrome-tanned leather are 57.07 N mm −2 , 79.49 N mm −1 , 9.73 mm, respectively.
研究领域:
化学工程
·
材料科学
·
皮革加工技术
✓ 已验证
DOI
高影响因子
Micro & Nano Letters
·
2017
·Vol. 12
·期 12
·1020-1023
·
IF 0.723
Feifan Xu,Gang Cheng,Yi Wei,Rong Chen
BiOCl/Bi 2 S 3 hollow hybrids were synthesised through a mild anion-exchange method from BiOCl microspheres and thiacetamide. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption measurements, ultraviolet–visible–near-infrared diffuse reflectance spectra, photocurrent, and electrochemical impedance spectroscopy (EIS) were employed to study the composition, structure, and properties of the as-synthesised BiOCl/Bi 2 S 3 hybrids. Compared to pure Bi 2 S 3 and BiOCl products, the as-prepared BiOCl/Bi 2 S 3 hollow hybrids exhibited superior capability for photocatalytic reduction of hexavalent chromium under vis light irradiation. The photocurrent and EIS results demonstrated that the low recombination rate of photoinduced electron–hole pairs was contributed to the enhanced photoreduction activity.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2023
·
IF 10.9
Zhen Wan,Qihang Mao,Jingjing Xiang,Dongge Ma,Heqing Tang
A composite of SnS 2 and carbon nanotube (CNT) was successfully synthesized as a visible-light-driven photocatalyst with a mechanochemical method. In comparing with SnS 2 , the SnS 2 /CNT composite improved much the photocatalytic removal of Cr(VI) in acidic condition, which was confirmed to its special solid acid structure. During the synthesis of the SnS 2 /CNT composite by ball milling, S-C p-π bonding was formed between sulfur atoms in SnS 2 and carbon atoms in CNT. The generated S-C p-π bonding enhanced the transfer of photo-induced electrons in the bulk phase of the composite photocatalyst under visible light irradiation. Moreover, the persistent radical sites on CNT were able to trap photo-induced electrons and served as conjugated acid sites in the photocatalysis, which increased surface concentration of protons through their association with H + . These made the catalyst have a solid acid structure with plentiful surface protons, promoting the interfacial electron transfer between the catalysts and Cr(VI) and increasing the source of H + for the reduction of Cr(VI). As a result, the photocatalytic reduction rate of Cr(VI) on the SnS 2 /CNT composite were dramatically enhanced, being about 800% that on SnS 2 . On the basis of various characterizations and probe experiments, we confirmed the significance of the solid acid structure of the photocatalyst and clarified the catalytic mechanism of the new photocatalyst. Our finding may provide a new strategy to prepare highly active photocatalysts for proton-involved reactions.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Energies
·
2022
·Vol. 15
·期 22
·8717
·
IF 3.252
Quan Xu,Xinyi Chen,Siyang Wang,Chao Guo,Yingchun Niu,Runguo Zuo,Ziji Yang,Yang Zhou,Chunming Xu
Iron–chromium redox flow batteries (ICRFB) possess the advantage of low raw material cost, intrinsic safety, long charge–discharge cycle life, good life-cycle economy, and environmental friendliness, which has attracted attention from academia and industry over time. The proton exchange membrane (PEM) is an important part of the ICRFB system, impacting the efficiency and lifetime of the battery. Currently, the most widely used PEMs in the market are per-fluorinated sulfonic acid (PFSA) membranes, which possess high electrolyte stability and achieve the separation of positive and negative electrolytes. In addition, the complex preparation process and extremely high market price limited the usage of PEM in ICRFB. In this paper, we developed a remanufactured membrane (RM) strategy from waste PFSA resins. The RM has higher electrical conductivity and better proton transport ability than the commodity membrane N212. In the cell performance test, the RM exhibits similar coulombic efficiency (CE) as N212 at different current densities, which is stabilized at over 95%. Furthermore, the voltage efficiency (VE) and energy efficiency (EE) of the RM are improved compared to N212. At a current strength of 140 mA cm−2, the degree of energy loss is lower in the RM, and after 60 cycles, the capacity decay rate is lower by only 16.66%, leading to long-term battery life. It is a cost-effective method for membrane recovery and reformulation, which is suitable for large-scale application of ICRFB in the future.
研究领域:
材料科学
·
能源技术
·
环境工程
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2021
·
IF 5.165
Weiwei Cao,Xiaoyan Yang,Cécile Genevois,Mathieu Allix,Xiaojun Kuang
The new 8-layer twinned hexagonal solid solution Ba8Cr4–xTa4+0.6xO24 (x = 0.0–3.0) was isolated through the aliovalent substitution of Ta5+ for Cr3+ in Ba2CrTaO6, showing the widest B-site vacancy content range among the 8-layer twinned hexagonal perovskites. Ba8Cr4–xTa4+0.6xO24 forms a simple 8-layer hexagonal perovskite structure within 0.0 ≤ x < 2.4 and a tripled 8-layer hexagonal perovskite superstructure within 2.4 ≤ x ≤ 3.0. The latter shows expanded a and b axes by times in comparison to the simple 8-layer hexagonal perovskite structure owing to the partial face-sharing octahedral (FSO) B cation ordering along the ab plane. The B-cation and vacancy distributions in the tripled superstructure were characterized by neutron and X-ray powder diffraction and further confirmed by a scanning transmission electron microscopy–high angle annular dark field imaging and intensity profile analysis. The formation of 8-layer twinned hexagonal perovskites Ba8Cr4–xTa4+0.6xO24 in an extended solid solution range can be attributed to the presence of both covalent B–B and B–O–B bonding and B-site vacancies in the FSO sites. This work provides an effective way of combining covalent B–B and B–O–B bonding and vacancy creation as well as the cationic ordering in the FSO sites to reduce electrostatic repulsion, which could further enable the stabilization of new hexagonal perovskite compounds.
研究领域:
材料科学
·
晶体学
✓ 已验证
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2019
·
IF 3.206
Junling Duan,Li Zhao,Wei Lv,YiJing Li,Yuanhong Zhang,Shiyun Ai,Lusheng Zhu
The g-C 3 N 4 /Fe 3 O 4 nanocomposites with good fluorescence and magnetic property were designed and prepared for simultaneous detection and separation of trace Cr(VI) in water. The g-C 3 N 4 /Fe 3 O 4 nanocomposites based fluorescent sensor for Cr(VI) showed high sensitivity and selectivity. The linear response range of Cr(VI) was found to be 0 to 600 μM with a detection limit of 0.5 μM. In addition, the g-C 3 N 4 /Fe 3 O 4 as a novel adsorbent had effective removal towards Cr(VI). The adsorption capacity could reach 59.2 mg/ g. Furthermore, the g-C 3 N 4 /Fe 3 O 4 nanocomposites displayed superparamagnetic properties, allowing them to be easily separated from the liquid phase via an external magnetic field .
研究领域:
环境化学
·
分析化学
·
纳米材料学
·
环境污染与控制
·
水处理技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 16
·9836-9851
·
IF 4.22
Huang Xinping,Zhang Zhengyu,He Jielong,Bai Zhe,Lu Lu,Li Jun
Abstract Li-rich layered oxides are identified as the most promising cathode material for lithium ion batteries due to their high specific capacity and energy density. However, capacity fading, voltage decay and inferior rate capability have restricted its development in industry. Herein, we developed a novel cation/anion (chromium/fluorine) co-doping methods to enhance the electrochemical performance of Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 . X-ray diffraction, scanning electron microscopy, and transmission electron microscopy images reveal the perfect crystal structure. The Cr and F co-doped Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 shows the best discharge specific capacity, the highest rate performance and the lowest voltage decay. The initial discharge capacity is improved from 264.4 to 273.7 mAhg −1 . The capacity retention ratio is enhanced from 78.84% to 94.46% after 50 cycles. The R ct (charge transfer resistance) is decreased from 556.1Ω to 199.5Ω. The lower R ct and higher D Li+ of the Cr and F co-doped Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 contribute to the excellent rate capability. More importantly, the co-doped material exhibits elevated discharge voltage and shows lower discharge mean voltage decay (0.2945 V) than that of the pristine material (0.4396 V). These results fully suggest that cation and anion doping could effectively improve the electrochemical performances of Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 . Graphical Abstract
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Hualin Jiang,Menglin Li,Jun Liu,Xueqin Li,Lei Tian,Pinghua Chen
In this study, a novel CeO 2 -TiO 2 nanocomposite denoted as CeO 2 -3TiO 2 was successfully synthesized via a facile one pot hydro-thermal method without alkali. It exhibits high photocatalytic reduction reactivity toward Cr(VI) under visible light. The photocatalytic reactivity of CeO 2 -3TiO 2 is 18 times higher than that of pure CeO 2 , 28 times higher than pure TiO 2 , 15 times higher than the sample of simply mixed CeO 2 and TiO 2 . The solution with Cr(VI) initial concentration of 2780 ppb can be fast photoreduced by CeO 2 -3TiO 2 in 60 min under visible light to meet the criterion of U.S. Environmental protection Agency. Characterization results indicate CeO 2 -3TiO 2 has the good crystal form of heterojunction structure, narrow pore size distribution , narrow energy gap and high photogenerated electron-hole separation efficiency. Based on the experimental results, a speculated photocatalytic mechanism was proposed.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2021
·
IF 8.067
Mei Yu,Jing Shang,Yu Kuang
Graphene oxide (GO), a new and promising material, has been widely used as a co-catalyst in photocatalytic reactions; however, its capacity as a sole photocatalyst has rarely been investigated. In this study, ultraviolet (UV) light irradiation was used as a modification method to obtain reduced GO (rGO) samples. The samples were used as photocatalysts to examine their visible light photocatalytic activity toward hexavalent chromium (Cr(VI)) removal. Atomic force microscopy (AFM), X-ray diffraction (XRD), UV–vis spectrophotometry, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and electron spin resonance (ESR) spectroscopy were applied to interpret the surface and structure changes with UV irradiation. The oxygen-containing functional groups (OFGs) on the GO surface were reduced to defective carbons and π-conjugated C=C (sp 2 domains) under UV light; this led to a decrease in the interlayer distance between GO sheets, GO fragmentation, and increased disorder on the GO surface. The restoration of sp 2 domains led to a narrower band gap of GO, which favored the rGO excitation by visible light to generate electron-hole pairs. The rGO pre-irradiated with UV for 1h (rGO-1), possessing the highest defect density and electron generation efficiency, exhibited the best Cr(VI) reduction efficiency, which was about three times that of the GO sample; moreover, it outperformed most of the reported GO-based nanomaterials. In addition, low pH and the addition of citric acid as a hole scavenger could further improve the photocatalytic activity. This study proves that GO or rGO can be used as a sole photocatalyst under visible light to remove environmental pollutants such as heavy-metal ions, and it paves the way for the development of this kind of material and its UV-irradiation modification for further applications.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Dongsheng Xie,Shasha Chu,Shihua Zhang,Andrei Ivanets,Lijuan Zhang,Xintai Su
Electroplating sludge (ES) is a typical industrial hazardous waste , which contains multitudes of valuable transition metal resources. Hence, there is an urgent need for a method which can not only effectively detoxify, but also reasonably reuse ES resources. In this work, we synthesized Cr-doped ferrite catalyst (HT-ES) derived from Cr-containing ES v ia hydrothermal treatment, and applied it for the degradation of tetracycline (TCH). After hydrothermal treatment, the HT-ES with double metal oxide structure and large specific surface area (168.3 m 2 g −1 ) was obtained. The removal percentage of TCH could reach 90.79%, under the optimum conditions derived by response surface methodology . Experimental results demonstrated that HT-ES also exhibited high resistance to water impurities (i.e., Cl - , HCO 3 - , NO 3 and humic acid) and perfect reusability. The electron spin resonance and radical quenching experiments revealed that SO •- 4 , •OH and O •- 2 radicals appeared in the TCH degradation reaction system. Finally, a probable degradation mechanism of TCH was proposed based on the experimental results. This work not only achieved the stabilization of Cr-containing ES, but also obtained an excellent catalyst for the removal of TCH, realizing the goal of treating waste with waste.
研究领域:
环境科学
·
催化材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）