RSC Advances
·
2017
·Vol. 7
·期 84
·53076-53086
·
IF 3.108
Xin Jin,Weiquan Cai,Zhijun Cai
Ordered mesoporous alumina (MA) was successfully modified with three amino organosilanes including 3-aminopropyltriethoxysilane (1N), N-(β-aminoethyl)-γ-aminopropylmethylbimethoxysilane (2N) and N-3-trimethoxysilylpropyldiethylenetriamine (3N) via a facile grafting method, and the as-prepared amino organosilane grafted MA–1N, MA–2N and MA–3N show enhanced adsorption performance towards Cr(VI) removal from wastewater. Their physicochemical properties and the MA before modification were comparatively characterized by FT-IR, TEM, XRD, N2 adsorption–desorption, CHNS elemental analysis, zeta potential measurements and XPS. Their adsorption performance was also comparatively studied along with the effect of contact time, adsorption isotherms, multi-metal ion adsorption, interference of co-existing anions and regeneration ability in batch experiments. It was found that their adsorption kinetics data were better fitted by the pseudo-second order model; adsorption isotherms were better described by the Langmuir isotherm for MA–1N, the Freundlich isotherm for MA–2N and the Temkin isotherm for MA–3N. Among them, MA–2N shows the maximum adsorption capacity of 137.9 mg g−1 which is more than twice the 59.4 mg g−1 of MA. The residual concentration of Cr(VI) with a concentration of 50 mg L−1 when treated with MA–2N meets the emission standard of the World Health Organization (WHO). Moreover, MA–2N shows better selectivity toward Cr(VI), and can reduce relatively more Cr(VI) to low toxicity Cr(III). More results were found that Cr(VI) is adsorbed on the surface through a monodentate ligand or bidentate ligand, and then Cr(VI) is reduced to Cr(III) by an adjacent electron donor, after which Cr(III) is co-precipitated with the adsorbents. All the amine-grafted samples show good reusability for 5 cycles. These results indicated that the amino organosilane grafted ordered MA with high adsorption capacity, good selectivity and favourable reusability is a promising candidate for Cr(VI) removal, in combination with its low cost and energy saving preparation process.
✓ 已验证
DOI
高影响因子
MOLECULES
·
2021
·Vol. 26
·期 22
·7054
·
IF 4.412
Juan Liang,Chengjun Jing,Jiarong Wang,Yupawang Men
Graphitic carbon nitride (g-C3N4) photocatalysts were synthesized via a one-step pyrolysis process using melamine, dicyandiamide, thiourea, and urea as precursors. The obtained g-C3N4materials exhibited a significantly different performance for the photocatalytic reduction of Cr(VI) under white light irradiation, which is attributed to the altered structure and occupancies surface groups. The urea-derived g-C3N4with nanosheet morphology, large specific surface area, and high occupancies of surface amine groups exhibited superior photocatalytic activity. The nanosheet morphology and large surface area facilitated the separation and transmission of charge, while the high occupancies of surface amine groups promoted the formation of hydrogen adsorption atomic centers which were beneficial to Cr(VI) reduction. Moreover, the possible reduction pathway of Cr(VI) to Cr(III) over the urea-derived g-C3N4was proposed and the reduction process was mainly initiated by a direct reduction of photogenerated electrons.Keywords:Cr (VI) reduction;photocatalytic;g-C3N4precursors;nanosheet morphology;surface characteristics
✓ 已验证
DOI
PubMed
高影响因子
CRYSTAL GROWTH & DESIGN
·
2025
·
IF 3.4
Lizhen Zhang,Lehui Liu,Feifei Yuan,Yisheng Huang,Zhoubin Lin
Enhancing the luminous intensity of near-infrared (NIR) phosphors is critical for practical applications. This study demonstrates that codoping charge-compensating ions (Li+, Na+, and K+) significantly improves the fluorescence emission intensity and quantum efficiency of Cr3+-doped CaMgSi2O6 (CMSO:Cr) phosphors. Optimal enhancements were achieved with specific ion concentrations: the CMSO:0.01Cr phosphor codoped with 0.8 at. % Na2CO3 exhibited a 1.8-fold increase in emission intensity, while the CMSO:0.04Cr phosphor codoped with 1.5 at. % Li2CO3 demonstrated an 8-fold enhancement. Charge compensation also improved the internal quantum yield (IQY) and photoelectric conversion efficiency without compromising the thermal stability. Mechanistic insights from absorption/emission spectra, electron paramagnetic resonance (EPR), and fluorescence lifetime analyses revealed that alkali metal ions occupy defect sites, suppress nonradiative recombination, and simplify emission profiles by eliminating defect-induced luminescent centers.
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Iranian Chemical Society
·
2020
·Vol. 18
·期 1
·159-166
·
IF 1.552
Xu Wenjing,Ye Liuqing,Li Wei,Zhang Zhanying
MIL-101(Cr) morphology was modulated by addition of sodium stearate (SS) and cetyltrimethylammonium bromide (CTAB) in the precursor solution. The resulting SS modulation MIL-101(Cr) (SS@MIL-0.1 and SS@MIL-0.2) are quasi-spherical, and the CTAB modulation MIL-101(Cr) (CTAB@MIL-0.2) has a regular octahedral shape, similar to the pure MIL-101(Cr). Their particles after modification are reduced, and the structures of MIL-101(Cr) crystals are not destroyed. These modifications improve their adsorption capacity for methyl orange (MO). The maximum adsorption capacity of MO on the CTAB@MIL-0.2 and SS@MIL-0.2 can reach 645.2 and 454.5 mg g −1 , respectively, superior to many adsorbents reported in the literatures. The CTAB@MIL-0.2 and SS@MIL-0.2 exhibit outstanding selective adsorption of MO from the mixed solution of MO and methylene blue (MB). Our work may provide a feasible method to obtain MIL-101(Cr) with different morphologies, especially quasi-spherical, and open up a new doorway for utilizing MIL-101(Cr).
✓ 已验证
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2014
·
IF 3.633
Wei Yao,Tao Ni,Shujun Chen,Hao Li,Yun Lu
Novel hybrid nanocomposites constructed via anchoring the Fe 3 O 4 @polypyrrole nanospheres with hierarchical porous structure on graphene nanosheets (graphene/Fe 3 O 4 @polypyrrole, GFP) have been prepared, and characterized by using TEM, XRD , XPS, FT-IR and TGA . The large saturation magnetization of 12.4 emu g −1 allows fast and economic separation of the GFP from solution. Due to the synergic effect between graphene and Fe 3 O 4 @polypyrrole, the GFP exhibits excellent adsorption capability of 348.4 mg g −1 for Cr(VI) removal, which is much higher than the previously reported values of other magnetic nanomaterials . Furthermore, the GFP is stable and recyclable, retaining about 72.2% of the removal efficiency after six adsorption–desorption cycles. The adsorption isotherms and kinetics could be well simulated by the Langmuir and pseudo-second-order models respectively. The GFP nanocomposites could be a good candidate for efficient Cr(VI) removal from the wastewater.
✓ 已验证
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Zhichang Ma,Jing Sun,Hemeiling Cai,Junwei Di
A photoelectrochemical (PEC) sensor based on a BiVO 4 semiconductor and gold nanoparticles (AuNPs) was successfully prepared for the sensitive detection of Cr(Ⅵ) ions. The calcination temperature was found to be very important for the PEC properties of BiVO 4 . The BiVO 4 -modified indium tin oxide electrode (ITO/BiVO 4 ) calcined at 300 °C generated a low cathodic photocurrent response under light irradiation. BiVO 4 /AuNPs materials were coupled via electrostatic adsorption to enhance the photoelectric conversion performance of BiVO 4 . The use of self-assembled monolayers (SAMs) to modify electrodes reduce the background current. The developed ITO/BiVO 4 /AuNPs/L-Cys PEC sensor was used to detect of Cr(VI). The Cr(Ⅵ) ion concentrations showed a good linearity between 10 pM and 1 μM with a detection limit of 9.1 pM (S/N = 3). The prepared PEC sensor exhibited high sensitivity, a wide linear range, and good selectivity. This work provides a promising platform for the analytical detection of heavy metal ions.
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2024
·Vol. 14
·期 5
·289
·
IF 3.8
Sai An,Ying Wang,Huajian Qiao,Hao Xiu,Deyu Liu,Yongbo Kuang
Photoelectrocatalytic approaches show promise for contaminate removal in wastewater through redox reactions. However, the direct treatment of very low concentration heavy metals is a challenging task. Copper bismuth oxide is considered as a potential photocathode material due to its appropriate bandgap width and excellent light absorption properties. In this work, we utilize copper bismuth oxide photoelectrodes with micrometer-scale pores to achieve the efficient and complete reduction of micromolar-level hexavalent chromium(VI) in wastewater. In a continuous 180 min experiment, the reduction rate of 5 µM hexavalent chromium reached 97%, which is an order lower than the drinking standard. Such a process was facilitated by the unique hierarchical microstructure of the oxide thin film and the porous morphology. On the other hand, the structural evolution during the operation was analyzed. A surface passivation was observed, suggesting the possible long-term practical application of this material. This study serves as an important reference for the application of photoelectrocatalysis in addressing Cr(VI) pollution in wastewater, with implications for improving water quality and environmental protection.
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2025
·
IF 5.1
Yunzi Wang,Junyu Chen,Chongyu Li,Quanqi Yang,Jianjun Wang
Metal-organic frameworks (MOFs), as promising photocatalysts, have been widely used in Cr(VI) removal due to their high porosity and structural tunability, whereas the simple hybridization of MOFs was not beneficial for the separation of photogenerated carriers. In this study, a novel Al-doped and hydroxyl-functionalized Zr-based MOF (named as Al/Zr-UiO-66-(OH)2) was synthesized via dual strategies of bimetallization and hydroxylation. Characterization results confirmed that the incorporation of Al and hydroxyl groups effectively reduced the bandgap and enhanced separation efficiency of photogenerated charge. Al/Zr-UiO-66-(OH)2 (1:5) exhibited outstanding photocatalytic reduction performance towards Cr(VI) (99.3% within 2 h) under visible light. The photocatalytic rate of Al/Zr-UiO-66-(OH)2 (K = 0.0148 min-1) was 74 times higher than that of UiO-66 (K = 0.0002 min-1). Trapping experiments, EPR and XPS analysis revealed that highly efficient photoreduction of Cr(VI) into Cr(III) was attributed to electrons and ·O2- radicals. These findings provide a feasible strategy for designing MOF-based photocatalysts for practical environmental remediation.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Chao Zhang,Mingxia Yan,Wenting Li,Ce Han,Jie Li,He Zhao,Guixiao Jia,Shengli An,Xinping Qiu
Due to the high theoretical specific capacity and low cost, FeF3·0.33H2O has become one of the potential choices of cathode materials for sodium-ion batteries. However, the poor intrinsic conductivity limits its practical applications. Herein, the atomic substitution is used to improve its intrinsic conductivity. The first-principles calculation results show that Cr3+ doping can reduce the band gap of FeF3·0.33H2O to improve its intrinsic conductivity. The discharge specific capacity of Fe0.95Cr0.05F3·0.33H2O with a narrowest band gap is 194.02 mA h/g at 0.1 C within the range of 1.4–4.0 V, which is higher than that of FeF3·0.33H2O (136.47 mA h/g). Using the electrochemical impedance spectroscopy and galvanostatic intermittent titration technique tests, it is found that Rct of Fe0.95Cr0.05F3·0.33H2O is reduced and DNa+ is almost unchanged, as compared to FeF3·0.33H2O.
✓ 已验证
DOI
高影响因子
TALANTA
·
2026
·
IF 6.7
Kaiyuan Zhang,Lian Xia,Jiazhen Shi,Han Tao,Jianli Zhou,Yuangen Wu
A new Ag/Cu metal-organic nanozyme with MOF-like features was developed. • Dual ligands and Ag/Cu co-incorporation enable dual enzyme-mimicking activities. • “Kill two birds with one stone”: one nanozyme discriminates Cr(III) and Cr(VI). • Orthogonal channels allow direct Cr(III)/Cr(VI) quantification without subtraction. • Smartphone-assisted analysis enables chromium speciation in river water. Chromium predominantly exists as Cr(III) and Cr(VI) in aquatic environments, which differ markedly in physicochemical properties and toxicity. Rapid and direct discrimination of Cr(III) and Cr(VI) remains challenging because conventional chromium speciation methods often require redox pretreatment, multiple recognition elements, or indirect calculation. Herein, a new Ag/Cu-containing metal-organic nanozyme with MOF-like structural characteristics (Ag-BC@Cu) was developed. Ag-BC@Cu exhibited laccase-like and peroxidase-like activities and was used to construct an orthogonal colorimetric sensor for discrimination of Cr(III) and Cr(VI). Cr(III) selectively inhibited the laccase-like pathway, whereas Cr(VI) enhanced the peroxidase-like pathway, producing independent colorimetric responses at 510 and 652 nm, respectively. Generally, both chromium species were directly discriminated and quantified using a single nanozyme without redox pretreatment, multiple probes, or subtraction-based calculations. The detection limits of the orthogonal colorimetric sensor were 0.05 mg·L -1 for Cr(III) and 0.0047 mg·L -1 for Cr(VI). Smartphone-assisted analysis further enabled portable visual detection of chromium speciation. The colorimetric sensor exhibited good selectivity and was successfully applied to river-water samples, with results consistent with LC-ICP-MS. This work provides a simple “kill two birds with one stone” strategy for chromium speciation, with potential for portable water-quality monitoring. A dual enzyme-mimicking Ag-BC@Cu nanozyme enabled the orthogonal colorimetric detection of Cr(III) and Cr(VI). Cr(III) selectively inhibited the laccase-like activity, whereas Cr(VI) enhanced the peroxidase-like activity, enabling successful application to river-water samples. Download: Download high-res image (297KB) Download: Download full-size image
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2026
·
IF 3.4
Jing-Jing Li,Can-Jun Zou,Wei Tang,Cheng-Yu Zhang,Jian-Hua Jia,Ping-Ping Fang
The detection of purine drugs has been a persistent concern among scientists in the biology and medicine fields over the past few decades. However, achieving both high sensitivity and selectivity in the detection of purine drugs sharing similar molecular structures remains a significant challenge. Herein, we achieve both high detection sensitivity and selectivity for purine drugs with similar structure on the Gold/Materials of Institut Lavoisier-101(Au/MIL-101) composite by surface-enhanced Raman scattering (SERS). In water solution, the detection sensitivity for adenine (Ade) is as low as 1 ng·mL–1. Importantly, in serum containing Ade, 6-mercaptopurine, and allopurinol, Ade can be selectively detected with a detection limit of 3 ng·mL–1, indicating excellent anti-interference capability and practical application potential. Such high detection sensitivity is attributed to the specific adsorption between the amino group of the Ade and the carboxyl groups of the Materials Institut Lavoisier-101(Cr) (MIL-101(Cr)). This work provides a strategy for detecting structurally similar drugs and illustrates the potential use of functionalized SERS substrates in pharmaceutical analysis and therapeutic drug monitoring.
✓ 已验证
DOI
高影响因子
PLANT AND SOIL
·
2026
·
IF 4.8
Cai Qiyang,Xu Fanghao,Zhang Shuaishuai,Cao Fengjing,Wang Ke,Dong Daming,Zhao Xiande
Aims Plants serve as bioindicators of environmental heavy metal pollution. Rapid, non-destructive techniques for plant elemental analysis are essential for understanding pollutant uptake and nutrient interactions. This study aimed to develop a novel approach integrating Laser-Induced Breakdown Spectroscopy (LIBS) with guttation fluid for non-destructive monitoring of elemental dynamics in Alocasia under Cr (III) stress. Methods Guttation fluid (easy to collect and with a large volume) was collected non-destructively from hydroponically cultivated Alocasia plants subjected to Cr (III) stress. LIBS analysis was performed on fluid samples using a liquid-to-solid enrichment strategy to enhance trace detection. Signal validation was conducted via comparison with Inductively Coupled Plasma Mass Spectrometry (ICP-MS) measurements. Results Guttation fluid elemental composition strongly correlated with plant tissues. Under Cr(III) stress, Cr signal intensity increased with stress concentration, while Mg and Ca signals decreased by approximately 30–40%. The accumulation of Cr in guttation fluid continued to rise to a peak and then decreased (likely associated with root damage). LIBS results showed significant correlation with those obtained by ICP-MS (R 2 = 0.995 for Cr(Ⅰ)). The method achieved a detection limit of 20.3 ppb for Cr with excellent linearity (R 2 = 0.963). Conclusion This LIBS-guttation fluid approach provides a reliable, non-destructive means to monitor plant responses to heavy metal stress, offering potential for environmental biomonitoring and crop safety assessment.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）