SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Xiaohui Zhan,Junyan Liu,Yue Zhao,Yanping Sun,Rui Gao,He Wang,Huixiang Shi
In this study, we designed and synthesized Mn III with tunable spin state in g-C 3 N 4 through one-step calcination of Mn-MOF. The Mn atoms were induced into the six-fold cavity of the g-C 3 N 4 lattice and formed Mn-N 6 coordination. Mn-MOF served as the source of Mn. The collapse of Mn-MOF effectively promoted the stripping of stacked layers in g-C 3 N 4 and increased the atomic loading. The Mn-N coordination induced impurity energy levels which effectively regulated Mnx-CN's bandgap structure and accelerated the migration and separation of carriers. The O 2 − was activated to 1 O 2 by the energy released from the high-spin Mn III transferred ground state. The H 2 production of Mn 10 -CN (13479.19 µmol·g −1 ·h −1 ) is ∼32.2 times that of CN under visible light irradiation and with a remarkable apparent quantum yield (AQY) of 12.23% at 420 nm. The rates of TC degradation and Cr (VI) reduction achieved 0.059 and 0.18 min −1 , respectively. In addition, the practical application conditions and catalytic mechanism of Mnx-CN were explored. This work demonstrates the connection of the spin state of metal with the photocatalytic activity, providing an efficient photocatalytic system that can be used for solar-chemical energy conversion and pollution remediation, and presenting a new approach for modifying the g-C 3 N 4 -based catalysts.
研究领域:
材料科学
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光催化
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环境科学
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能源转换
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产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2021
·Vol. 9
·期 15
·3401-3411
·
IF 6.331
Ming Wang,Miao Li,Yunli Wang,Yiran Shao,Yingchun Zhu,Shiping Yang
Hydroxyapatite (HA) has attracted wide attention for medical application due to its biocompatibility and bioactivity. However, the infection problems of HA remain among the leading reasons for implantation failure. Thus, it is urgent to endow HA biomaterials with antibacterial activity. Herein, the high antibacterial activity was achieved by introducing trace Mn3+ and H vacancy couples in HA through a facile heat-treatment strategy in air. The theoretical results indicated that Mn3+ was preferentially substituted for the Ca(2) site in the HA structure with a charge-compensating H vacancy appearing at the adjacent OH− site. The antibacterial tests showed that Mn-HA possessed antibacterial activity towards both E. coli and S. aureus with trace Mn content at the ppm level, and implied that Mn3+ and centers may play an important role in the antibacterial process. The Mn3+ and couples in Mn-HA, serving as oxidative and reductive centers respectively, could then collectively participate in the CoQ/CoQH2 redox cycling and synergistically facilitate the accumulation of CoQ˙− and ROS radicals. This enhanced ROS production was the main factor to endow Mn-HA with efficient antibacterial activity. Moreover, the in vitro bioactivity assay showed that Mn-HA materials exhibited enhanced osteogenic activity and good biocompatibility. Therefore, this work not only provides a feasible method to control the oxidation state of Mn elements in HA, but also proposes a novel trace Mn3+-doped HA for potential applications in tissue engineering.
研究领域:
材料科学
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生物材料
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生物医学工程
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2022
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IF 9.221
Kun Yu,Guangyao Zhang,Huining Chai,Lijun Qu,Dan Shan,Xueji Zhang
Metal−organic frameworks (MOFs) have emerged as promising materials for smart sensing and imaging applications. Here, a novel micron-biscuit Mn(III)-based porphyrinic MOF is synthesized with the modulation of 4,4′-biphenyldicarboxylic acid (BPDC). The anisotropic growth of MOF is induced by the increased steric hindrance , yielding micron-biscuit Mn-TCPP(BPDC) MOF crystals. Mn(III), as a sealer, quenched the intrinsic fluorescence of porphyrin because of the ligand-to-metal charge transfer (LMCT) effect, and this disappeared fluorescence can be regularly restored and enhanced due to LMCT effect inhibition and release of free porphyrin derived from the water-induced two-stage ligand exchange (TSLE) between BPDC, porphyrin and water. The as-prepared MOF acts as an excellent “signal-on” luminescent water-sensing probe with low amount (2.5 μg/mL) that can efficiently realize the trace detection of water in various organic media with high sensitivity, especially in dimethyl sulfoxide (DMSO), the detection limit is as low as 0.04% (v/v). Moreover, Mn-TCPP(BPDC) was successfully used for sensing water content in real commercial samples. This MOF with the guest-induced TSLE not only provides inspiration for the design of new luminescent materials, but also widens the path for smart sensing.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
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IF 6.551
Wenjing Zong,Zhaoming Guo,Minghuo Wu,Xianliang Yi,Hao Zhou,Siyuan Jing,Jingjing Zhan,Lifen Liu,Yang Liu
Endocrine-disrupting chemicals (EDCs) cause serious threats to human health. Five types of MnO 2 were synthesized and characterized. They exhibited different removal performances for three EDCs, i.e., estrone (E1), ethynylestradiol (EE2) and bisphenol A (BPA). Only δ-MnO 2 can completely remove E1 within 120 min at pH 3.0. Free Mn (III) was determined at the beginning of the reaction and participated in the EDCs removal process. Electron spin resonance (ESR) indicated that δ-MnO 2 could produce superoxide anions (·O 2 − ) and singlet oxygen ( 1 O 2 ) in the existence of methanol. The reactive oxygen species (ROS) quenching experiments showed 1 O 2 have certain contribution to the E1 removal by δ-MnO 2 . The source of ROS is mainly the lattice oxygen from δ-MnO 2 , and can be replenished through the layer structure destruction caused by the reaction between Mn(III) and E1. The ROS dependent EDCs removal by δ-MnO 2 leads to a deep understanding on this well-known oxidant.
研究领域:
环境科学
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化学工程
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水处理
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DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2015
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IF 5.33
Bo Sun,Xiaohong Guan,Jingyun Fang,Paul G. Tratnyek
MnO4– was activated by HSO3–, resulting in a process that oxidizes organic contaminants at extraordinarily high rates. The permanganate/bisulfite (PM/BS) process oxidized phenol, ciprofloxacin, and methyl blue at pHini 5.0 with rates (kobs ≈ 60–150 s–1) that were 5–6 orders of magnitude faster than those measured for permanganate alone, and ∼5 to 7 orders of magnitude faster than conventional advanced oxidation processes for water treatment. Oxidation of phenol was fastest at pH 4.0, but still effective at pH 7.0, and only slightly slower when performed in tap water. A smaller, but still considerable (∼3 orders of magnitude) increase in oxidation rates of methyl blue was observed with MnO2 activated by HSO3– (MO/BS). The above results, time-resolved spectroscopy of manganese species under various conditions, stoichiometric analysis of pH changes, and the effect of pyrophosphate on UV absorbance spectra suggest that the reactive intermediate(s) responsible for the extremely rapid oxidation of organic contaminants in the PM/BS process involve manganese(III) species with minimal stabilization by complexation. The PM/BS process may lead to a new category of advanced oxidation technologies based on contaminant oxidation by reactive manganese(III) species, rather than hydroxyl and sulfate radicals.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
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2023
·
IF 12.8
Zhicheng Liao,Huan He,Danni Cui,Jingye Cui,Xiaoxia Yang,Ziwei Guo,Hao Chen,Guohua Dao,Bin Huang,Hongwen Sun,Xuejun Pan
Algal extracellular organic matter (EOM), a major fraction of the dissolved organic matter found in eutrophic plateau lakes, can act as a photosensitizer to drive the abiotic oxidation of Mn(II). This process has the potential to generate reactive Mn(III) and influence the fate of organic pollutants. In this study, the photodegradation of 17α-ethinylestradiol (EE2) in the presence of Mn(II) and EOM was investigated with emphasis on the photogeneration mechanism of Mn(III). The results indicated that Mn(II) can accelerate EE2 photodegradation in EOM solution owing to the photogeneration of reactive Mn(III), and the enhancement was greater at higher Mn(II) concentrations. The generation of reactive Mn(III) was mainly attributable to the action of superoxide radical generated by photosensitization of EOM. In addition, the photodegradation of EE2 was slower at higher pH, possibly because of the deactivation of Mn(III) under alkaline conditions. Single-electron transfer was an indispensable process in the photodegradation. The differences in fluorophore content, pH, and NO 3 − concentrations are all important determinants for EE2 photodegradation in natural waters. The information obtained in this research would contribute to the understanding of reactions between Mn(II) and EOM, and provide new insights into the behaviors of reactive Mn(III) in eutrophic water irradiated by sunlight.
研究领域:
环境科学
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水污染治理
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产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Yiqing Liu,Ting Wang,Zhengjie Chen,Shenglan Liu,Yongsheng Fu
Currently, the research on bisulfite (BS) activation by Mn(II) is very limited probably because of the low catalytic efficiency of Mn(II). Adding ligands to Mn(II)/BS system is likely to improve the BS activation, but the relative information is very rare. Therefore, the effect of nitrilotriacetic acid (NTA) on Mn(II)/BS system was investigated in this work using sulfamethoxazole (SMX) as the target contaminant. The results showed that the addition of NTA enhanced SMX removal in Mn(Ⅱ)/BS system through forming Mn(Ⅱ/III)-NTA complexes driving Mn(III)/Mn(II) cycle and stabilizing Mn(III). Alcohol scavenging experiments and competitive kinetic experiments indicated that sulfate radical (SO 4 •− ) and hydroxyl radical (HO • ) were not the main reactive species in Mn(II)/NTA/BS system. Mn(Ⅲ) was the primary oxidant for SMX elimination in this system and its existence was proved by UV-Vis absorption spectrum of reaction solution. Mn(Ⅱ)/NTA/BS system could greatly degrade SMX in near-neutral conditions, while nearly no SMX removal was observed at pH 3.0. The decrease of dissolved oxygen concentration significantly inhibited BS autocatalytic stage, thus suppressing the removal of SMX. Due to the competitive complexation of HCO 3 − and FA with NTA for Mn(II), their addition in Mn(Ⅱ)/NTA/BS system obviously inhibited SMX degradation . Four intermediates were detected during SMX degradation in Mn(Ⅱ)/NTA/BS system, and the possible SMX transformation pathways were speculated as N-S bond breaking, hydroxylation, amino oxidation and coupling reaction.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2018
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IF 4.427
Xinghao Wang,Jiayi Yao,Siyuan Wang,Xiaoxue Pan,Ruiyang Xiao,Qingguo Huang,Zunyao Wang,Ruijuan Qu
Photodegradation of pollutants is classically explained by reaction with reactive oxygen species. However Mn(III) may also remove pollutants, but direct evidence is actually lacking. Here we investigated the role of soluble Mn(III) on phototransformation of four typical estrogens, namely estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-ethynylestradiol (EE2), in the presence of Mn(II) and humic acid . Conversion rates of 60.2%, 89.0%, 87.6%, and 80.2% were achieved for E1, E2, E3, and EE2, respectively, after 72 h visible light irradiation. A detailed quenching experiments revealed that soluble Mn(III), and not reactive oxygen species, was the oxidant responsible for estrogen removal. The determination of Mn(III) concentration provided direct proof of the role of Mn(III)-based oxidizers in the conversion of estrogens. Soluble Mn(III) can form complexes with humic acid, and about 6.51 μM of Mn(III)-humic acid was formed from 20 μM of Mn(II) in the presence of 5 mg/L of humic acid. Furthermore, product identification and theoretical computation demonstrated that estrogens are mainly converted into oligomers (dimers, trimers, tetramers, etc.) via a single-electron process. According to these results, the oxidation of Mn(II) to Mn(III) is initiated by superoxide ion (O 2 •- ) generated from dissolved oxygen in the presence of humic acid under visible light irradiation. The formed soluble Mn(III) strips the estrogens of a single electron to generate phenoxyl radicals, which undergo oligomerization, while leads to regeneration of Mn(II). Hence, the photochemical Mn(II)-Mn(III) redox cycling may significantly influence the fate and transformation of estrogens in waters.
研究领域:
环境科学
·
生物学
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2021
·
IF 9.297
Chuankun Yin,Siji Zhou,Keyi Zhang,Jiale Bai,Yangyang Lv,Xuewen Zhang,Xiaoxia Li,Aihua Xu
p-Nitrophenol (PNP) is one of the highly toxic and mutagenic pollutants existed in aquatic environment. In this work, the crednerite CuMnO 2 nanoflake was prepared and used to degrade PNP with peroxymonosulfate (PMS) as the oxidant. It was found that CuMnO 2 exhibited much higher activity than other Cu-based catalysts such as CuO, Cu 2 O, CuFe 2 O 4 and CuFeO 2 , with 90% of PNP degraded after 10 min under mild reaction conditions. The catalyst was also stable during five successive runs. Sulfate and hydroxyl radicals produced from PMS reduction by Cu(I) species, as well as superoxide ions and single oxygen, contribute to the degradation of PNP. More importantly, the interactions between Mn and Cu species in CuMnO 2 were identified by X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FT-IR) and linear sweep voltammetry (LSV), and were further confirmed by the control experiment with the mixture of Cu 2 O + Mn 2 O 3 . The results implied that the high valent Mn(III) species acted as Lewis acids to withdraw electron from PMS, resulting that the Cu(I) species can be easier oxidized to Cu(II) by PMS with the formation of radicals. These findings provide an ideal bimetallic heterogeneous catalyst and a new mechanism for PMS-mediated reaction.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2026
·
IF 5.1
Shangyi Zhao,Jing Li,Yanchanjuan Yang,Shuaiqi Zhao,Aihua Xu,Xiuying Liu,Xiaoxia Li
Sulfite (SO 3 2− ) has emerged as an economical and eco-friendly precursor for reactive species generation in advanced oxidation processes (AOPs). However, conventional activation strategies typically require high sulfite inputs and generate non-selective radicals, limiting their efficiency and practicality. Here, we demonstrate that a trace amount of water‑soluble manganese porphyrin complex (Mn(III)‑TCPP, as low as 4 μM), can efficiently activate Na 2 SO 3 at ultralow concentrations (10–100 μM) to degrade sulfadiazine. The Mn(III)-TCPP/Na 2 SO 3 system exhibited an initial rate 41 times faster than the Mn 2+ /Na 2 SO 3 system and 4.2 times greater than the reported -Mn(III)-NTA/Na 2 SO 3 system. A linear correlation between the degradation rate constant and the Hammett constant (σ + ) of porphyrin substituents confirms that ligand electronic structure modulates Mn redox cycling during SO 3 2− oxidation by dissolved O 2 . Mechanistic studies, including time‑resolved spectroscopy, electrochemical analysis, and reactive species trapping, reveal that the reaction proceeds primarily via superoxide radical and singlet oxygen, representing a distinct departure from conventional sulfate radical or high-valent Mn(V) that has been reported in other metal–ligand AOP systems. This work establishes a new, highly efficient sulfite activation driven by an ultralow-dose metalloporphyrin catalyst and provides fundamental insight into non‑radical oxidation routes for sulfite-based AOPs.
✓ 已验证
DOI
高影响因子
Journal of Water Process Engineering
·
2023
·
IF 7
Jinbing Huang,Xiaoyan Liu,Shiwei Xie
Although electrochemical activation of permanganate ( E -PM) is a green and efficient method to degrade refractory organics by in-situ generated reactive Mn( III ) aq , this process highlights on the presence of promoter and/or stabilizer. Oxalate (OA) is a widespread organic chelate in natural water bodies (with concentrations up to 1 mM), but whose effect on the E -PM process is still unclear. In this study, we found electrolysis and the presence of OA both promote the activation of PM for the degradation of diclofenac (DCF), showing a high synergistic coefficient (3.23) and elevated reaction constant (0.1395 min −1 ). Nevertheless, this process is highly pH-dependent, behaving decreased reactivity as pH value increasing from 3 to 11. Sufficient concentration of OA (≥0.5 mM in this study) is required for stabilizing Mn(III). UV–vis spectra, visual evidence and quenching experiments identified the presence and dominant role of Mn(III)-OA on the degradation of DCF. Using chronoamperometry, we confirmed Mn(III)-OA was primarily generated from the electro-reduction of PM in the presence of OA at pH 5.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2020
·Vol. 8
·期 7
·1507-1515
·
IF 5.344
Kai Xu,Zhenghuan Zhao,Junfeng Zhang,Wei Xue,Haipeng Tong,Heng Liu,Weiguo Zhang
Mn(IV)-Based nanoparticles (NPs) are effective in improving tumor oxygenation (hypoxia) and reducing endogenous hydrogen peroxide and acidity in the tumor region. However, the optimized reduction conditions of conventional Mn(IV)-based NPs are generally reported at pH ≤ 6.5, while the usual pH range of the tumor microenvironment (TME) is 6.5–7.0. The dissatisfactory imaging performance in the weakly acidic environment may limit their further application in tumor diagnosis. In this study, Mn(III) was introduced in a nanoplatform, because it is reduced into Mn(II) in weakly acidic environments. Arg-Gly-Asp (RGD) peptide-decorated bovine serum albumin (BSA) was employed as the stabilizer and scaffold to fabricate Mn(III)- and Mn(IV)-integrated nanocomposites (RGD-BMnNPs) with suitable size, good stability, and excellent biocompatibility. The as-prepared NPs showed clear contrast enhancement at pH 6.5–6.9 in vitro as well as sensitive and rapid T1-weighted imaging performance within the tumor region in a glioblastoma (U87MG) orthotopic model, owing to the intrinsic disproportionation reaction of Mn(III) in the weakly acidic environment. In addition, these NPs could be used for efficient siRNA delivery. They showed superior advantages in this process, including increased tumour uptake, improved tumor accumulation and enhanced therapeutic effects with the modulation of the TME. These novel albumin-stabilized manganese-based NPs combined with efficient drug delivery capacity hold great potential to serve as intelligent theranostic agents for further clinical translation.
研究领域:
生物医学工程
·
纳米技术
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癌症研究
·
神经科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）