ANALYST
·
2012
·Vol. 137
·期 19
·4552-4558
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IF 4.23
Xing Liu,Qi Wang,Huihui Zhao,Lichun Zhang,Yingying Su,Yi Lv
Inorganic nanomaterials that mimic enzymes are fascinating as they potentially have improved properties relative to native enzymes, such as greater resistance to extremes of pH and temperature and lower sensitivity to proteases. Although many artificial enzymes have been investigated, searching for highly-efficient and stable catalysts is still of great interest. In this paper, we first demonstrated that bovine serum albumin (BSA)-stabilized MnO2 nanoparticles (NPs) exhibited highly peroxidase-, oxidase-, and catalase-like activities. The activities of the BSA-MnO2 NPs were evaluated using the typical horseradish peroxidase (HRP) substrates o-phenylenediamine (OPD) and 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of either hydrogen peroxide or dissolved oxygen. These small-sized BSA-MnO2 NPs with good dispersion, solubility and biocompatibility exhibited typical Michaelis–Menten kinetics and high affinity for H2O2, OPD and TMB, indicating that BSA-MnO2 NPs can be used as satisfactory enzyme mimics. Based on these findings, BSA-MnO2 NPs were used as colorimetric immunoassay tags for the detection of goat anti-human IgG in place of HRP. The colorimetric immunoassay using BSA-MnO2 NPs has the advantages of being fast, robust, inexpensive, easily prepared and with no HRP and H2O2 being needed. These water-soluble BSA-MnO2 NPs may have promising potential applications in biotechnology, bioassays, and biomedicine.
研究领域:
材料科学
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生物化学
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生物技术
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2017
·
IF 6.395
Qiang Lu,Li Liu,Shuanglei Yang,Jun Liu,Qingyong Tian,Weijing Yao,Qingwen Xue,Mengxiao Li,Wei Wu
More convenience and intelligence life lead by flexible/wearable electronics requires innovation and hommization of power sources. Here, amorphous FeOOH/MnO 2 composite as screen-printed electrode materials for supercapacitors (SCs) is synthesized by a facile method, and solid-state flexible SCs with aesthetic design are fabricated by fully screen-printed process on different substrates, including PET , paper and textile. The amorphous FeOOH/MnO 2 composite shows a high specific capacitance and a good rate capability (350.2 F g −1 at a current density of 0.5 A g −1 and 159.5 F g −1 at 20 A g −1 ). It also possesses 95.6% capacitance retention even after 10 000 cycles. Moreover, the all-printed solid-state flexible SC device exhibits a high area specific capacitance of 5.7 mF cm −2 and 80% capacitance retention even after 2000 cycles. It also shows high mechanical flexibility. Simultaneously, these printed SCs on different substrates in series are capable to light up a 1.9 V yellow light emitting diode (LED), even after bending and stretching.
研究领域:
材料科学
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能源存储与转换
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Jingmin Yan,Zhengchen Li,Licheng Ma,Peiwei Han,Wenkai Zhao,Shufeng Ye
In this study, a highly efficient CuO/α-MnO 2 bimetallic catalyst was synthesized by hydrothermal and calcination methods and employed as a peroxydisulfate (PDS) activator for the degradation of thiocyanate (SCN − ) in aqueous phase. The effect of calcination temperature on the catalytic performance of CuO/α-MnO 2 and the mechanism of the CM350/PDS system were studied. Under optimal conditions, almost 100 % of SCN − (100 mg/L) was degraded within 90 min. XRD , XPS , Raman, and H 2 -TPR analyses revealed that the catalytic performance was enhanced in the CM350 catalyst due to the formation of M-O-Cu + -like structures (M = Mn 3+ , Mn 4+ , Cu 2+ ) through the combination of α-MnO 2 with CuO . The structures exhibit excellent redox ability and facilitate electron transfer between Cu and Mn elements, thereby improving the activation effect of PDS. Besides, the Cu 1.5 Mn 1.5 O 4 generated from the high calcination temperature was not conducive to the SCN − degradation reaction. Moreover, the mechanism study indicated that SO 4 ·- , ·OH, and the electron transfer pathway mainly accounted for the SCN − degradation. This study provides some guidance for the synthesis of PDS activation materials and the treatment of industrial wastewater by an advanced oxidation process .
研究领域:
环境科学
·
化学工程
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产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2022
·Vol. 10
·期 22
·4274-4284
·
IF 7.571
Changchun Wen,Xiaolu Guo,Cunji Gao,Zhongkai Zhu,Nianqi Meng,Xing-Can Shen,Hong Liang
Specific tumor-responsive capabilities and efficient synergistic therapeutic performance are the keys to effective tumor treatment. Herein, AuNRs@SiO2–RB@MnO2 was developed as a new type of tumor-responsive nanotheranostic for multimodal imaging and synergistic chemodynamic/photothermal therapy. In AuNRs@SiO2–RB@MnO2, the SiO2 layer wraps the AuNRs, providing light absorption in the second near-infrared (NIR-II) region. The SiO2 layer also adsorbs the MnO2 nanosheets, which have Fenton-like activity, resulting in a fluorescent sensing platform based on the fluorescence quenching properties of MnO2 for rhodamine B dye. The fluorescence can be recovered by the consumption of MnO2 by glutathione, which simultaneously produces Mn2+ in the tumor region. The recovery of fluorescence reflects the consumption of glutathione and the increase in Mn2+, which produces hydroxyl radicals via Fenton-like reaction in the tumor microenvironment to realize chemodynamic therapy. Meanwhile, the AuNRs are a good photothermal reagent that can effectively absorb NIR-II light and convert it into heat energy to kill tumor cells via photothermal therapy. The NIR-II absorption performance of the AuNRs provides good photoacoustic imaging and deep photothermal performance, which is favorable for efficient NIR-II photoacoustic imaging-guided photothermal therapy. As a result, the AuNRs@SiO2–RB@MnO2 nanotheranostic exhibits outstanding imaging and synergistic chemodynamic/photothermal therapeutic performance for tumor imaging and treatment.
研究领域:
生物医学工程
·
纳米医学
·
肿瘤学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2016
·
IF 4.836
Xiuqin Tan,Yifeng Wan,Yajing Huang,Chun He,Zaili Zhang,Zhuoyan He,Lingling Hu,Jiawei Zeng,Dong Shu
Three-dimensional (3D) MnO 2 porous hollow microspheres (δ- and α- MnO 2 PHMSs), with high adsorption and catalytic ozonation performance, were synthesized by a self-template (MnCO 3 microspheres) process at room temperature. The synthesized MnO 2 PHMSs were characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area. The results showed that PHMSs exhibit the excellent adsorption ability and catalytic activity owning to their hollow spherical structure, mesoporous shell and well-defined interior voids, leading to the strong adsorption for bisphenol A (BPA) and the retention of O 3 molecules on catalyst. Moreover, the catalytic performance of α-MnO 2 PHMSs was better than that of δ-MnO 2 PHMSs which was attributed to the richer lattice oxygen of α-MnO 2 PHMSs to accelerate O 3 decomposition by producing more reactive oxidative species. The degradation efficiency of BPA using 3D α-MnO 2 PHMSs was more than 90% in the presence of ozone within 30 min reaction time. The probe tests for reactive oxidative species (ROSs) displayed that BPA degradation by catalytic ozonation is dominated by O 2 − and OH in our present study. Furthermore, the organic compounds as intermediates of the degradation process were identified by LC/MS.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Minzhi Du,Kun Zhang
Transition-metal-oxide-based electrochemical electrodes usually suffer from poor electron and ion transport, leading to deteriorated rate performance and cycling stability. Herein, we address these issues by developing a facile “conducting encapsulation” strategy toward a nanoporous PEDOT nanowire/MnO2 nanoparticle/PEDOT nanowire composite electrode. Through encapsulation of the PEDOT nanowire network, the overall electrochemical performance of the resultant composite electrode is substantially enhanced. Specifically, the rate capability and capacitance retention are improved by ∼48.2 and ∼33%, respectively, which are 89.8% at 0.8–40 mA/cm2 and 93% after 3000 charge/discharge cycles at 2.0 mA/cm2, respectively. Moreover, the specific capacitance is increased by ∼6 times of that of the MnO2@PEDOT NW electrode at ∼200 mA/cm2. We find that a nanoporous conducting nanowire network that encapsulates a MnO2 nanoparticle layer can provide efficient electron and ion transport paths and stabilize the structure of MnO2 from collapse during charge/discharge cycling and mechanical deformation. This strategy can be applied to other pseudocapacitive material-based electrochemical electrodes, such as transition-metal oxides and conducting polymers.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Min Jiang,Furui Hu,Guifen Feng,Hongguang Zhang,Huayu Hu,Tao Gan,Zuqiang Huang,Yanjuan Zhang
The catalytic oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) to prepare 2,5-furandicarboxylic acid (FDCA) is a promising route to produce biomass-based functional materials. It is significant to develop non-noble metal-based catalysts for efficient conversion of HMF to FDCA. In this study, a facile and green technology was developed to prepare hierarchical porous carbon foam (CF)-supported MnO 2 (MnO 2 /CF) catalyst by in-situ growth of MnO 2 nanoparticles on blocky CF, and the catalytic activity of MnO 2 /CF for the oxidation of HMF to FDCA was evaluated. Under mild reaction conditions, the MnO 2 /CF catalyst achieved 99.8% conversion of HMF and 97.0% yield of FDCA, which was well beyond the catalytic performance of single MnO 2 . The results indicated that the CF with hierarchical porous structure and oxygen-containing groups could facilitate the diffusion of reactant molecules and regulate the crystal structure and morphology of MnO 2 . The synergistic interaction of CF and MnO 2 effectively enhanced specific surface area, surface acid-base sites, oxygen vacancy concentration, and charge transfer efficiency of MnO 2 /CF composite, contributing to favorable catalytic performance. Additionally, the MnO 2 /CF catalyst showed promising stability and reusability. This work provides new insights into the development of efficient, stable, and economical non-noble metal-based catalysts for catalytic conversion of biomass-based chemicals.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Yiran Xiong,Langlang Wang,Ping Ning,Jianfei Luo,Xiang Li,Li Yuan,Yibing Xie,Yixing Ma,Xueqian Wang
The rational design of catalyst structures holds paramount significance for realizing efficient catalytic reactions. In this study, an Fe 3 O 4 @MnO 2 core–shell catalyst was successfully synthesized using a facile one-pot method and applied in the selective oxidation of H 2 S in blast furnace gas. The introduction of the MnO 2 shell suppressed the further growth and aggregation of Fe species, leading to outstanding catalytic stability. Simultaneously, abundant oxygen vacancies facilitated the adsorption and activation of oxygen, thereby enhancing H 2 S oxidation. Experimental results revealed that the Fe 3 O 4 @MnO 2 catalyst (Fe/Mn = 4:1) displayed 100 % H 2 S conversion and 95.7 % sulfur selectivity at 150 °C in a humid gas stream containing O 2 and CO. Remarkably, no discernible decline in catalytic activity was observed after 170 h of operation, indicating the promising industrial prospects of this catalyst. This study provides an effective strategy for designing efficient and stable desulfurization catalysts.
研究领域:
材料科学
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环境工程
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS & DESIGN
·
2021
·
IF 7.991
Lu Gan,Xingyu Fang,Lijie Xu,Linjie Wang,Ying Wu,Boren Dai,Wen He,Jiangtao Shi
In this study, kenaf carbon fiber (KCF) was prepared via direct pyrolysis of kenaf fiber. Afterwards, the prepared KCF was incorporated with δ-MnO 2 to prepare a series of δ-MnO 2 /KCF composites. The as-prepared composites were then used to degrade bisphenol A (BPA) in water via oxidative catalysis. Significantly enhanced oxidative capability of the δ-MnO 2 /KCF was realized, since the KCF could not only prevent δ-MnO 2 aggregation, but also facilitate electron transferring between δ-MnO 2 and BPA. The impacts of catalyst dosage, initial pollutant concentration, solution pH value, temperature, Mn 2+ and natural organic matters on the performance of the δ-MnO 2 /KCF composites were examined in detail. The results showed that 0.025 mM of BPA could be completely degraded within 10 min by 0.5 g/L of the catalyst at the pH value of 3.80. The subsequent LC-MS analysis results indicated that the δ-MnO 2 /KCF initiated BPA oxidative degradation and mineralization through capturing one electron from the BPA molecules and forming BPA radicals. Moreover, the as-prepared δ-MnO 2 /KCF composites also had promising long-time use stability and reusability. This study demonstrates a potentially applicable and sustainable biochar support which could enrich the performance of a catalyst for refractory organic contaminant removals in aqueous environment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2024
·
IF 8
Huai Yang,Xiao-Shuai Zhang,Kai Cheng,Bo Liu,Wei Chen,Jin-Xuan Fan,Yuan-Di Zhao
Low cost and rapid detection of glutathione (GSH) has important clinical reference value for the diagnosis and treatment of related diseases. In this study, a one-step method for rapid detection of GSH is developed based on the characteristics of low cost, simple operation and rapid color development of pregnancy test strip. In this method, magnetic Fe 3 O 4 -doped MnO 2 nanosheet is first synthesized, and colloidal gold probe modified with hCG and ssDNA is absorbed on the surface of the nanosheet. Based on the oxidase-like properties of MnO 2 nanosheet, in the presence of GSH, a redox reaction between GSH with MnO 2 occurs to release hCG signal probe into the solution. The supernatant solution is loaded on pregnancy test strip after magnetic separation, and the test line develops color. Then the smartphone App developed in our lab is used to quantitatively detect GSH. The results show that under the optimal conditions, the GSH in the range of 40~800 μM has a good linear relationship with the color intensity of the test line on pregnancy test strip and the detection limit for GSH is 40 μM. So, this method can realize the detection of GSH with low cost, simple, rapid and sensitive, and it can meet the requirements of GSH detection in actual samples.
研究领域:
分析化学
·
生物传感器
·
即时检测
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 25
·20542-20550
·
IF 3.289
Renjie Li,Lifen Liu,Yuehua Zhang,Fenglin Yang
In this paper, nanoscale MnO2 particles were attached onto the surface of a PVDF flat sheet membrane, step by step, first through dispersion of graphene oxide (GO) in the PVDF membrane, then reduction of immobilized GO by hydroiodic acid and further micro-wave assisted oxidation of RGO (reduced graphene oxide) by KMnO4 and formation of MnO2 on GO. The SEM observation revealed an asymmetric structure with a finger-like transition layer dominating the membrane of PVDF/MnO2. The uniform distribution of MnO2 on the membrane is revealed by EDX and XPS analysis. The attached MnO2 endowed the membrane with high adsorption capacity for aqueous Ni(II). The adsorption was spontaneous and endothermic, fitting a pseudo-first-order kinetic model and Freundlich isotherm model well. The pure water flux and stable permeation flux of the PVDF/MnO2 membrane reached 31.2 L m−2 h−1 and 9.0 L m−2 h−1 under 0.1 MPa, which were 2.3 and 2.6 times those of the PVDF membrane. The analysis of the fouling resistance and flux recovery ratio indicated that the PVDF/MnO2 membrane had better antifouling properties than the PVDF membrane, attributed to the changes of membrane morphologies and surface hydrophilicity. The PVDF/MnO2 membrane had a high removal ratio (≥87.4%) of Ni2+ in dynamic adsorption. Meanwhile the Ni(II) adsorbed membrane could be easily regenerated by a 0.1 M HNO3 solution.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL PAPERS
·
2025
·
IF 2.5
Wang Jiahui,Yu Chen,Yu Yifei,Jiang Xueqin
Antibiotic contaminants such as tetracycline hydrochloride (TC) in landscape water of elderly communities threaten health. Antibiotics degradation in water purification leads to better environment. TC degradation by heterojunction nanocomposite for activating peroxymonosulfate (PMS) is significant. Here, MnO 2 /BiVO 4 nanocomposite catalysts were prepared by sonication and heat treatment. MnO 2 particles with 6–8 nm of size were uniformly distributed on BiVO 4 to favor rapid recombination of electron/hole pairs to improve the efficiency of PMS activation. Photocatalytic system with MnO 2 /BiVO 4 nanocomposite catalyst achieved efficient TC degradation. Optimal TC degradation conditions were [catalyst] = 0.2 g, [PMS] = 0.15 g and pH = 7. Electron paramagnetic resonance (EPR) and scavenger studies verified the occurrence of ·OH, SO 4 ·− , 1 O 2 , h + , ·O 2 − and e − species and positive contribution of MnO 2 /BiVO 4 nanocomposite to PMS activation. MnO 2 /BiVO 4 nanocomposite exhibits good reusability in catalytic reactions. This work provides suitable photocatalytic materials for TC treatment in senior community landscape water.
研究领域:
环境科学
·
材料科学
·
生物学
✓ 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）