Chemosensors
·
2023
·Vol. 11
·期 9
·482
·
IF 4.2
Chunmao Zhu,Qi Wu,Fanshu Yuan,Jie Liu,Dongtian Wang,Qianli Zhang
In this paper, a MnO2nanowire (MnO2-NW) modified carbon paper electrode (CP) was developed as a novel electrochemical sensor for the sensitive determination of tetrabromobisphenol A (TBBPA). The MnO2nanowire was prepared by a hydrothermal synthesis method, and the morphology and structure of MnO2were characterized using scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The electrochemical performance of TBBPA on MnO2-NW/CP was investigated by cyclic voltammetry, and the result confirmed that MnO2-NW/CP exhibited excellent sensitivity for the determination of TBBPA due to the high specific surface area and good electrical conductivity of the nanowire-like MnO2. Moreover, the important electrochemical factors such as pH value, incubation time and modified material proportion were systematically studied to improve the determination sensitivity. The interferences from similar structure compounds on TBBPA have also been investigated. Under the optimal conditions, MnO2-NW/CP displayed a linear range of 70~500 nM for TBBPA with a detection limit of 3.1 nM. This was superior to some electrochemical methods in reference. The work presents a novel and simple method for the determination of TBBPA.
研究领域:
分析化学
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环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2023
·
IF 6.2
Shuofeng Li,Fangfang Wang,Bin Zhao,Chun Wang,Zhi Wang,Qiuhua Wu
Aflatoxin B1 (AFB1) with tremendous toxic effects has caused a serious threat to food security. Accurate quantification of AFB1 in food can effectively prevent the risk of human intake of AFB1. Herein, a colorimetric and fluorescent dual-mode aptasensor for accurate and sensitive detection of AFB1 has been developed based on MnO 2 nanoflowers (MnO 2 NFs) for the first time. MnO 2 NFs could catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) into blue oxidation product (TMBox) by H 2 O 2 , which would be used for visible detection of AFB1. Simultaneously, MnO 2 NFs can be served as a signal amplifier and reduced by ascorbic acid to generate lots of Mn 2+ which would quench the fluorescence of calcein for fluorescent detection of AFB1. Both colorimetric and fluorescent methods have been successfully applied for determination of AFB1 in milk samples with satisfactory results. The proposed dual-mode detection method with high detection sensitivity and accuracy showed great promise for monitoring AFB1 in food.
研究领域:
食品安全
·
分析化学
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生物传感
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Xue Shi,Bao Zhang,Liangliang Liu,Yifei Zhu,Xiaochen Xiang,Sumin Li,Ke Zhao,Wanyu Shang,Guangqin Gu,Junmeng Guo,Peng Cui,Gang Cheng,Zuliang Du
The simultaneous activation of surface lattice oxygen and dioxygen is key to transition metal oxide-based catalytic CO oxidation systems. However, the reaction is difficult at room temperature owing to the high metal–oxygen bond energy. This study presents a triboelectric plasma–transition metal oxide catalytic system driven by a triboelectric nanogenerator, which realizes CO oxidation reaction at room temperature and atmospheric pressure. Among the transition metal oxides evaluated, MnO2 nanostructures exhibited an optimal CO oxidation activity of 0.24 mmol·g–1·h–1 and a low energy consumption converted per mole CO of 6.0 × 103 kJ. For the activation of both surface lattice oxygen and dioxygen, multiple reaction pathways with barriers ranging from 0.37 to 2.43 eV have been revealed by X-ray photoelectron spectroscopy, electron paramagnetic resonance, and density functional theory simulation. These catalytic reaction phenomena have been explained by an extended Mars–van Krevelen mechanism, in which multiple pathways with various barriers were overcome by the electrons in the plasma with a uniform and broad distribution probability. This work provides an efficient strategy for the conversion and utilization of mechanical energy for chemical synthesis.
研究领域:
材料科学
·
催化化学
·
能源转换
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2022
·
IF 6.633
Siyi Wang,Junping Ma,Chen Wang,Wenke Xi,Yuxuan Bai,Wen Lu,Jianjun Wang
To effectively treat the contamination caused by radionuclide uranium (VI) in wastewater discharged from the nuclear industry, it is necessary to investigate novel nanomaterials with powerful adsorption capacities. In this study, a novel composite nanomaterial α-MnO 2 @CTS was successfully synthesized by coating nano manganese dioxide (α-MnO 2 ) with chitosan (CTS) using a straightforward method. The effects of the pH, ionic strength, presence of coexisting ions, time, temperature, cycle number and stability on U(VI) removal were investigated. The results showed that U(VI) elimination by α-MnO 2 @CTS was strongly dependent on the pH but weakly influenced by the NaNO 3 concentration, which indicated complexation on the inner-sphere surface. At pH = 6.0 ± 0.1 and T = 298 K, α-MnO 2 @CTS had an adsorption capacity of up to 326.54 mg/g toward U(VI), which was consistent with the results of a Langmuir adsorption isotherm model. In various studies, the high removal rate of U(VI) by α-MnO 2 @CTS has been attributed to electrostatic attraction, and hydroxyl and amide groups introduced by CTS are also considered to play a key role in the adsorption process. In conclusion, α-MnO 2 @CTS can efficiently and rapidly adsorb U(VI) under acidic conditions, indicating broad application prospects for radioactive wastewater treatment.
研究领域:
环境科学
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纳米技术
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放射性废物管理
✓ 已验证
产品关联
DOI
高影响因子
Carbon Energy
·
2025
·
IF 24.2
Meng Zhang,Ting Xu,Wei Liu,Han Zhang,Junjie Qi,Xuan Wang,Yaxuan Wang,Liyu Zhu,Kun Liu,Junfeng Wang,Chuanling Si
Carbon-based substrates in Zn–MnO 2 flexible batteries have issues of low adhesion to MnO 2 , impacting cycle stability and capacity performance. A triple-synergistic strategy integrating C–O–Mn covalent bonding, wettability optimization, and hierarchical mesoporous engineering via cellulose nanofibers/carbon nanotube (CNF/CNT)-modified carbon cloth (CC) was proposed. This design achieves a “surface-locking” effect between the substrate and electrode materials, which was proven through theory and experiments. Density functional theory (DFT) simulations validate the “surface-locking” mechanism, where oxygen functionalities on CNF can form robust CO–Mn bonds with MnO 2 , inducing an increase in MnO 2 adsorption energy from −0.21 eV (pristine CC) to −1.36 eV, effectively suppressing Mn dissolution. Optimal wettability (contact angle: 97°) reduced Zn 2+ desolvation and water-induced side reactions. Hierarchical pore structures accelerated Zn 2+ diffusion. The optimized CC@CNF 1 /CNT 2 –MnO 2 cathode achieves 92% capacity retention after 2000 cycles at 1 A/g. This study highlights a surface engineering strategy that effectively addresses the individual challenges associated with interfacial adhesion, reaction kinetics, and ion transport. This strategy offers fundamental insights into electrode interface modification for the development of next-generation flexible energy storage systems.
研究领域:
材料科学
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储能
·
电化学
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纳米材料
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柔性电子
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Lei Shi,Xudong Zhou,Yujie Guo,Yunyu Li,Chenxu Yan,Qifeng Han,Lingfan Zhang,Wenqing Zhang
The Mn-based catalysts, with low cost and high activity, are believed to be the effective composites for eliminating in-door formaldehyde (HCHO), while the powdered form nanosized catalysts are hardly to apply for practical application. Herein, hetero-structure of nanosheets manganese oxide (MnO 2 ) encapsulating N-doping graphene sphere ( GS ) were deposited in network-like sponge for constructing 3D catalyst. The prepared MnO 2 -GS-Sponge composite catalyst exhibited excellent performance for removing HCHO at room temperature compared with GS and commercial MnO 2 . The MnO 2 -GS with larger specific surface area (209.1 m 2 ·g −1 ) was dispersed evenly in 3D network of sponge, which facilitated exposing more activate sites and achieving fast transport kinetics accelerating catalytic reaction for converting 97.1 % of 100 ppm of HCHO continuously to CO 2 for 120 h. Moreover, rely on the chemisorption of amino groups on N-doping GS surface, HCHO could be enriched even at low concentrations and efficient elimination (from 1000 ppb to12 ppb, at 35 ℃ in 48 h). The average oxidation state and infrared spectra analysis suggested that abundant oxygen vacancies on MnO 2 -GS-Sponge could be identified as surface-active sites of converting HCHO into the intermediates of dioxymethylene and formate. This work might inspire the designing 3D composite material for potential application in other fields of environmental engineering or energy industrial.
研究领域:
环境工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Changwei Bai,Gang Yang,Shirong Zhang,Shihuai Deng,Yanzong Zhang,Chao Chen,Jingsong He,Min Xu,Lulu Long
A novel electrocatalytic anode (ECA)/α-MnO 2 /peroxymonosulfate (PMS) synergistic system was developed and evaluated for the removal of combined tetracycline (TC) and hexavalent chromium (Cr(VI)) pollution from waste waters. The factors affecting the efficiency of the removal of the combined pollutants, such as the synthesis time of the electrode, the amounts of raw materials, the PMS dose, the voltage, the initial pH and the coexisting ions were investigated. The breakdown products of PMS in the ECA/α-MnO 2 /PMS system improved the conductivity of the solution and the electrical current promoted the conversion of the valence state of Mn ions, resulting in a synergistic effect between the ECA and PMS activation processes, which improved the efficiency of removal of TC. The cathode chamber was fully utilized to simultaneously reduce Cr(VI). Synergistic effects occur in the ECA/α-MnO 2 /PMS system in appropriate ranges of the voltage or PMS dose, although the efficiency of the removal of TC depends mainly on the electrical current in the system. Both hydroxyl (•OH) and sulfate (SO 4 •− ) radicals played important parts in the degradation of TC. The main degradation products of TC were identified and degradation pathways proposed. The synergistic effects between the ECA process and a Fenton-like process was studied, providing a new approach for the study of electro-Fenton technology and the removal of combinations of TC and Cr(VI) from waste waters.
研究领域:
环境科学
·
污染控制
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电化学技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 12
·6801-6806
·
IF 3.119
Pengyu Xiao,Yang Liu,Wenjing Zong,Jin Wang,Minghuo Wu,Jingjing Zhan,Xianliang Yi,Lifen Liu,Hao Zhou
Multiple enzyme-like activities of manganese oxides (MnO2) have been reported and applied in catalysis, biosensors, and cancer therapy. Here, we report that catechol can be determined colorimetrically based on the 3,3′,5,5′-tetramethylbenzidine (TMB) oxidase-like activity of δ-MnO2. The detection was based on pre-incubation of catechol containing water samples with δ-MnO2, and then the residual TMB oxidase-like activity of reacted δ-MnO2 was linearly dependent on the catechol concentration in the range of 0.5 to 10 μM. This determination method was stable at pH 3.73–6.00 and was not affected by ion strength up to 200 μM. Common co-solutes in water bodies (50 μM) have negligible effects and excellent selectivity of catechol among various phenolic compounds (15 μM) was facilitated. Both reduction and aggregation of δ-MnO2 were observed during the incubation process with catechol, and aggregation-induced TMB oxidase–mimic activity decrease was the main factor for this colorimetric determination.
研究领域:
分析化学
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环境科学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
ACS Nano
·
2021
·
IF 15.881
Xiaodong Zhu,Ziyi Cao,Wenjie Wang,Haijing Li,Juncai Dong,Shangpeng Gao,Dongxiao Xu,Lei Li,Jianfeng Shen,Mingxin Ye
Mn-based aqueous zinc-ion batteries (ZIBs) are promising candidate for large-scale rechargeable energy storage because of easy fabrication, low cost, and high safety. Nevertheless, the commercial application of Mn-based cathode is hindered by the challenging issues of low rate capability and poor cyclability. Herein, a manganese–vanadium hybrid, K–V2C@MnO2 cathode, featured with MnO2 nanosheets uniformly formed on a V2CTX MXene surface, is elaborately designed and synthesized by metal–cation intercalation and following in situ growth strategy. Benefiting from the hybrid structure with high conductivity, abundant active sites, and the synergistic reaction of Mn2+ electrodeposition and inhibited structural damage of MnO2, K–V2C@MnO2 shows excellent electrochemical performance for aqueous ZIBs. Specifically, it presents the high specific capacity of 408.1 mAh g–1 at 0.3 A g–1 and maintains the specific capacity of 119.2 mAh g–1 at a high current density of 10 A g–1 in a long-term cycle of up to 10000 cycles. It is superior to almost all reported Mn-based cathodes for ZIBs in the aqueous electrolyte. The superior electrochemical performance suggests that the Mn-based cathode materials designed in this work can be a rational approach to be applied for high-performance ZIBs cathodes.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
·
IF 8.9
Yanyi Liu,Wenhuan Yuan,Wenli Lin,Shan Yu,Lei Zhou,Qingyi Zeng,Jin Wang,Luoheng Tao,Qunwei Dai,Juan Liu
Even though uranium (U) is considered to be an essential strategic resource with vital significance to nuclear power development and climate change mitigation , U exposure to human and ecological environment has received growing concerns due to its both highly chemically toxic and radioactively hazardous property. In this study, a composite (M-BC) based on Ficus macrocarpa (banyan tree) aerial roots biochar (BC) modified by δ-MnO 2 was designed to separate U(VI) from synthetic wastewater. The results showed that the separation capacity of M-BC was 61.53 mg/g under the solid – liquid ratio of 1 g/L, which was significantly higher than that of BC (12.39 mg/g). The separation behavior of U(VI) both by BC and M-BC fitted well with Freundlich isothermal models, indicating multilayer adsorption occurring on heterogeneous surfaces. The reaction process was consistent with the pseudo-second-order kinetic model and the main rate-limiting step was particle diffusion process. It is worthy to note that the removal of U(VI) by M-BC was maintained at 94.56% even after five cycles, indicating excellent reusability and promising application potential. Multiple characterization techniques ( e.g. Scanning Electron Microscope-Energy Dispersive Spectrometer (SEM-EDS), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Brunauer-Emmett-Teller (BET) and X-ray Photoelectron Spectroscopy (XPS)) uncovered that U(VI) complexation with oxygen-containing functional groups ( e.g. O–C O and Mn–O) and cation exchange with protonated ≡MnOH were the dominant mechanisms for U(VI) removal. Application in real uranium wastewater treatment showed that 96% removal of U was achieved by M-BC and more than 92% of co-existing (potentially) toxic metals such as Tl, Co, Pb, Cu and Zn were simultaneously removed. The work verified a feasible candidate of banyan tree aerial roots biowaste based δ-MnO 2 -modified porous BC composites for efficient separation of U(VI) from uranium wastewater, which are beneficial to help address the dilemma between sustainability of nuclear power and subsequent hazard elimination.
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
Molecular Catalysis
·
2020
·
IF 3.687
Yiqing Zeng,Zihua Wu,Lina Guo,Yanan Wang,Shule Zhang,Qin Zhong
The problems of easily inactivated by SO 2 poisoning and high N 2 O formation for MnO x based catalysts hinder its application in selective catalytic reduction (SCR) of NO x with NH 3 . The SO 2 poisoning mechanism has been well demonstrated, but the N 2 O formation mechanism was still controversial due to previous limited study. Herein, MnO 2 supported on MO x (Mn/M, M = Al, Si and Ti) were prepared by wet impregnation method to investigate the carrier effect on the formation of N 2 O. Although all of selected supports had a large amount of surface acid sites, only forming strong active-support interaction can separate the activation sites of NH 3 and NO + O 2 . Accordingly, the activation of NH 3 and NO + O 2 on MnTi was respectively occurred on TiO 2 and MnO 2 , but both NH 3 and NO + O 2 was activated on MnO 2 over MnAl and MnSi samples. The over-activation (NH 2 dissociated into NH) of NH 3 would be effectively inhibited when NH 3 activation was occurred on TiO 2 , thus it can significantly suppress the formation of N 2 O. In contrast, the NH 3 species would sharply decompose into NH on MnO 2 and then lead to the high amount of N 2 O. Finally, we proposed some methods that might effectively improve the selectivity of MnO x- based catalysts.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 14
·6747-6755
·
IF 8.867
Can Cao,Jian Xie,Shichao Zhang,Bin Pan,Gaoshao Cao,Xinbing Zhao
Lithium–oxygen (Li–O2) cells are receiving intense interest because of their extremely high energy density. A highly efficient catalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is a key factor influencing the performance of lithium–oxygen cells. In this work, we prepared a highly efficient CeO2-decorated δ-MnO2 (CeO2/δ-MnO2) catalyst which is composed of graphene-like δ-MnO2 with ultrafine CeO2 nanocrystals decorated on it. Li–O2 cells with the CeO2/δ-MnO2 catalyst exhibit superior electrochemical performance, including high discharge specific capacity (8260 mA h g−1 at 100 mA g−1), good rate capability (735 mA h g−1 at 1600 mA g−1), and excellent cycling stability (296 cycles at a limited capacity of 500 mA h g−1), which is much better than that with a bare δ-MnO2 catalyst. The achievement of excellent electrochemical performance is attributed to the highly efficient co-catalytic ability of δ-MnO2 and CeO2 and the desirable graphene-like architecture of the CeO2/δ-MnO2 catalyst, as well as the formation of the thin-layered discharge product Li2O2.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）