CERAMICS INTERNATIONAL
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2024
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IF 5.1
Xiao Li,Yuan-Zhuo Tan,An-Ran Xue,Zhuo Wang,Yuan-Ru Guo,Qing-Jiang Pan
In research out of the sustainable electrochemical energy storage material , NiCo-LDH/MnO 2 composite has been prepared via simple hydrothermal method . The experimental characterizations of XRD , SEM/TEM and XPS have been utilized to explore the structure and morphology of prepared composite. The needle-like MnO 2 was found adhered to NiCo-LDH sheet. The composite's electrochemical properties were evaluated through cyclic voltammetry , galvanostatic charge-discharge and electrochemical impedance spectroscopy . It has been realized that the MnO 2 dosage not only changes the composite's microstructure but also affects its electrochemical properties. The best specific capacitance (2602 F g −1 at a current density of 1 A g −1 ) was achieved for the composite sample with 38% MnO 2 (mass), which is almost two times high from the same composite in previous reports. With the sample, the assembled asymmetric supercapacitor exhibits a remarkable energy density of 19.56 Wh . Kg −1 at 800.29 W Kg −1 . It could be attributed to the synergetic effects of two components as well as their good interfacial coupling. The good electrochemical activity makes our synthesized composite feasible to be applied as electrode material and provides valuable insights for the development of smart capacitors utilizing NiCo-LDH.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Zimo Lou,Jiasheng Zhou,Mei Sun,Jiang Xu,Kunlun Yang,Dan Lv,Yaping Zhao,Xinhua Xu
A Pd/MnO 2 /Ni foam electrode with hierarchical structure was synthesized via electrodeposition for efficient electrocatalytic hydrodechlorination. Compared with the ordinary Pd/Ni foam electrode, the introduction of MnO 2 greatly enhanced the catalytic reactivity and reduced the dose of precious metal Pd. Only a quarter of Pd was required for the Pd/MnO 2 /Ni foam compared to the Pd/Ni electrode to achieve complete dechlorination of 2,4-dichlorobenzoic acid (2,4-DCBA) within 120 min. Various characterizations suggested that MnO 2 covered the surface of the Ni foam and increased the specific surface area of the electrode, while Pd nanoparticles were subsequently deposited on MnO 2 . The atomic H ∗ -based indirect dechlorination was the dominant pathway while only approximately 13% of 2,4-DCBA was removed by direct electron transfer. Atomic H ∗ adsorbed on Pd acted as the key active species for the dechlorination of 2,4-DCBA by the Pd/MnO 2 /Ni foam electrode in this study. The introduction of MnO 2 would promote the water dissociation and the hydrogen evolution reaction, and provide Pd with more atomic H ∗ . Pd/MnO 2 /Ni foam exhibited good stability and reusability according to the XPS spectra and consecutive electrocatalytic experiments, which suggested its long-term potential for efficient removal of chlorinated contaminants. This work demonstrated a new strategy to design efficient electrocatalysts with less precious metal.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Communications Chemistry
·
2022
·Vol. 5
·期 1
·1-8
·
IF 7.211
Xu Jiacheng,Zhang Tiantian,Fang Shiyu,Li Jing,Wu Zuliang,Wang Wei,Zhu Jiali,Gao Erhao,Yao Shuiliang
Understanding of the roles of oxygen species at reducible metal oxide surfaces under real oxidation conditions is important to improve the performance of these catalysts. The present study addresses this issue by applying a combination of operando diffuse reflectance infrared Fourier transform spectroscopy with a temperature-programmed reaction cell and mass spectrometry to explore the behaviors of oxygen species during H 2 oxidation in a temperature range of 25–400 °C at β-MnO 2 surfaces. It is revealed that O 2 is dissociated simultaneously into terminal-type oxygen (M 2+ -O 2– ) and bridge-type oxygen (M + -O 2– -M + ) via adsorption at the Mn cation with an oxygen vacancy. O 2 adsorption is inhibited if the Mn cation is covered with terminal-adsorbed species (O, OH, or H 2 O). In a temperature range of 110–150 °C, OH at Mn cation becomes reactive and its reaction product (H 2 O) can desorb from the Mn cation, resulting in the formation of bare Mn cation for O 2 adsorption and dissociation. At a temperature above 150 °C, OH is reactive enough to leave bare Mn cation for O 2 adsorption and dissociation. These results suggest that bare metal cations with oxygen vacancies are important to improve the performance of reducible metal oxide catalysts.
研究领域:
催化化学
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材料科学
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表面科学
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DOI
高影响因子
International Journal of Nanomedicine
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2025
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IF 6.5
Jing Zhang,Min Zha,Shanghua Xiao,Nina Filipczak,Satya Siva Kishan Yalamarty,Xiangping Wu,Chenkai Gong,Xiang Li
Objective Nanoparticles constructed with silver/manganese dioxide (Ag@MnO2) as the core, in conjunction with survivin siRNA (sis) and cyclo(RGD-DPhe-K) (Ag@MnO2-sis-c-L), were prepared for integrated tumor diagnosis and therapy.Methods Ag@MnO2-sis-c-L particles were prepared and characterized. The silver and manganese content were determined by inductively coupled plasma optical emission spectroscopy (ICP-OES). The stability of sis in the system was evaluated by incubation with 50% FBS before the agarose gel electrophoresis experiment. The in vitro photothermal conversion ability, cytotoxicity to 4T1 cells, and cellular uptake of preparations were evaluated. The dialysis technique was employed to determine the in vitro release profile of Ag and Mn from Ag@MnO2-sis-c-L under various pH conditions. The pharmacokinetic behavior and tissue distribution of silver in vivo were detected by ICP-OES. Animal model experiments were conducted to further evaluate the anti-tumor efficacy of Ag@MnO2-sis-c-L against breast cancer in combination with infrared irradiation.Results Our newly synthesized Ag@MnO2-sis-c-L nanoparticles displayed superior physicochemical properties. The combined application of these nanoparticles with photothermal therapy (PTT) exerted the strongest synergistic inhibitory effects on tumor growth. Survivin protein expression in tumor tissues were markedly suppressed following delivery of nanoparticles loaded with sis. Additionally, magnetic resonance imaging revealed the high imaging capability of hybrid nanoparticles.Conclusion This study supports the potential utility of Ag@MnO2-sis-c-L coupled with PTT in therapeutic and diagnostic imaging applications.
研究领域:
纳米医学
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肿瘤学
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生物材料
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分子影像学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
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2025
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IF 4.7
Dong Xu,Quankang Sheng,Ao Chen,Long Chen,Yu Zhang,Chao Zhu,Jian Chen,Shaoyun Chen,Chenglong Hu
Conductive polymers have great potential applications as electrode materials for supercapacitors in small energy storage devices. First, manganese sulfate (MnSO4) was oxidized to manganese dioxide (MnO2) microspheres with a diameter of 1.5–3.5 μm by catalysis of Ag+. Subsequently, polyaniline (PANI) grew in situ on the surface of MnO2 by the dilute solution method, using MnO2 as a self-degraded template in an acidic environment. The MnO2 was gradually reduced to Mn2+ because MnO2 acted as both an oxidant and a template for the polymerization of aniline, resulting in the formation of PANI microspheres with a hollow urchin-like structure. The as-prepared PANI, with its high specific surface area and porous properties, was considered a potential material for surface–interface chemical energy storage. Therefore, the specific capacitance of the hollow urchin-like PANI electrode could reach 531 ± 35 F/g at 5 mV/s, and the loss of specific capacitance was 41.0% when the current density increased from 1 to 10 A/g. Further analysis of the charge storage mechanism of the hollow urchin-like PANI electrode revealed that the electrode was controlled by slow kinetics, indicating that the electrode reaction was mainly controlled by the Faradaic intercalation process inside the active material. A symmetric supercapacitor device was also assembled using hollow urchin-like PANI microsphere electrodes, and the maximum energy density was about 17.92 Wh/kg at a power density of 500 W/kg.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
CHEMOSPHERE
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2021
·
IF 7.086
Jianhui Zhao,Yuanzhou Wang,Ning Li,Shaopo Wang,Junli Yu,Xinxin Li
In this work, the magnetic γ-Fe 2 O 3 –MnO 2 bifunctional catalyst with oxygen vacancy was synthesized for peroxymonosulfate (PMS) activation under visible light. The activity of γ-Fe 2 O 3 –MnO 2 was investigated by ciprofloxacin (cipro) degradation. Results showed that 98.3% of cipro (50 μM) was removed within 30 min in visible-light/PMS system mediated by γ-Fe 2 O 3 –MnO 2 (2:1) with fine-tuned oxygen vacancy. The cipro degradation data fitted well with pseudo-first-order kinetic model with the highest kinetic constant of 0.114 min −1 . Besides, the γ-Fe 2 O 3 –MnO 2 exhibited stability, recyclability and practicability. High selectivity for cipro degradation was observed with coexisting anions in visible-light/γ-Fe 2 O 3 –MnO 2 /PMS system. Furthermore, the enhanced mechanism of PMS activation under visible light with γ-Fe 2 O 3 –MnO 2 was proposed. The appropriate oxygen vacancy enhanced the separation of photo-induced carriers and Z scheme heterostructure maintained the highest redox potential . Accordingly, the synergistic effect of photocatalysis and PMS activation enhanced cipro degradation. Free radical and non-radical species including , h + , 1 O 2 , • OH and co-existed in the coupled system. Impressively, this study provides a handy approach for oxygen vacancy regulation in metallic oxides composite and an easily recycled catalyst with high-activity in coupled oxidation system towards antibiotic degradation.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
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2016
·Vol. 8
·期 19
·3935-3940
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IF 1.915
Shichao Lin,Hanjun Cheng,Qiran Ouyang,Hui Wei
Two-dimensional (2D) nanomaterials (such as 2D MnO2 nanosheets) have received increasing attention due to their unique photophysical properties, rich redox chemistry, excellent colloidal stability, good biocompatibility, etc. Recently, numerous sensing platforms have been reported by exploring the 2D MnO2 nanosheet mediated fluorescence quenching towards fluorophores and/or redox reactions between MnO2 and reductive targets. Though various fluorophores have been used in 2D MnO2 nanosheet based turn-on sensing systems, ultrasmall metal nanoclusters have not been exploited yet. Furthermore, the quenching mechanisms of MnO2 nanosheets towards various fluorophores have remained elusive. To address these issues, we studied the quenching of Au nanocluster fluorescence by 2D MnO2 nanosheets. First, we demonstrated that 2D MnO2 nanosheets were effective quenchers towards the fluorescence of metal nanoclusters (e.g., AuNC@BSA, the bovine serum albumin stabilized Au nanocluster). We further revealed that both dynamic and static quenching effects played critical roles in the quenching process while fluorescence resonance energy transfer (FRET) and inner filter effect (IFE) only played very minor roles in the quenching process. Finally, we developed a turn-on sensing strategy for detection of glutathione (GSH), an important antioxidant with good sensitivity and selectivity. This work provides useful insights in understanding the mechanisms of nanomaterial-induced fluorescence quenching. It also paves a way to design turn-on fluorescent sensors for important reductive targets.
研究领域:
材料科学
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分析化学
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生物医学工程
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2022
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IF 3.841
Xianqiang Song,Xin Chen,Zhaoxiong Liang,Dan Xu,Yong Liang
In this work, we present core/shell Au@MnO 2 nanoparticles-based visual sensing strategy for mercury ion (Hg 2+ ) detection. The MnO 2 shell of Au@MnO 2 nanoparticles catalyzes the oxidation reaction between tetramethylbenzidine (TMB) and oxygen in the air, generating blue derivative (oxTMB) with an absorption peak at 650 nm. Glutathione (GSH) inhibits the formation of oxTMB, reversing the reaction and turning it back into colorless TMB molecules. While in the existence of Hg 2+ , GSH binds to Hg 2+ due to the strong affinity between the Hg 2+ and the -SH, and in this situation, Au@MnO 2 catalyzes the oxidation of TMB to make the solution become blue. Using the colorimetric sensor, the detection limit of Hg 2+ reached as low as 0.473 nM by UV–vis spectroscopy and 1 nM under the naked eye observation, which is lower than toxicity level of Hg 2+ (10 nM) formulated by the U.S. Environmental Protection Agency.
研究领域:
分析化学
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环境科学
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产品关联
DOI
高影响因子
DRUG DELIVERY
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2022
·
IF 6.819
Ziyue Wang,Cuicui Wu,Jinren Liu,Shunxin Hu,Junli Yu,Qiangqiamg Yin,Hongda Tian,Zhipeng Ding,Guiqiang Qi,Li Wang,Liguo Hao
Sorafenib (SRF) presents undesirable effects in clinical treatment, due to the lack of targeting, poor water solubility, and obvious side effects. In this study, we constructed a novel nanodrug carrier system for accurate and efficient delivery of SRF, improving its therapeutic effects and achieving tumor-specific imaging. The hollow mesoporous MnO2 (H-MnO2) nanoparticles equipped with target substance aptamers (APT) on the surface were used to load SRF for the first time. The resulting H-MnO2-SRF-APT could specifically bound to glypican-3 (GPC3) receptors on the surface of hepatocellular carcinoma (HCC), rapidly undergoing subsequent degradation under decreased pH conditions in the tumor microenvironment (TME) and releasing the loaded SRF. In this process, Mn2+ ions were used for T1-weighted magnetic resonance imaging simultaneously. The in vitro cell experiments indicated that H-MnO2-SRF-APT showed much more effects on the inhibition in the proliferation of Huh7 and HepG2 HCC cells than that of the non-targeted H-MnO2-SRF and free SRF. Besides, the in vivo results further confirmed that H-MnO2-SRF-APT could effectively inhibit the growth of xenograft tumors Huh7 in the naked mouse with good biosafety. In conclusion, H-MnO2-SRF-APT could significantly enhance the therapeutic effect of SRF and is expected to be a new way of diagnosis and treatment of HCC.
研究领域:
纳米技术
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药学
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癌症研究
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Zhiquan Chen,Didi Yang,Zhenda Liang,Yongtao Xu,Yijun Pang,Gang Xu,Chaoxiang Chen,Kunyu Ma,Li Zhou,Bing Yan
Microbial pollution and antibiotic contamination can pose a serious threat to human health. The rational development of efficient and low-cost methods is critical to solving these problems. In this study, novel Z-scheme heterojunctions consisting of Yb-MnO 2 and nitrogen-doped carbon quantum dots (N-CQDs) were fabricated to achieve efficient photocatalytic degradation of tetracycline (TC) and the destruction of bacteria ( Escherichia coli used as a model). Results showed that the Yb-doping strategy improves the characteristics of host MnO 2 by weakening the lattice interface and increasing its surface area. Compared with Yb-MnO 2 , Yb-MnO 2 /N-CQDs heterostructures exhibited superior photocatalytic activity in TC degradation under simulated solar light. The remarkable photocatalytic and mild oxidation abilities of Yb-MnO 2 /N-CQDs led to an impressive 97.88% removal rate of TC. Additionally, the structure displayed robust resistance to various ions and broad pH levels. Notably, the Yb-MnO 2 /N-CQDs heterostructures exhibited excellent bactericidal activity, with no observed bacterial resistance even after 20 consecutive trials. Furthermore, quenching experiments demonstrated that 1 O 2 and O 2 − were the primary radicals involved in the Yb-MnO 2 /N-CQDs-based photocatalysis process. The remarkable photocatalytic activity of Yb-MnO 2 /N-CQDs can be attributed to two key factors. Firstly, the large surface area and abundant oxygen defects provide rich active sites for reactant degradation. Secondly, the Z-scheme heterojunctions formed between Yb-MnO 2 and N-CQDs effectively facilitate the separation of photogenerated electron-hole pairs and increase the reduction/oxidation potentials for reactive oxygen species generation. This study presents a promising novel photocatalyst for the facile and energy-saving treatment of antibiotic and microbial pollution, and it may provide new insight into the design of highly efficient heterogeneous photocatalysts.
研究领域:
环境科学
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材料科学
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微生物学
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产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2025
·
IF 3.7
Kang Liu,Shuang Luo,Jianying Liang,Pengfei Xu,Jinglv Feng,Shumin Qin,Jien Li
Graphical A hydrothermal process is used for co-doping Mo and Zn into tunnel-structured MnO 2 (MZMO), enhancing its ion diffusion kinetics and electrical conductivity by introducing impurity energy levels and generating oxygen vacancies. This co-doping strategy also stabilizes the MnO 2 framework, enabling the MZMO cathode to achieve exceptional capacity, highly reversible H + /Zn 2+ co-intercalation, and prolonged cycle life. To address the rising demand for eco-friendly and efficient energy storage devices, rechargeable aqueous zinc ion batteries (AZIBs) are emerging as a promising candidate for large-scale energy storage. α-MnO 2 has attracted extensive attention for its open channels and exceptional Zn 2+ storage capacity. However, the electrochemical performance of α-MnO 2 is significantly hindered by severe structural collapse and sluggish reaction kinetics. Herein, we propose a simple hydrothermal approach for co-doping Mo and Zn into tunnel-structured MnO 2 (MZMO). The ion diffusion kinetics of MZMO are optimized due to ameliorated electrical conductivity by doped cations and introduced oxygen vacancies within the MnO 2 lattice. Moreover, Mo and Zn co-doping stabilizes the MnO 2 framework, significantly enhancing its electrochemical performance during prolonged cycling. Charge storage mechanism analysis further validates the extraordinary stability of the MZMO phase structure during the Zn 2+ /H + co-intercalation and deintercalation. The MZMO cathode demonstrates rapid and reversible Zn 2+ storage, with a high capacity of 395 mAh g −1 at 0.2 A g −1 , and the capacity remains at 136 mAh g −1 after 1000 cycles at 2 A g −1 . This study demonstrates Mo and Zn co-doping is an effective strategy to enhance the electrochemical performance of MnO 2 , offering valuable insights for developing other promising cathodes for AZIBs.
研究领域:
材料科学
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能源存储技术
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
·
IF 10.652
Huixuan Zhang,Li-chao Nengzi,Xiaoling Li,Zhongjuan Wang,Bo Li,Lichen Liu,Xiuwen Cheng
In this study, CuBi 2 O 4 /MnO 2 composite was successfully prepared by a two-step hydrothermal method and served as a low-cost and non-toxic catalyst for photo-Fenton reaction. Meanwhile, several refractory pollutants including ceftiofur (CEF), tetracycline (TC) and lomefloxacin (LOM) could be efficiently eliminated within 40 min. Particularly, the influence of experimental parameters towards CEF degradation were systematically studied in detailed. 93.6% of CEF was decomposed over 40 min with 0.4 g·L −1 PMS and 0.3 g·L −1 CuBi 2 O 4 /MnO 2 at pH 11. After this, active species scavenging experiments were conducted and the results exhibited that sulfate radicals, hydroxyl radicals, holes and superoxide radicals participated in the degradation of CEF. Besides, CuBi 2 O 4 /MnO 2 composite possessed high stability and reusability based on continuous cycle experiments. Moreover, based on the analysis of HPLC/MS, three possible degradation pathways of CEF were put forward and the degradation mechanism of CEF was elucidated.
研究领域:
环境科学
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催化材料
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污染控制
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）