查找使用阿拉丁产品的科研文献

Near-surface reconstruction strategy stabilizing high-voltage redox reactions in single crystal Li-rich Mn-based oxides

Huan Zhou,Wenhua Cheng,Qingcui Liu,Wei Wang,Weilu Zhang,Zhouliang Tan,Juan Ding,Yudai Huang

Li-rich Mn-based oxides (LRMO) greatly increase its output energy density due to its additional oxygen redox activity. However, the inherent oxygen loss and irreversible phase transition induce low initial coulombic efficiency and serious voltage decay, further seriously impeding its industrial application. Herein, a near-surface in-situ reconstruction strategy has been proposed, which constructs the oxygen vacancies and spinel phase coating on the surface of single-crystal Li-rich Mn-based oxide (SC-LRMO) concurrently to improve Li + storage performance via the oxalic acid induction method. Intensive exploration based on structure characterizations demonstrates that such a near-surface in-situ reconstruction strategy not only accelerates the transmission of Li + , but also stabilizes high-voltage redox reactions by trapping the escaping O n− within the newly formed spinel phase coating. Impressively, the modified sample exhibit 91.1% capacity retention ratio after 300 cycles, superior to the SC-LRMO (74.5% capacity retention ratio after 300 cycles). Additionally, even at a high cut-off voltage of 5 V, the acid etched sample exhibits significantly enhanced cycling stability, delivering 200 mAh g −1 with a 94% capacity retention ratio after 300 cycles. This surface self-reconstruction strategy provides profound insights into regulating the surface structure of LRMO for high-energy-density lithium-ion batteries.

Solvent-Dependent Mn Doping: Profound Effects on Microstructure and Enhanced Photothermal/Photodynamic Performance in W18O49 Diversified System

Xuejiao Li,Yuxiao Wang,Haiyang Fu,Jiamin Cheng,Bo Li,Zilong Xu,Na Fan,Rui Li,Lianwei Shan,Xin Liu,Limin Dong,Hongrui Ji,Piaoping Yang

The development of efficient photothermal therapy (PTT) and photodynamic therapy (PDT) agents is crucial for overcoming the limitations of traditional cancer treatments, such as the need for single wavelength and the limited penetration depth of excitation light. The tumor microenvironment (TME), characterized by low oxygen levels and an overabundance of endogenous hydrogen peroxide (H2O2), further complicates the therapeutic efficacy. In this study, we synthesized a series of Mn-doped W18O49 materials using a one-step solvothermal method, systematically varying the solvents with n-propanol and isopropanol and manganese doping levels. The effects of solvent type and doping amount on crystal structures, morphology and photo conversion performance were investigated in detail. Under single-wavelength near-infrared (NIR) irradiation at 808/1064 nm, the synthesized materials demonstrated simultaneous hyperthermia and singlet oxygen (1O2) generation, enabling both PTT and PDT. Notably, the Mn-doped W18O49 materials accumulated in the TME could catalyze the conversion of H2O2 into O2, thereby enhancing the production of 1O2 and resulting in a self-amplifying therapeutic effect. This synergistic enhancement of PTT and PDT was further corroborated by in vitro studies, which showed significant inhibitory effects on cancer cell proliferation. Our findings demonstrate that solvent-dependent Mn doping profoundly affects the microstructure and phototherapeutic performance of W18O49 materials, providing a novel strategy for developing advanced PTT/PDT agents activated by single NIR irradiation and responsive to the TME.

AI-driven Cu/Mn-CeO2 nanozyme-functionalized paper-based biosensor for quantitative monitoring of alternariol in food

Siyu Wen,Jiale Cheng,Zuting Yan,Yiru Wang,Yongwei Shi,Yuhan Sun

The lack of rapid, user-friendly methods for alternariol (AOH), a prevalent emerging mycotoxin, presents a considerable analytical challenge. This work introduces an integrated sensing strategy advancing from classical homogeneous liquid-phase detection to a portable AI-enhanced paper-based biosensor. The system employed a Cu/Mn-CeO 2 nanozyme as signal generator and amplifier, and exploited the inhibitory effect of AOH on acetylcholinesterase (AChE) to suppress the thiocholine (TCh)-mediated reduction of oxidized 3,3′,5,5′-tetramethylbenzidine (oxTMB), enabling quantitative colorimetric readout. It achieved ultra-sensitive detection in the liquid phase with a limit of detection (LOD) of 0.016 pg/mL. By incorporating an aptamer affinity column for sample cleanup, the assay was transferred to a foldable paper platform. An AI-driven Monte Carlo color analysis method addressed issues of color heterogeneity and subjective interpretation, yielding an LOD of 0.12 μg/kg in wheat. This study provides a point-of-need solution for AOH screening and establishes a generalizable framework for detecting contaminants in complex samples.

Redox on Mn-Ce interface and its effects on low temperature selective catalytic reduction for NOx removal

Fengyuan Liu,Junqi Li,Hong Yong Sohn,Chaoyi Chen,Jian Yang,Xudong Liu,Yuanpei Lan,Wei Zhang,Qin Wang,Li Liu

The objective of this work was to clearly elucidate the interactions on Mn-Ce interface and understand how they affect low temperature selective catalytic reduction (SCR) for NO x removal. In this work, three Mn-Ce catalysts in similar particle size and morphology with different Mn-Ce interface areas were prepared. MnO 2 @CeO 2 -F had the tightest and largest amount of Mn-Ce interfaces compared with MnO 2 @CeO 2 -P and MnO 2 -CeO 2 -M, and also exhibited the highest NO conversion degree at 100–150 °C as well as the strongest activity of Mn species and lowest generation of N 2 O. The TG-DTG, XPS and electrochemical impedance spectroscopy results proved the redox of Ce 4+ + Mn 3+ ↔ Ce 3+ + Mn 4+ on the Mn-Ce interface, and MnO 2 @CeO 2 -F had the highest Mn 4+ , Ce 3+ , O α concentrations. The results of the study on the redox reactions during the NH 3 -SCR process provided powerful evidence of the Mn 4+ /Mn 3+ and Ce 3+ /Ce 4+ recycles that are important for low temperature NH 3 -SCR process. Moreover, the Mn-Ce interface was directly proved to benefit the surface acid sites, redox ability, and activity of the adsorbed intermediates. Both the Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) reaction mechanisms were observed in the SCR reaction with prepared Mn-Ce materials, where “fast SCR” can be observed with MnO 2 @CeO 2 -F. Moreover, the Mn-Ce interface also lowers the activation energy of the low-temperature SCR process, with MnO 2 @CeO 2 -F having the lowest activation energy. The results from this work offered powerful evidences for the interactions of Mn/Ce redox at the Mn-Ce interface and elucidated clear understanding of the effects of Mn-Ce redox on low-temperature SCR process, which is expected to promote the NO x removal process.

Two inorganic-organic hybrid complexes based on Mn(II) and Bi(III): Synthesis, crystal structure, and properties

Si-Hui Tan,Zhao-Hui Chen,Xi Jiang,Guo-Qing Zhong

Two manganese(II) and bismuth(III) complexes of the formulae [Mn(H 2 O) 6 ]·H 2 bptc ( 1 ) and (H 2 bipy) 2 [Bi 2 Cl 10 ]∙2H 2 O ( 2 ) (H 4 bptc = 3,3′,4,4′-biphenyltetracarboxylic acid, bipy  = 4,4′-bipyridine) were synthesized. The complexes were characterized by elemental analyses, single-crystal X-ray diffraction, powder X-ray diffraction, infrared spectra, and thermal analyses. Structurally, 1 is a mononuclear complex with a triclinic space group P 1 ‾ . 2 is a dinuclear complex and it is built of two Bi 3+ ion cores bridged through two Cl − ions. Furthermore, the result of fluorescence showed that 1 had fluorescent property. And the nanometer manganese oxide was prepared using 1 as a precursor. In addition, the photocatalytic activity of 2 on the degradation of Rhodamine B (RhB) was investigated and a possible photocatalytic mechanism was proposed.

Fabrication of Co-Fe-Mn composites with a mixed-dimensional structure for applications in high-performance supercapacitors

Haiying Li,Shishuai Sun,Wen Cui,Xiaolan Li,Chuanjia Kou,Zhihui Xu,Zhihui Zhang

Reasonably regulating the dimensionality and interface of an electrode material can effectively improve its surface chemical reactivity, charge transfer rate, and ion transport performance, which is crucial to solving several problems with supercapacitors , including low energy density and poor cycle stability. The multidimensional hybrid morphology of Co-Fe carbonate hydroxide (CH) coupled with Co-Mn layered double hydroxide (LDH) is generated directly on the nickel foam substrate by a two-stage process. The prepared multidimensional hybrid materials with pore morphology with the synergistic effect of 1D nanorods , 2D nanosheets , and 3D “porous coral” not only ensure sufficient contact between the electrolyte and electrode material but also enhance the charge transfer and ion diffusion of the electrolyte. The strong coupling effect of Co, Fe, and Mn metals between the heterojunction surface can produce various ionic valence states and high conductivities, resulting in increased redox activity, which thus improves the electrochemical performance. The results of the electrochemical performance test show that when the current density is 10 mA cm −2 , the high area-specific capacitance of 7.33 F cm −2 is two times (3.85 F cm −2 ) that of a Co-Fe CH electrode and five times that of a Co CH electrode. The quasi-solid state asymmetric supercapacitor with a Co-Fe-Mn positive electrode and an active carbon negative electrode displays an energy density of 0.723 mWh cm −2 at a power density of 8.53 mW cm −2 . After 5500 cycles, the apparatus exhibits 101.72 % of the initial capacitance, which can effectively drive small electrical appliances. The results indicate that the supercapacitor exhibits excellent cycle stability and application potential in energy storage.

Glucose oxidase immobilization on Hemin@PCN-222 (Mn): Integrated biomimetic and bioenzyme activities in cascade catalytic process

Peide An,Defeng Hu,Yide Han,Hao Meng,Xia Zhang

On accounting of the structure advantages of MOFs in the enzyme mimics and enzyme immobilization, in this work, the Hemin@PCN-222 (Mn) is constructed through an in-situ hydrothermal route by covalently bonded the –COOH of Hemin with the Zr(IV) of PCN-222 (Mn). With the help of the synergistic effects, the resulting Hemin@PCN-222 (Mn) represents excellent peroxidase-like activities in comparison with the single Hemin and PCN-222 (Mn) with a special enzyme activity of 6.71 U mg −1 . The Hemin@PCN-222 (Mn) was then employed as a carrier to immobilize the glucose oxidase (GOx), the immobilization conditions were optimized. Based on that, the optimized GOx@hemin@PCN-222 (Mn) was applied in the following cascade reaction: the glucose oxidation in the presence of oxygen catalyzed by the immobilized GOx firstly, and then the produced H 2 O 2 worked as an oxidant to oxidize ABTS. The quantity of produced ABTS + was monitored to assess the catalytic efficiency, and the contrast experiments were conducted over the mixture of the natural GOx and HRP. The above cascade process could also be used to detect the glucose, and the detection limit is determined. The high efficiency and the stability of the resulting GOx@hemin@PCN-222 (Mn) highlights the prospect applications of the MOFs-based enzyme mimics in the bio-catalysis and biosensing.

Preparation and Performance of Carbon-Based Ce-Mn Catalysts for Efficient Degradation of Acetone at Low Temperatures

Tong Li,Zhibo Wang,Yue Shi,Xiaolong Yao

Based on the porous carbon material from citric acid residue, catalysts of different Ce-Mn ratios were prepared with incipient-wetness impregnation (IWI) to delve into their acetone-degrading performance and relevant mechanisms. When the Ce-Mn molar ratio is 0.8, the prepared catalyst Ce0.8-Mn/AC shows abundant and uniformly dispersed Mn and Ce particles on the surface. The content of Mn and Ce on the Ce0.8-Mn/AC surface reaches 5.64% and 0.75%, respectively. At the acetone concentration of 238 mg/m3(100 ppm), the laws of acetone degradation in different catalysts at different catalyzing temperatures and with various oxygen concentrations were studied, and we found that the rate of acetone degradation by Ce0.8-Mn/AC can exceed 90% at 250 °C. Cerium oxide and manganese oxide are synergistic in the catalytic degradation of acetone. Adding cerium to manganese-based catalysts can increase the oxygen migration rate in the catalysts and thus raise the reduction rate of lattice oxygen in manganese oxide. The results offer new ideas and approaches for the efficient and comprehensive utilization of bio-fermentation by-products, and for the development of cheap and high degradation performance catalysts for acetone.Keywords:acetone;Ce0.8-Mn/AC;efficient degradation;low temperatures

A multichromatic colorimetric detection method for Vibrio parahaemolyticus based on Fe3O4-Zn-Mn nanoenzyme and dual substrates

Wenteng Qiao,Luliang Wang,Kun Yang,Yushen Liu,Quanwen Liu,Feng Yin

What is the role of Mn/Al/Pt for ZSM-11 being a good catalytic oxidation catalyst?

Qingjun Yu,Wenjing Wu,Jinghui Wei,Jie Zhang,Shunzheng Zhao,Xiaolong Tang,Honghong Yi

Catalytic combustion is one of the most effective technologies applied to volatile organic compounds (VOCs) emission control, in which zeolites have been regarded as a unique support or even a catalyst due to their unique shape & size features as well as the interaction between the zeolitic structural groups and the extraneous metal species. Particularly, Mn-based zeolites have attracted great attention as a promising catalyst for their superior redox ability on account of mixed valent properties. In this work, a series of Mn-contained samples with different compositions were synthesized to investigate the role of Al and Mn in zeolite for catalytically combusting VOCs. As redox active sites, Mn is well dispersed in the form of oligomeric Mn oxide clusters on the surface to optimize catalysis. With Al and Mn introduced into zeolite simultaneously, more defects for the activation of adsorbed oxygen appeared on superficial MnO x , but Al prevented Mn being incorporated in ZSM-11(MEL) distinctly, which is a principal factor affecting the catalytic activity . Additionally, Pt was introduced to further enhance the catalytic performance, whose function in Mn-MEL was also clarified in detail via XPS and other characterization techniques. Results demonstrated that appropriate Mn/Pt ratio could create suitable surface morphology (the interface of Pt-MnO x ) for the adsorption of oxygen species via the synergistic catalytic effect caused by Pt and Mn.

Mn-Enhanced Cobalt Silicate-Activated Peroxymonosulfate for Tetracycline Degradation: Inheriting Merit and Offsetting Deficiency of Oxygen Vacancies

Linlin Su,Lulu Long,Wending Wang,Zhenshuang Kuang,Xinyu Zhou,Chao Chen,Min Xu,Yan He,Gang Yang

Recently, the merits of Vo in catalytic areas were studied in detail, and the deficiency of Vo has also attracted much attention. However, when exploring the enhanced mechanism of bimetals for PMS activation, the effect of bimetals on the deficiency of Vo was usually ignored, especially in some Vo-rich bimetallic systems. Herein, the Co–Mn bimetallic silicate system was constructed to elucidate the effect and mechanism. MnCoSi has an edge over CoSi in the degradation performance of TC (0.02325 min–1 up to 0.07952 min–1). The result was assignable to the fact that the introduction of Mn brought more Vo and enhanced the positive effect of Vo. More importantly, the formation of heterogeneous active sites enhanced the adsorption of metal sites to PMS and compensated for the deficiency of Vo. This study enriched the enhancement mechanism of bimetallic systems and provided a theoretical basis for the optimization of catalysts rich in Vo.

Enhanced PMS Activation by Highly Dispersed Mn-Ce Bimetallic Oxide on Carbon Nanotubes for Degradation of Phenol

Jing Wang,Quanfeng Wang,Pei Gao,Da Sun,Libo Jin,Li Ma,Lan Yang,Jujiao Zhao

Peroxymonosulfate (PMS) activation is an intriguing technology for refractory organic pollutant removal in wastewater treatment. Herein, a highly dispersed Mn-Ce bimetallic oxide on carbon nanotubes (MCC) was synthesized and applied to catalyze PMS for the degradation of phenol. The material was well characterized using a transmission electron microscope (TEM), N2adsorption–desorption isotherms, X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The synthesized MCC showed superior activity for PMS activation. Thekvalue of phenol removal with MCC is 0.135 min−1, which is greatly superior to that of CNT (6.17 × 10−5min−1) and Mn-Ce bimetallic oxide (3.18 × 10−4min−1). Electron paramagnetic resonance (EPR), along with radical quenching experiments, revealed that the activation of PMS by MCC for phenol degradation involves both radical and non-radical reaction pathways. Moreover, a synergic effect between Mn-Ce bimetallic oxide and CNT was identified to be responsible for the outstanding catalytic activity.Keywords:PMS activation;Mn-Ce bimetallic oxide;CNT;synergic effect