Synergism of preintercalated manganese ions and lattice water in vanadium oxide cathodes for high-capacity and long-life Zn-ion batteries

Aqueous Zn-ion batteries(AZIBs)are recognized as a promising energy storage system with intrinsic safety and low cost,but its applications still rely on the design of high-capacity and stable-cycling cathode materials.In this work,we present an intercalation mechanism-based cathode materials for AZIB,i.e.the vanadium oxide with pre-intercalated manganese ions and lattice water(noted as MVOH).The synergistic effect between Mn^(2+)and lattice H_(2)O not only expands the interlayer spacing,but also significantly enhances the structural stability.Systematic in-situ and ex-situ characterizations clarify the Zn^(2+)/H^(+)co–(de)intercalation mechanism of MVOH in aqueous electrolyte.The demonstrated remarkable structure stability,excellent kinetic behaviors and ion-storage mechanism together enable the MVOH to demonstrate satisfactory specific capacity of 450 mA h g^(−1)at 0.2 A g^(−1),excellent rate performance of 288.8 mA h g^(−1)at 10 A g^(−1)and long cycle life over 20,000 cycles at 5 A g^(−1).This work provides a practical cathode material,and contributes to the understanding of the ion-intercalation mechanism and structural evolution of the vanadium-based cathode for AZIBs.

THERMODYNAMICS ADSORPTION OF MANGANESE ION ON 1-(2-PYRIDYLAZO)-2-NAPHTHOL-6-SULPHONIC ACID IMPREGNATED RESIN

An ion-exchange resin of type 201×7 was impregnated with the reagent 1-(2-Pyridylazo)-2-naphthol-6-sulphonic Acid (PAN-S). The adsorption characteristics of PAN-S resin for manganese ion were studied on the static equilibrium adsorption. Within temperature range of 288K^313K and the concentration range investigated, equilibrium data for the adsorption of manganese ions from aqueous solutions by PAN-S resin were obtained and correlated with Freundlich and Langmuir equation. The results showed that the process of the adsorption of manganese ions from aqueous solution by PAN-S was an exothermic process. Estimations of the isothermic enthalpy change of adsorption,free energy change and entropy of adsorption are reported,and the adsorption behaviors are reasonably interpreted.

Design of manganese ion coated Prussian blue nanocarrier for the therapy of refractory diffuse large B-cell lymphoma based on a comprehensive analysis of ferroptosis regulators from clinical cases

Diffuse large B-cell lymphoma(DLBCL)is a prevalent human malignancy,and understanding its biology will help identify problems in refractory patients and customize alternative therapies for them.We found that DLBCL can be stratified into two independent subtypes with different clinical characteristics and outcomes by consensus clustering of expression of ferroptosis regulatory genes,which proves that ferroptosis is effective in treating refractory cases.In this work,we constructed a novel ferroptosis nanocarrier(PBPMn@PEG)by coating Prussian blue nanoparticles with manganese ions and encapsulating them with poly(ethyleneglycol).The low efficiency of the Fenton reaction of Prussian blue nanoparticles can be improved greatly by manganese coating,and can effectively generate hydroxyl radicals,and induce ferroptosis of lymphoma cells(SU-DHL-10 cells)by down-regulating ferroptosis suppressor genes and up-regulating ferroptosis driver genes.It also induces effective cell apoptosis,which is synergistic with ferroptosis for DLBCL therapy.In vivo experiments also prove that PBPMn@PEG achieved a better anti-tumor effect by up-regulating COX2,HO-1/hemeoxygenase-1(HMOX1),and NADPH oxidase-4(NOX4),and downregulating FSP1 and GPX4,with lower biotoxicity.As a novel and potential DLBCL drug carrier,our discovery served as a foundation for the treatment of the refractory DLBCL by inducing ferroptosis for DLBCL treatment in addition to the therapeutic effect of drugs.

Effects of ferrous and manganese ions on anammox process in sequencing batch biofilm reactors

Ferrous and manganese ions, as essential elements, significantly affect the synthesis of Haem-C, which participates in the energy metabolism and proliferation of anammox bacteria. In this study, two identical sequencing batch biofilm reactors were used to investigate the effects of ferrous and manganese ions on nitrogen removal efficiency and the potential of metal ions serving as electron donor/acceptors in the anammox process. Fluorescence in situ hybridization analysis was applied to investigate the microbial growth. Results showed that the nitrogen removal increased at high concentrations of Fe2＋ and Mn2＋ and the maximum removal efficiency was nearly 95% at Fe2＋ 0.08 mmol/L and Mn2＋ 0.05 mmol/L, which is nearly 15% and 8% higher than at the lowest Fe2＋ and Mn2＋ concentrations （0.04 and 0.0125 mmol/L）. The stabilities of the anammox reactor and the anammox bacterial growth were also enhanced with the elevated Fe2＋ and Mn2＋ concentrations. The Fe2＋ and Mn2＋were consumed by anammox bacteria along with the removal of ammonia and nitrite. Stoichiometry analysis showed Fe2＋ could serve as an electron donor for NO3-N in the anammox process. Nitrate could be reduced with Fe2＋ serving as the electron donor in the anammox system, which causes the value of NO^-N/NH4-N to decrease with the increasing of N-removal efficiency.

Adsorptive removal of iron and manganese ions from aqueous solutions with microporous chitosan/polyethylene glycol blend membrane

Microporous chitosan （CS） membranes were directly prepared by extraction of poly（ethylene glycol） （PEG） from CS/PEG blend membrane and were examined for iron and manganese ions removal from aqueous solutions. The different variables affecting the adsorption capacity of the membranes such as contact time, pH of the sorption medium, and initial metal ion concentration in the feed solution were investigated on a batch adsorption basis. The affinity of CS/PEG blend membrane to adsorb Fe（II） ions is higher than that of Mn（II） ions, with adsorption equilibrium achieved after 60 min for Fe（II） and Mn（II） ions. By increasing CS]PEG ratio in the blend membrane the adsorption capacity of metal ions increased. Among all parameters, pH has the most significant effect on the adsorption capacity, particularly in the range of 2.9-5.9. The increase in CS/PEG ratio was found to enhance the adsorption capacity of the membranes. The effects of initial concentration of metal ions on the extent of metal ions removal were investigated in detail. The experimental data were better fitted to Freundlich equation than Langmuir. In addition, it was found that the iron and manganese ions adsorbed on the membranes can be effectively desorbed in 0.1 mol/L HCl solution （up to 98% desorption efficiency） and the blend membranes can be reused almost without loss of the adsorption capacity for iron and manganese ions.

Inhibiting manganese(Ⅱ)from catalyzing electrolyte decomposition in lithium-ion batteries

A once overlooked source of electrolyte degradation incurred by dissolved manganese(Ⅱ)species in lithium-ion batteries has been identified recently.In order to deactivate the catalytic activity of such manganese(II)ion,1-aza-12-crown-4-ether(A12C4)with cavity size well matched manganese(Ⅱ)ion is used in this work as electrolyte additive.Theoretical and experimental results show that stable complex forms between A12C4 and manganese(II)ions in the electrolyte,which does not affect the solvation of Li ions.The strong binding effect of A12C4 additive reduces the charge density of manganese(II)ion and inhibits its destruction of the PF_(6)^(-)structure in the electrolyte,leading to greatly improved thermal stability of manganese(II)ions-containing electrolyte.In addition to bulk electrolyte,A12C4 additive also shows capability in preventing Mn^(2+) from degrading SEI on graphite surface.Such bulk and interphasial stability introduced by A12C4 leads to significantly improved cycling performance of LIBs.

Transfer of manganese and ferro ions by manganese bacteria

The experimental results of the redox of manganese and ferro ions by manganese bacteria are described. Under the aerobic conditions, the manganese bacteria can oxidate Mn2+ into Mn4+. In the course of the manganese bacteria multiplication, the continual increaes of environmental pH is advantageous to the oxidation of manganese and the rise of environmental temperature helps the bacteria to speed the oxidation of manganese ions. The manganese bacteria can fastly oxidate Fe2+ in the culture containing low vaient ferro into Fe3+, its oxidation speed being faster than that of manganese oxide. Under the anaerobic conditions,the manganese bacteria can reduce high valent ferro in solutioninto low valent ferro and distinctly lower the environmental pH.

β-MnO_(2) with proton conversion mechanism in rechargeable zinc ion battery

Rechargeable aqueous zinc ion battery(RAZIB)is a promising energy storage system due to its high safety,and high capacity.Among them,manganese oxides with low cost and low toxicity have drawn much attention.However,the under-debate proton reaction mechanism and unsatisfactory electrochemical performance limit their applications.Nanorod b-MnO_(2) synthesized by hydrothermal method is used to investigate the reaction mechanism.As cathode materials for RAZIB,the Zn//b-MnO_(2) delivers 355 mA h g^(-1)(based on cathode mass)at0.1 A g^(-1),and retain 110 mA h g^(-1) after 1000 cycles at 0.2 A g^(-1).Different from conventional zinc ion insertion/extraction mechanism,the proton conversion and Mn ion dissolution/deposition mechanism of b-MnO_(2) is proposed by analyzing the evolution of phase,structure,morphology,and element of b-MnO_(2) electrode,the pH change of electrolyte and the determination of intermediate phase MnO OH.Zinc ion,as a kind of Lewis acid,also provides protons through the formation of ZHS in the proton reaction process.This study of reaction mechanism provides a new perspective for the development of Zn//MnO_(2) battery chemistry.

Biomimetic manganese-based theranostic nanoplatform for cancer multimodal imaging and twofold immunotherapy

The limited clinical response and serious side effect have been challenging in cancer immunotherapy resulting from immunosuppressive tumor microenvironment(TME)and inferior drug targeting.Herein,an active targeting TME nanoplatform capable of revising the immunosuppressive TME microenvironment is designed.Briefly,gold nanorods(GNRs)are covered with silica dioxide(SiO_(2))and then coated manganese dioxide(MnO_(2))to obtain GNRs@SiO_(2)@MnO_(2)(GSM).Myeloid-derived suppressor cells(MDSCs)membrane is further camouflaged on the surface of GSM to obtain GNRs@SiO_(2)@MnO_(2)@MDSCs(GSMM).In this system,GSMM inherits active targeting TME capacity of MDSCs.The localized surface plasmon resonance of GNRs is developed in near-infraredⅡwindow by MnO_(2)layer coating,realizing NIR-Ⅱwindow photothermal imaging and photoacoustic imaging of GSMM.Based on the release of Mn^(2+)in acidic TME,GSMM can be also used for magnetic resonance imaging.In cancer cells,Mn^(2+)catalyzes H_(2)O_(2)into·OH for(chemodynamic therapy)CDT leading to activate cGAS-STING,but also directly acts on STING inducing secretion of typeⅠinterferons,pro-inflammatory cytokines and chemokines.Additionally,photothermal therapy and CDT-mediated immunogenic cell death of tumor cells can further enhance anti-tumor immunity via exposure of CRT,HMGB1 and ATP.In summary,our nanoplatform realizes multimodal cancer imaging and dual immunotherapy.