Lithium-rich layered cathode material(LLM)can meet the requirement of power lithium-ion energy storage devices due to the great energy ***,the de/intercalation of Li+will cause the irreversible loss of lattice oxygen ...
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Lithium-rich layered cathode material(LLM)can meet the requirement of power lithium-ion energy storage devices due to the great energy ***,the de/intercalation of Li+will cause the irreversible loss of lattice oxygen and trigger transition metal(TM)ions migrate to Li+vacancies,resulting in capacity *** we brought Ti4+in substitution of TM ions in Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2),which could stabilize structure and expand the layer spacing of ***,optimized Ti-substitution can regulate the anions and cations of LLM,enhance the interaction with lattice oxygen,increase Ni^(3+) and Co^(3+),and improve Mn^(4+) coordination,improving reversibility of oxygen redox activation,maintaining the stable framework and facilitating the Li^(+) ***,we found 5%Ti-substitution sample delivered a high discharge capacity of 244.2 mAh/g at 50 mA/g,an improved cycling stability to 87.3%after 100 cycles and enhanced rate *** Ti-substitution gives a new pathway to achieve high reversible cycle retention for LLMs.
Ceramic hollow spheres have great potential for deep-sea ***,the irregularity of the conventional molding process,among other reasons,results in low wall thickness uniformity of hollow *** solve this problem,in this w...
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Ceramic hollow spheres have great potential for deep-sea ***,the irregularity of the conventional molding process,among other reasons,results in low wall thickness uniformity of hollow *** solve this problem,in this work,we developed a biaxial rotation grouting process for deep-sea ceramic hollow buoyancy spheres,which improves the drawbacks of the traditional rotary grouting method that results in poor wall thickness uniformity of the hollow spheres due to its irregular rotational *** this paper,an experimental study was carried out to investigate the effects of different rotational methods,rotational speeds,rotational time,solid phase content,*** the wall thickness uniformity of ceramic hollow *** results show that the hollow floating balls prepared by the biaxial rotation method have the lowest wall thickness standard deviation(0.04)when the rotation speed is 60 rpm,the molding time is 8 min,and the solid phase content is 70 wt%.After the hydrostatic pressure test of 120 MPa,the hydrostatic compressive strength of hollow spheres prepared by the biaxial rotation method was increased by 31.67%compared with that of the traditional process.
Co/NC catalysts modified with rare earth elements(La,Ce,Pr)were prepared by pyrolysis of rare earth elements doped *** experimental results show that the modification of rare earth elements significantly improves the ...
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Co/NC catalysts modified with rare earth elements(La,Ce,Pr)were prepared by pyrolysis of rare earth elements doped *** experimental results show that the modification of rare earth elements significantly improves the ammonia decomposition activity and stability of the Co/NC *** La-Co/NC catalyst can achieve an 82.3%ammonia decomposition and 18.4 mmol hydrogen production rate at 550℃with a GHSV of 20000 cm^(3)·h^(-1).Furthermore,no obvious performance degradation is observed after 72 hours of reaction for all rare earth elements modified *** is shown that the modification of rare earth elements significantly improves the surface alkalinity and surface chemical state of the catalyst,and thus improves the ammonia decomposition activity of the catalyst.A new type of high-performance ammonia decomposition Co-based catalyst is proposed,and the promoting effect of rare earth elements on the activity of ammonia decomposition is revealed.
Industrially prepared artificial graphite(AG)is attractive for potassium-ion batteries(PIBs),but its rate performance is poor and the production process is energy intensive,so developing an efficient strategy to produ...
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Industrially prepared artificial graphite(AG)is attractive for potassium-ion batteries(PIBs),but its rate performance is poor and the production process is energy intensive,so developing an efficient strategy to produce novel graphite with low energy consumption and high performance is economically ***,a nanostructured graphite composed of multi-walled carbon nanotubes(MWCNTs)and graphite shells was prepared by one-pot method through low-temperature pyrolysis of iron-based metal-organic framework(MOF)and carbon *** high graphitization degree of nanostructured graphite makes the initial Coulombic efficiency(ICE)exceed 80%,and the three-dimensional(3D)conductive network ensures a specific capacity of 234 mAh·g^(−1)after 1000 cycles at a high current density of 500 mA·g^(−1).In addition,the typical graphite potassium storage mechanism is also demonstrated by in situ X-ray diffraction(XRD)and in situ Raman spectroscopy,and its practicality is also proved by the voltage of the full *** work provides a feasible way to optimize the practical production process of AG and expand its application in energy storage.
Self-reconstruction of catalysts during oxygen evolution reaction(OER)is crucial for the development of energy conversion ***,the relationship between the specific atomic structure of pre-catalysts and their electroca...
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Self-reconstruction of catalysts during oxygen evolution reaction(OER)is crucial for the development of energy conversion ***,the relationship between the specific atomic structure of pre-catalysts and their electrocatalytic behavior after reconstruction via dual-ion leaching has not been extensively *** this work,we design a highly effective non-noble metal OER catalyst with heterointerface through continuous self-reconstruction of Co_(2)(OH)_(3)Cl@NiMoO_(4)as pre-catalyst by a straightforward dual-ion(***_(4)^(2-)and Cl^(-))***-situ Raman and in-situ Fourier transform infrared(FT-IR)spectroscopy have precisely identified the progressive phase transformation of the pre-catalyst during self-reconstruction,which results in a stable heterojunction of CoOOH and NiOOH(CoOOH@NiOOH).Further calculations based on density functional theory(DFT)of CoOOH@NiOOH evident that more electrons will be aggregated in the Fermi level of ***,Gibbs free energy(ΔG)for different OER steps of CoOOH@NiOOH exhibit lower energy costs of all intermediates,implying the well catalytic ***,the catalyst derived from dual-ion leaching displays outstanding OER performance,characterized by an overpotential of 275 mV at a current density of 10 mA·cm^(-2)and exceptional stability over 12 h *** work successfully paves a way of finding high-performance OER catalysts based on non-noble metal through dual-ion leaching during self-reconstruction.
Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and t...
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Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic ***,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP ***,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like *** results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride.
A machine learning(ML)-based random forest(RF)classification model algorithm was employed to investigate the main factors affecting the formation of the core-shell structure of BaTiO_(3)-based ceramics and their inter...
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A machine learning(ML)-based random forest(RF)classification model algorithm was employed to investigate the main factors affecting the formation of the core-shell structure of BaTiO_(3)-based ceramics and their interpretability was analyzed by using Shapley additive explanations(SHAP).An F1-score changed from 0.8795 to 0.9310,accuracy from 0.8450 to 0.9070,precision from 0.8714 to 0.9000,recall from 0.8929 to 0.9643,and ROC/AUC value of 0.97±0.03 was achieved by the RF classification with the optimal set of features containing only 5 features,demonstrating the high accuracy of our model and its high *** the interpretability analysis of the model,it was found that the electronegativity,melting point,and sintering temperature of the dopant contribute highly to the formation of the core-shell structure,and based on these characteristics,specific ranges were delineated and twelve elements were finally obtained that met all the requirements,namely Si,Sc,Mn,Fe,Co,Ni,Pd,Er,Tm,Lu,Pa,and *** the process of exploring the structure of the core-shell,the doping elements can be effectively localized to be selected by choosing the range of features.
In the scope of developing new electrochemical concepts to build batteries with high energy density,chloride ion batteries(CIBs)have emerged as a candidate for the next generation of novel electrochemical energy stora...
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In the scope of developing new electrochemical concepts to build batteries with high energy density,chloride ion batteries(CIBs)have emerged as a candidate for the next generation of novel electrochemical energy storage technologies,which show the potential in matching or even surpassing the current lithium metal batteries in terms of energy density,dendrite-free safety,and elimination of the dependence on the strained lithium and cobalt ***,the development of CIBs is still at the initial stage with unsatisfactory performance and several challenges have hindered them from reaching *** this review,we examine the current advances of CIBs by considering the electrode material design to the electrolyte,thus outlining the new opportunities of aqueous CIBs especially combined with desalination,chloride redox battery,*** respect to the developing road of lithium ion and fluoride ion batteries,the possibility of using solid-state chloride ion conductors to replace liquid electrolytes is tentatively *** beyond,perspectives and clear suggestions are concluded by highlighting the major obstacles and by prescribing specific research topics to inspire more efforts for CIBs in large-scale energy storage applications.
Due to its abundant sodium content and low cost,sodium-ion battery(SIB)has become an effective substitute and supplement for lithium-ion batteries,which has a broad development prospect in largescale energy storage **...
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Due to its abundant sodium content and low cost,sodium-ion battery(SIB)has become an effective substitute and supplement for lithium-ion batteries,which has a broad development prospect in largescale energy storage ***-super-ionic conductor(NASICON)structural materials have stable 3D skeleton structures and open Na+transport channels,which is a very promising SIB cathode *** in the typical NASICON material Na_(3)V_(2)(PO_(4))_(3)(NVP),the number of electrons involved in NVP per formula unit is less than 2 at the stable voltage window,which limits the further improvement of battery *** this work,we report another NASICON structured Na_(3)V_(4/3)Cr_(2/3)(PO_(4))_(3)@C(NVCP@C),which is obtained by Cr-doped NVP through spray *** taking full advantage of the voltage platforms of V^(5+/4+),V^(4+/3+),and V^(3+/2+)in the window of 1.5-4.4 V,NVCP@C delivered a high discharge capacity(175 mAh g^(-1))and durable cyclability(86%capacity retention for 2000 cycles).In-situ X-ray diffraction results demonstrate that the reversible structural evolution accompanies by solid-solution reaction and two-phase reaction mechanisms co-exist during charge/discharge *** coupled with Na^(+)preembedded hard carbon(HC),the assembled NVCP@C//HC full cell delivers a high capacity(105 mAh g^(-1))and long cycling performance(70%after 1000 cycles).This Cr-doped NVP method offers new insights into the design of high-energy NASICON-structured cathode materials.
To achieve high microwave permeability in wide-band for the micron-thick magnetic films,[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer structure was proposed by co-sputtering Fe and FeNi to form the magnetic layers and Cr to f...
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To achieve high microwave permeability in wide-band for the micron-thick magnetic films,[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer structure was proposed by co-sputtering Fe and FeNi to form the magnetic layers and Cr to form the *** multilayer structure contributes to the high permeability by reducing the coercivity and diminishing out-of-plane *** maximum imaginary permeability of[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer film reaches a large value of 800 at 0.52 GHz even though its overall thickness exceeds 1μ***,the magnetic resonance frequency of the multilayer film can be modulated from 0.52 to 1.35 GHz by adjusting the sputtering power of Fe from 0 to 86 W,and its bandwidth for μ’’>200(Δf) is as large as 2.0 *** desirable broad Δf of magnetic permeability,which can be well fitted by the Landau-Lifshitz-Gilbert equations,is due to dual magnetic resonances originated from double magnetic phases of Fe and FeNi that are of different saturation *** micron-thick multilayer films with high permeability in extended waveband are promising candidate for electromagnetic noise suppression application.
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