The controllab.e construction of non-noble metal based bifunctional catalysts with high activities towards oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of great significance,but remains a ***,we ...
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The controllab.e construction of non-noble metal based bifunctional catalysts with high activities towards oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of great significance,but remains a ***,we reported an effective method to synthesize cobalt-nitrogen doped mesoporous carbon-based bifunctional oxygen electrocatalyst with controllab.e phosphorus content(Co-N-P_(X)-MC,X=0.5,1.0,1.5,2.0).The mesoporous carbon substrate endowed the asprepared samples with more exposed active surface(236.50 m^(2)·g^(−1))and the most appropriate doping ratio of phosphorus had been investigated to be 1.5(Co-N-P1.5-MC).For ORR,Co-N-P1.5-MC exhibited excellent catalytic activity with more positive onset potential(1.01 V)and half-wave potential(0.84 V)than the other *** OER,Co-N-P1.5-MC also showed a low overpotential of 415 *** experimental results and density-functional theory(DFT)calculations,the outstanding bifunctional catalytic performance of Co-N-P1.5-MC was due to the synergistic cooperation between the P and N dopants,which could reduce the reaction barriers and was favorable for ORR and ***,the Zn-air battery using Co-N-P1.5-MC as the cathode showed remarkable battery performance with high stability(could operate stably for over 160 h at 10 mA·cm^(−2))and maximum power density(119 mW·cm^(−2)),demonstrating its potential for practical *** work could provide significant enlightenment towards the design and construction of bifunctional oxygen electrocatalyst for next-generation electrochemical devices.
Erratum to Nano Research,2024,17(4):2704-2711 https://***/10.1007/s12274-023-6115-y(1)In the article,the table of contents(TOC)image was unfortunately mispresented.
Erratum to Nano Research,2024,17(4):2704-2711 https://***/10.1007/s12274-023-6115-y(1)In the article,the table of contents(TOC)image was unfortunately mispresented.
Li_(7)La_(3)Zr_(2)O_(12)(LLZO)is considered as a promising solid-state electrolyte due to its high ionic conductivity,wide electrochemical window,and excellent electrochemical ***,its application in solid-state lithiu...
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Li_(7)La_(3)Zr_(2)O_(12)(LLZO)is considered as a promising solid-state electrolyte due to its high ionic conductivity,wide electrochemical window,and excellent electrochemical ***,its application in solid-state lithium metal batteries(SSLMBs)is impeded by the growth of lithium dendrites in LLZO due to some reasons such as its high electronic *** this study,lithium fluoride(LiF)was introduced into Ta-doped LLZO(LLZTO)to modify its grain boundaries to enhance the performance of SSLMBs.A nanoscale LiF layer was uniformly coated on the LLZTO grains,creating a threedimensional continuous electron-blocking network at the grain *** from the electronic insulator LiF and the special structure of the modified LLZTO,the symmetric cells based on LLZO achieved a high critical current density(CCD)of 1.1 mA·cm^(-2)(in capacity-constant mode)and maintained stability over 2000 h at 0.3 mA·cm^(-2).Moreover,the full cells combined with a LiFePO_(4)(LFP)cathode,demonstrated excellent cycling performance,retaining 97.1% of capacity retention after 500 cycles at 0.5 ***,this work provides a facile and effective approach for preparing a modified electrolyte suitable for high-performance SSLMBs.
Catalyst with high performance has drawn increasing attention recently due to its significant advantages in chemical reactions such as speeding up the reaction,lowering the reaction temperature or pressure,and proceed...
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Catalyst with high performance has drawn increasing attention recently due to its significant advantages in chemical reactions such as speeding up the reaction,lowering the reaction temperature or pressure,and proceeding without itself being *** the superior catalytic performance of precious metal catalysts,transition metal oxides offer a promising route for substitution of precious metals in catalysis arising from their low cost,intrinsic activity and sufficient ***-type oxide SmMn_(2)O_(5) exhibits a unique crystal structure containing double crystalline fields,and nowadays is used widely as the catalyst in different chemical reactions,including the reactions of vehicle emissions reduction and oxygen evolution reaction,gas sensors,and metal-air batteries,promoting attention in catalytic perfor-mance *** our knowledge,there is no review article covering the comprehensive informa-tion of SmMn2 O 5 and its *** we review the recent progress in understanding of the crys-tal structure of SmMn_(2)O_(5) and its basic physical *** then summarize the catalytic sources of SmMn_(2)O_(5) and reaction mechanisms,while the strategies to improve catalytic performance of SmMn_(2)O_(5) are further ***,we provide a perspective on how to make further progress in catalytic applications.
In this work,we synthesized a brand-new Al foam with a periodic structure via a simple powder metallurgical *** periodic architecture consists of both hierarchical porous and bi-directional composition-graded *** resu...
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In this work,we synthesized a brand-new Al foam with a periodic structure via a simple powder metallurgical *** periodic architecture consists of both hierarchical porous and bi-directional composition-graded *** results show that the hierarchical porous material includes large pores on millimeter scale inheriting from the hollow structure of the Al tubes,and small pores on mi-crometer scale produced by the sintering of Al/Mg *** bi-directional Mg concentration-graded structure is formed in the tube walls due to the condensation of Mg vapor in the inner tube *** addition of Mg powders achieves excellent metallurgical bonding between the Al powders and the hollow tubes at 550℃.The plateau stress and energy absorption capacity of the Al foam in y-axis compression are significantly higher than that in the x-axis due to their anisotropic *** general,the Al foam with Mg addition presents the most superior compression performance,and we believe that our find-ings could open up a unique strategy for developing high-performance metallic foams with the periodic architecture involving both hierarchical porous and bi-directional graded structure.
Based on simplified calculations of one-dimensional wave systems,loading pressure platform curves of Al-Cu gradient materials(GMs)impactor were *** Al-Cu GMs were prepared using tape-pressing sintering,and their acous...
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Based on simplified calculations of one-dimensional wave systems,loading pressure platform curves of Al-Cu gradient materials(GMs)impactor were *** Al-Cu GMs were prepared using tape-pressing sintering,and their acoustic properties were characterized to match the design *** parallelism of the Al-Cu GM was confirmed using a three-dimensional surface profilometry machine.A one-stage light-gas gun was used to launch the Al-Cu GM,impacting an Al-LiF target at a velocity of 400 m/*** results of the experimental strain rate demonstrate that the Al-Cu GMs can realize the precise control of the strain rate within the range of 10^(4)‒10^(5)/s in the high-speed impact experiments.
Wide-bandgap(WBG)perovskite solar cells(PSCs)play a fundamental role in perovskite-based tandem solar ***,the efficiency of WBG PSCs is limited by significant open-circuit voltage losses,which are primarily caused by ...
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Wide-bandgap(WBG)perovskite solar cells(PSCs)play a fundamental role in perovskite-based tandem solar ***,the efficiency of WBG PSCs is limited by significant open-circuit voltage losses,which are primarily caused by surface *** this study,we present a novel method for modifying surfaces using the multifunctional S-ethylisothiourea hydrobromide(SEBr),which can passivate both Pb^(-1)and FA^(-1)terminated surfaces,Moreover,the SEBr upshifted the Fermi level at the perovskite interface,thereby promoting carrier *** proposed method was effective for both 1.67 and 1.77 eV WBG PSCs,achieving power conversion efficiencies(PCEs)of 22.47%and 19.90%,respectively,with V_(OC)values of 1.28 and 1.33 V,along with improved film and device *** this advancement,we were able to fabricate monolithic all-perovskite tandem solar cells with a champion PCE of 27.10%,This research offers valuable insights for passivating the surface trap states of WBG perovskite through rational multifunctional molecular engineering.
Compositions and morphologies of Pt-based electrocatalysts have great impact on the electrocatalytic activity and stability of oxygen reduction reaction(ORR).Herein,we report a novel design of one-dimensional(1D)Pt-Pd...
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Compositions and morphologies of Pt-based electrocatalysts have great impact on the electrocatalytic activity and stability of oxygen reduction reaction(ORR).Herein,we report a novel design of one-dimensional(1D)Pt-Pd dendritic nanotubular heterostructures(DTHs)by controlling the degree of Pt 2+-Pt reduction reaction and Pd-Pt galvanic replacement reaction with uniform Pd nanowires as sacrificial *** obtained Pt-Pd bimetallic DTHs catalyst exhibited uniform and dense Pt dendritic nanobranches on the surface of 1D hollow Pt-Pd alloy nanotubes,possessing superior catalytic activity for ORR compared to state-of-the-art commercial Pt/C ***,the Pt_(4)Pd DTHs catalyst showed efficient mass activity(MA,1.05 A mg_(Pt)^(−1))and specific activity(SA,1.25 mA cm_(Pt)^(−2))at 0.9 V(***),and the catalyst exhibited high stability with 90.4%MA retention after 20000 potential *** Pt-Pd bimetallic DTHs configuration combines the advantages of 1D hollow nanostructures and dense Pt dendritic nanobranches,which results in rich electrochemical active surface sites,fast charge transport,and multiple dendritic anchoring points contact on carbon support,thus boosting its catalytic activity and stability towards electrocatalysis.
The thermal diffusivity and specific heat capacity of continuous casting (SC) and high-pressure diecasting (HPDC) aluminum alloys before and after T4 and T6 heat treatments were measured at room temperature, and their...
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Flexible piezoelectric materials capable of withstanding large deformation play key roles in flexible electronics. Ferroelectric ceramics with a high piezoelectric coefficient are inherently brittle, whereas polar pol...
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Flexible piezoelectric materials capable of withstanding large deformation play key roles in flexible electronics. Ferroelectric ceramics with a high piezoelectric coefficient are inherently brittle, whereas polar polymers exhibit a low piezoelectric coefficient. Here we report a highly stretchable/compressible piezoelectric composite composed of ferroelectric ceramic skeleton, elastomer matrix and relaxor ferroelectric-based hybrid at the ceramic/matrix interface as dielectric transition layers, exhibiting a giant piezoelectric coefficient of 250 picometers per volt, high electromechanical coupling factor keff of 65%,ultralow acoustic impedance of 3MRyl and high cyclic stability under 50% compression strain. The superior flexibility and piezoelectric properties are attributed to the electric polarization and mechanical load transfer paths formed by the ceramic skeleton, and dielectric mismatch mitigation between ceramic fillers and elastomer matrix by the dielectric transition layer. The synergistic fusion of ultrahigh piezoelectric properties and superior flexibility in these polymer composites is expected to drive emerging applications in flexible smart electronics.
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