The poor stability of non-noble metal catalysts in oxygen reduction reaction(ORR) is a main bottleneck that limits their big-scale application in metal-air batteries. Herein, we construct a chainmail catalyst(Co-NC-AD...The poor stability of non-noble metal catalysts in oxygen reduction reaction(ORR) is a main bottleneck that limits their big-scale application in metal-air batteries. Herein, we construct a chainmail catalyst(Co-NC-AD) with outstanding stability, via the competitive complexation and post absorption strategy,consisting of highly graphitic layers wrapped uniform-size Co nanoparticles(Co-NPs). Experiments combined with density functional theory(DFT) calculations jointly confirmed that the electron transfer occurred from the inner Co-NPs to the external graphitic layers. It facilitated the adsorption process of oxygen molecules and the hybridization of the O-2 p and C-1 p orbitals, which accelerated the ORR reaction kinetics. Consequently, our prepared Co-NC-AD shows excellent ORR activity, offered with a more positive initial potential(E_(onset)= 0.95 V) and half-wave potential(E_(1/2)= 0.86 V). The remarkable stability and resistance of methanol poisoning are merited from the protection effect of stable graphitic layers. In addition, the high electrochemical performance of Co-NC-AD-based zinc-air battery demonstrates their potential for practical applications. Therefore, our work provides new ideas for the design of nanoconfined catalysts with high stability and activity.展开更多
Graphdiyne(GDY)is fascinating in the construction of efficient and stable catalysts,but their performance is still somewhat restricted due to GDY’s thicker layers,as well as hydrophobic and relatively chemically iner...Graphdiyne(GDY)is fascinating in the construction of efficient and stable catalysts,but their performance is still somewhat restricted due to GDY’s thicker layers,as well as hydrophobic and relatively chemically inert surfaces.Herein,via oxidationexfoliation-reduction strategy,the self-supported electrode material of CoP nanosheets with ultrathin oxygen-containing GDY wrapping(CoP@RGDYO)for effective HER is constructed.The wrapping of ultrathin oxygen-containing GDY promotes charge transfer,improves the surface property,and enhances the acid and alkali resistance as well as the structural stability of the catalyst.As a result,CoP@RGDYO shows enhanced activity and stability in both acidic and alkaline media.Especially,it exhibits a low overpotential of 86 mV and exceptional stability under a 14000-cycle cyclic voltammetry scanning in alkaline media.This work provides new ideas for the design of GDY hybrid materials and the preparation of high-efficiency catalysts.展开更多
Decoupled electrolysis of water is a promising strategy for peak load regulation of electricity.The key to developing this technology is to construct decoupled devices containing stable redox mediators and correspondi...Decoupled electrolysis of water is a promising strategy for peak load regulation of electricity.The key to developing this technology is to construct decoupled devices containing stable redox mediators and corresponding efficient catalysts,which remains a considerable challenge.Herein,we designed a high-performance device,using polysulfides as mediators and graphene-encapsulated CoNi as catalysts.It produced H2 with a low potential of 0.82 V at 100 mA/cm^(2),saving 60.2%more energy than direct water electrolysis.The capacity of H2 production reached 2.53105 mAh/cm^(2),which is the highest capacity reported so far.This device exhibited excellent cyclability in 15-day recycle tests,without any decay of performance.The calculation results revealed that the electronic structure of the graphene shell was modulated by the electron transfer from N-dopant and metal core,which significantly facilitated recycle of polysulfides on graphene surfaces.This study provides a promising method for constructing a smart grid by developing efficient decoupled devices.展开更多
基金supported by the National Natural Science Foundation of China(51872115,51932003)the 2020 International Cooperation Project of the Department of Science and Technology of Jilin Province(20200801001GH)+1 种基金the Project supported by State Key Laboratory of Luminescence and Applications(KLA-2020-05)the Project for Self-innovation Capability Construction of Jilin Province Development and Reform Commission(2021C026)。
文摘The poor stability of non-noble metal catalysts in oxygen reduction reaction(ORR) is a main bottleneck that limits their big-scale application in metal-air batteries. Herein, we construct a chainmail catalyst(Co-NC-AD) with outstanding stability, via the competitive complexation and post absorption strategy,consisting of highly graphitic layers wrapped uniform-size Co nanoparticles(Co-NPs). Experiments combined with density functional theory(DFT) calculations jointly confirmed that the electron transfer occurred from the inner Co-NPs to the external graphitic layers. It facilitated the adsorption process of oxygen molecules and the hybridization of the O-2 p and C-1 p orbitals, which accelerated the ORR reaction kinetics. Consequently, our prepared Co-NC-AD shows excellent ORR activity, offered with a more positive initial potential(E_(onset)= 0.95 V) and half-wave potential(E_(1/2)= 0.86 V). The remarkable stability and resistance of methanol poisoning are merited from the protection effect of stable graphitic layers. In addition, the high electrochemical performance of Co-NC-AD-based zinc-air battery demonstrates their potential for practical applications. Therefore, our work provides new ideas for the design of nanoconfined catalysts with high stability and activity.
基金supported by the National Natural Science Foundation of China(Nos.201972123,U2003307,and 21861037)the National Key Research and Development Program of China(No.2021YFB35006042)+2 种基金the Natural Science Foundation of Xinjiang Uygur Autonomous Region of China(Nos.2021D01C097,2020D01C062,and 2021D01D09)Scientific Research Program of the Higher Education Institution of Xinjiang(XJEDU2021Y005)Open Project of PCOSS(Xiamen University)(2021X20).
文摘Graphdiyne(GDY)is fascinating in the construction of efficient and stable catalysts,but their performance is still somewhat restricted due to GDY’s thicker layers,as well as hydrophobic and relatively chemically inert surfaces.Herein,via oxidationexfoliation-reduction strategy,the self-supported electrode material of CoP nanosheets with ultrathin oxygen-containing GDY wrapping(CoP@RGDYO)for effective HER is constructed.The wrapping of ultrathin oxygen-containing GDY promotes charge transfer,improves the surface property,and enhances the acid and alkali resistance as well as the structural stability of the catalyst.As a result,CoP@RGDYO shows enhanced activity and stability in both acidic and alkaline media.Especially,it exhibits a low overpotential of 86 mV and exceptional stability under a 14000-cycle cyclic voltammetry scanning in alkaline media.This work provides new ideas for the design of GDY hybrid materials and the preparation of high-efficiency catalysts.
基金We gratefully acknowledge the financial support from the Ministry of Science and Technology of the People’s Republic of China(no.2016YFA0204100 and 2016YFA0200200)the National Natural Science Foundation of China(no.21890753 and 21988101)+3 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(no.QYZDB-SSW-JSC020)the DNL Cooperation Fund,CAS(no.DNL180201)the Natural Science Foundation of Shandong Province(ZR2019MEE015)the Key Research and Development Plan of Shandong Province(2018GSF117042).
文摘Decoupled electrolysis of water is a promising strategy for peak load regulation of electricity.The key to developing this technology is to construct decoupled devices containing stable redox mediators and corresponding efficient catalysts,which remains a considerable challenge.Herein,we designed a high-performance device,using polysulfides as mediators and graphene-encapsulated CoNi as catalysts.It produced H2 with a low potential of 0.82 V at 100 mA/cm^(2),saving 60.2%more energy than direct water electrolysis.The capacity of H2 production reached 2.53105 mAh/cm^(2),which is the highest capacity reported so far.This device exhibited excellent cyclability in 15-day recycle tests,without any decay of performance.The calculation results revealed that the electronic structure of the graphene shell was modulated by the electron transfer from N-dopant and metal core,which significantly facilitated recycle of polysulfides on graphene surfaces.This study provides a promising method for constructing a smart grid by developing efficient decoupled devices.
