Doped phosphide is promising in earthabundant element based catalysts for hydrogen evolution reaction(HER). Here we employ ammonium hypophosphite(NH4H2PO2) to synthesize a novel parallel doped catalyst,nitrogen doped ...Doped phosphide is promising in earthabundant element based catalysts for hydrogen evolution reaction(HER). Here we employ ammonium hypophosphite(NH4H2PO2) to synthesize a novel parallel doped catalyst,nitrogen doped molybdenum phosphide nanoparticles(NPs)supported on nitrogen doped carbon nanotubes(N-MoP/N-CNTs). The NH4H2PO2 as a bifunctional agent severs as both phosphidation agent and nitrogen source, which makes the synthetic route simple and efficient. The as-obtained parallel doped N-MoP/N-CNTs show an overpotential of 103±5 mV at 10 mA cm-2, which is 140 mV lower than that of MoP NPs. The enhanced HER performance is attributed to the electronic effect by doped MoP and CNTs supports. This work provides a facile route to synthesize doped phosphides for the potential applications in hydrogen energy.展开更多
Bubble evolution behaviors play important roles in bubble emission reactions.Here we fabricated one-dimensional(1D)-aligned MoSx microgrids to investigate the influence of the periodic structure on bubble releasing.It...Bubble evolution behaviors play important roles in bubble emission reactions.Here we fabricated one-dimensional(1D)-aligned MoSx microgrids to investigate the influence of the periodic structure on bubble releasing.It is demonstrated that the utilization of the surface energy released during coalescence of bubbles causes them to jump from the electrode,which can be an effective route to eliminate the bubble shielding effect.Under the optimized architecture with 40-μm-wide grooves,the generated bubbles tend to coalesce and release from the electrode with much smaller size(65%less in volume).By balancing the coalescence efficiency and the adhesive work via the architecture engineering,the electrocatalytic performance can be promoted with the rapid bubble removal and lowered ohmic resistance.The results provide new insights into the rational design of novel catalytic electrode architectures and promote their applications in related fields.展开更多
It is a great challenge to prepare non-noble metal electrocatalysts toward hydrogen evolution reaction(HER)with large current density.Synergistic electronic and morphological structures of the catalyst have been consi...It is a great challenge to prepare non-noble metal electrocatalysts toward hydrogen evolution reaction(HER)with large current density.Synergistic electronic and morphological structures of the catalyst have been considered as an effective method to improve the catalytic performance,due to the enhanced intrinsic activity and enlarged accessible active sites.Herein,we present novel ternary Co_(1-x)V_(x)P nanoneedle arrays with modulated electronic and morphological structures as an electrocatalyst for highly efficient HER in alkaline solution.The NF@Co1-xVxP catalyst shows a remarkable catalytic ability with low overpotentials of 46 and 226 mV at current densities of 10 and 400 mA cm^(-2),respectively,as well as a small Tafel slope and superior stability.Combining the experimental and computational study,the excellent catalytic performance was attributed to the improved physical and chemical properties(conductivity and surface activity),large active surface area,and fast reaction kinetics.Furthermore,the assembled Co–V based electrolyzer(NF@Co_(1-x)V_(x)–HNNs(+)||NF@Co_(1-x)V_(x)P(-))delivers small full-cell voltages of 1.58,1.75,and 1.92 V at 10,100,and 300 mA cm^(-2),respectively.Our findings provide a systematic understanding on the V–incorporation strategy to promote highly efficient ternary electrocatalysts via synergistic control of morphology and electronic structures.展开更多
Topological nodal line（DNL） semimetals, a closed loop of the inverted bands in its bulk phases, result in the almost flat drumhead-like non-trivial surface states（DNSSs） with an unusually high electronic density n...Topological nodal line（DNL） semimetals, a closed loop of the inverted bands in its bulk phases, result in the almost flat drumhead-like non-trivial surface states（DNSSs） with an unusually high electronic density near the Fermi level. High catalytic active sites generally associated with high electronic densities around the Fermi level, high carrier mobility and a close-to-zero free energy of the adsorbed state of hydrogen（？G_（H＊）≈0） are prerequisite to design alternative of precious platinum for catalyzing electrochemical hydrogen production from water. By combining these two aspects, it is natural to consider if the DNLs are a good candidate for the hydrogen evolution reaction（HER） or not because its DNSSs provide a robust platform to activate chemical reactions. Here, through first-principles calculations we reported a new DNL TiSi-type family, exhibiting a closed Dirac nodal line due to the linear band crossings in k_y=0 plane.The hydrogen adsorbed state on the surface yields ？G_（H＊） to be almost zero and the topological charge carries participate in HER. The results highlight a new routine to design topological quantum catalyst utilizing the topological DNL-induced surface bands as active sites, rather than edge sites-, vacancy-,dopant-, strain-, or heterostructure-created active sites.展开更多
基金supported by the National Key Research and Development Program of China (2017YFA0206500)the National Natural Science Foundation of China (21671014)the Fundamental Research Funds for the Central Universities (buctrc201522)
文摘Doped phosphide is promising in earthabundant element based catalysts for hydrogen evolution reaction(HER). Here we employ ammonium hypophosphite(NH4H2PO2) to synthesize a novel parallel doped catalyst,nitrogen doped molybdenum phosphide nanoparticles(NPs)supported on nitrogen doped carbon nanotubes(N-MoP/N-CNTs). The NH4H2PO2 as a bifunctional agent severs as both phosphidation agent and nitrogen source, which makes the synthetic route simple and efficient. The as-obtained parallel doped N-MoP/N-CNTs show an overpotential of 103±5 mV at 10 mA cm-2, which is 140 mV lower than that of MoP NPs. The enhanced HER performance is attributed to the electronic effect by doped MoP and CNTs supports. This work provides a facile route to synthesize doped phosphides for the potential applications in hydrogen energy.
基金the National Natural Science Foundation of China(21675007,21676015,21520102002,91622116 and 22005022)the National Key Research and Development Project(2018YFB1502401 and 2018YFA0702002)+2 种基金the Royal Society and Newton Fund through Newton Advanced Fellowship award(NAF\R1\191294)the Program for Changjiang Scholars and Innovation Research Team in the University(IRT1205)the Fundamental Research Funds for the Central Universities and the long-term subsidy mechanism from the Ministry of Finance and the Ministry of Education of China。
文摘Bubble evolution behaviors play important roles in bubble emission reactions.Here we fabricated one-dimensional(1D)-aligned MoSx microgrids to investigate the influence of the periodic structure on bubble releasing.It is demonstrated that the utilization of the surface energy released during coalescence of bubbles causes them to jump from the electrode,which can be an effective route to eliminate the bubble shielding effect.Under the optimized architecture with 40-μm-wide grooves,the generated bubbles tend to coalesce and release from the electrode with much smaller size(65%less in volume).By balancing the coalescence efficiency and the adhesive work via the architecture engineering,the electrocatalytic performance can be promoted with the rapid bubble removal and lowered ohmic resistance.The results provide new insights into the rational design of novel catalytic electrode architectures and promote their applications in related fields.
基金the National Natural Science Foundation of China(21671096,21603094 and21905180)the Natural Science Foundation of Guangdong Province(2018B030322001 and 2018A030310225)+4 种基金Shenzhen Peacock Plan(KQTD2016022620054656)Shenzhen Key Laboratory Project(ZDSYS201603311013489)the Basic Research Project of the Science and Technology Innovation Commission of Shenzhen(JCYJ20190809115413414)the Science and Technology Development Fund from Macao SAR(FDCT–0102/2019/A2,FDCT–0035/2019/AGJ and FDCT–0154/2019/A3)the Multi-Year Research Grants(MYRG2017–00027–FST and MYRG2018–00003–IAPME)from the University of Macao。
文摘It is a great challenge to prepare non-noble metal electrocatalysts toward hydrogen evolution reaction(HER)with large current density.Synergistic electronic and morphological structures of the catalyst have been considered as an effective method to improve the catalytic performance,due to the enhanced intrinsic activity and enlarged accessible active sites.Herein,we present novel ternary Co_(1-x)V_(x)P nanoneedle arrays with modulated electronic and morphological structures as an electrocatalyst for highly efficient HER in alkaline solution.The NF@Co1-xVxP catalyst shows a remarkable catalytic ability with low overpotentials of 46 and 226 mV at current densities of 10 and 400 mA cm^(-2),respectively,as well as a small Tafel slope and superior stability.Combining the experimental and computational study,the excellent catalytic performance was attributed to the improved physical and chemical properties(conductivity and surface activity),large active surface area,and fast reaction kinetics.Furthermore,the assembled Co–V based electrolyzer(NF@Co_(1-x)V_(x)–HNNs(+)||NF@Co_(1-x)V_(x)P(-))delivers small full-cell voltages of 1.58,1.75,and 1.92 V at 10,100,and 300 mA cm^(-2),respectively.Our findings provide a systematic understanding on the V–incorporation strategy to promote highly efficient ternary electrocatalysts via synergistic control of morphology and electronic structures.
基金supported by the National Science Fund for Distinguished Young Scholars (51725103)the National Natural Science Foundation of China (51671193 and 51474202)+1 种基金the Science Challenging Project (TZ2016004)All calculations have been performed on the high-performance computational cluster in Shenyang National University Science and Technology Park and the National Supercomputing Center in Guangzhou (TH-2 system) with special program for applied research of the NSFC-Guangdong Joint Fund (the second phase) (U1501501)
文摘Topological nodal line（DNL） semimetals, a closed loop of the inverted bands in its bulk phases, result in the almost flat drumhead-like non-trivial surface states（DNSSs） with an unusually high electronic density near the Fermi level. High catalytic active sites generally associated with high electronic densities around the Fermi level, high carrier mobility and a close-to-zero free energy of the adsorbed state of hydrogen（？G_（H＊）≈0） are prerequisite to design alternative of precious platinum for catalyzing electrochemical hydrogen production from water. By combining these two aspects, it is natural to consider if the DNLs are a good candidate for the hydrogen evolution reaction（HER） or not because its DNSSs provide a robust platform to activate chemical reactions. Here, through first-principles calculations we reported a new DNL TiSi-type family, exhibiting a closed Dirac nodal line due to the linear band crossings in k_y=0 plane.The hydrogen adsorbed state on the surface yields ？G_（H＊） to be almost zero and the topological charge carries participate in HER. The results highlight a new routine to design topological quantum catalyst utilizing the topological DNL-induced surface bands as active sites, rather than edge sites-, vacancy-,dopant-, strain-, or heterostructure-created active sites.
