The nitrogen reduction reaction(NRR)under ambient conditions is still challenging due to the inertness of N2.Herein,we report a series of superior NRR catalysts identified by examining Ti2NO2 MXenes embedded with 28 d...The nitrogen reduction reaction(NRR)under ambient conditions is still challenging due to the inertness of N2.Herein,we report a series of superior NRR catalysts identified by examining Ti2NO2 MXenes embedded with 28 different single-atom catalysts using first-principles calculations.The stability of this system was first verified using formation energies,and it is discovered that N2 can be effectively adsorbed due to the synergistic effect between single atom catalysis and the Ti atoms.Examination of the electronic structure demonstrated that this design satisfies orbital symmetry matching where“acceptor-donor”interaction scenario can be realized.A new“enzymatic-distal”reaction mechanism that is a mixture of the enzymatic and distal pathways was also discovered.Among all of the candidates,Ni anchored on MXene system achieves an onset potential as low as–0.13 V,which to the best of our knowledge is the lowest onset potential value reported to date.This work elucidates the significance of orbital symmetry matching and provides theoretical guidance for future studies.展开更多
Since the multicomponent signal with nonlinear time-frequency structures occupies a wide frequency band, and the spectral contents may alias, it is therefore difficult to separate the signal components and to separate...Since the multicomponent signal with nonlinear time-frequency structures occupies a wide frequency band, and the spectral contents may alias, it is therefore difficult to separate the signal components and to separate the signal from Ijackground noise. In this paper, a new signal separation method using FMmlet transform is proposed by taking the advantage that the atoms of FMm let transform can match both the linear and nonlinear time-varying structures. Theoretical predictions and numerical experiments show the feasibility of the methodology advocated.展开更多
文摘The nitrogen reduction reaction(NRR)under ambient conditions is still challenging due to the inertness of N2.Herein,we report a series of superior NRR catalysts identified by examining Ti2NO2 MXenes embedded with 28 different single-atom catalysts using first-principles calculations.The stability of this system was first verified using formation energies,and it is discovered that N2 can be effectively adsorbed due to the synergistic effect between single atom catalysis and the Ti atoms.Examination of the electronic structure demonstrated that this design satisfies orbital symmetry matching where“acceptor-donor”interaction scenario can be realized.A new“enzymatic-distal”reaction mechanism that is a mixture of the enzymatic and distal pathways was also discovered.Among all of the candidates,Ni anchored on MXene system achieves an onset potential as low as–0.13 V,which to the best of our knowledge is the lowest onset potential value reported to date.This work elucidates the significance of orbital symmetry matching and provides theoretical guidance for future studies.
基金Supported in part by the National Natural Science Foundation of China under Grant No.60172026
文摘Since the multicomponent signal with nonlinear time-frequency structures occupies a wide frequency band, and the spectral contents may alias, it is therefore difficult to separate the signal components and to separate the signal from Ijackground noise. In this paper, a new signal separation method using FMmlet transform is proposed by taking the advantage that the atoms of FMm let transform can match both the linear and nonlinear time-varying structures. Theoretical predictions and numerical experiments show the feasibility of the methodology advocated.
