As an excellent clean medium for hydrogen storage and fuel cell applications,the photolysis of ammonia via localized surface plasmon could be invoked as a promising route towards significantly reducing the temperature...As an excellent clean medium for hydrogen storage and fuel cell applications,the photolysis of ammonia via localized surface plasmon could be invoked as a promising route towards significantly reducing the temperature for conventional thermolysis.Here,we explore the underlying microscopic mechanism of ultrafast carrier dynamics in plasmon-mediated NH3 photodecomposition at the single-molecular level using real-time time-dependent density functional theory.The NH_(3)molecule adsorbed on the tip of archetypal magic metal clusters represented by tetrahedral Ag_(2)0 and icosahedral Ag147,splits within a hundred femtoseconds upon laser pulse illumination.We found that the splitting of the first N-H bond is dominated by the intramolecular charge transfer driven by localized surface plasmon.Surprisingly,the phase of laser pulse could modulate the dynamics of charge transfer and thus affect the plasmon-induced bond breaking.These findings offer a new avenue for NH3 decomposition and provide in-depth insights in designing highly efficient plasmon-mediated photocatalysts.展开更多
Understanding the microscopic mechanism of photoinduced sp^(2)-to-sp^(3) structural transformation in graphite is a scientific challenge with great importance.Here,the ultrafast dynamics and characteristics of laser-i...Understanding the microscopic mechanism of photoinduced sp^(2)-to-sp^(3) structural transformation in graphite is a scientific challenge with great importance.Here,the ultrafast dynamics and characteristics of laser-induced structural transformation in graphite are revealed by non-adiabatic quantum dynamic simulations.Under laser irradiation,graphite undergoes an interlayer compression and sliding stage,followed by a key period of intralayer buckling and interlayer bonding to form an intermediate sp^(2)-sp^(3) hybrid structure,before completing the full transformation to hexagonal diamond.The process is driven by the cooperation of charge carrier multiplication and selective phonon excitations through electron-phonon interactions,in which photoexcited hot electrons scattered into unoccupied high-energy conduction bands play a key role in the introduction of in-plane instability in graphite.This work identifies a photoinduced non-adiabatic transition pathway from graphite to diamond and shows far-reaching implications for designing optically controlled structural phase transition in materials.展开更多
基金We acknowledge financial support from MOST,the National Key Research and Development Project(No.2021YFA1400200)the National Natural Science Foundation of China(NSFC)(Nos.12025407,11774396,91850120,11934003,and 11674289)CAS(XDB330301).
文摘As an excellent clean medium for hydrogen storage and fuel cell applications,the photolysis of ammonia via localized surface plasmon could be invoked as a promising route towards significantly reducing the temperature for conventional thermolysis.Here,we explore the underlying microscopic mechanism of ultrafast carrier dynamics in plasmon-mediated NH3 photodecomposition at the single-molecular level using real-time time-dependent density functional theory.The NH_(3)molecule adsorbed on the tip of archetypal magic metal clusters represented by tetrahedral Ag_(2)0 and icosahedral Ag147,splits within a hundred femtoseconds upon laser pulse illumination.We found that the splitting of the first N-H bond is dominated by the intramolecular charge transfer driven by localized surface plasmon.Surprisingly,the phase of laser pulse could modulate the dynamics of charge transfer and thus affect the plasmon-induced bond breaking.These findings offer a new avenue for NH3 decomposition and provide in-depth insights in designing highly efficient plasmon-mediated photocatalysts.
基金We acknowledge partial financial support from the National Key Research and Development Program of China(No.2021YFA1400503,2021YFA1400201)National Natural Science Foundation of China(No.12025407,11774396 and 11934003,11974400)+1 种基金“Strategic Priority Research Program(B)”of Chinese Academy of Sciences(Grant No.XDB330301)M.G.acknowledges support from the China Postdoctoral Science Foundation(Grant No.2021M693369).
文摘Understanding the microscopic mechanism of photoinduced sp^(2)-to-sp^(3) structural transformation in graphite is a scientific challenge with great importance.Here,the ultrafast dynamics and characteristics of laser-induced structural transformation in graphite are revealed by non-adiabatic quantum dynamic simulations.Under laser irradiation,graphite undergoes an interlayer compression and sliding stage,followed by a key period of intralayer buckling and interlayer bonding to form an intermediate sp^(2)-sp^(3) hybrid structure,before completing the full transformation to hexagonal diamond.The process is driven by the cooperation of charge carrier multiplication and selective phonon excitations through electron-phonon interactions,in which photoexcited hot electrons scattered into unoccupied high-energy conduction bands play a key role in the introduction of in-plane instability in graphite.This work identifies a photoinduced non-adiabatic transition pathway from graphite to diamond and shows far-reaching implications for designing optically controlled structural phase transition in materials.
