In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterpart...In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterparts.The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications.In this context,the atomic substitution method has emerged as a favorable approach.It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting materials.In this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC materials.The effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are discussed.The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these advancements.Finally,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized.展开更多
Single atom(SA)catalysts have achieved great success on highly selective heterogeneous catalysis due to their abundant and homogeneous active sites.The electronic structures of these active sites,restrained by their l...Single atom(SA)catalysts have achieved great success on highly selective heterogeneous catalysis due to their abundant and homogeneous active sites.The electronic structures of these active sites,restrained by their localized coordination environments,significantly determine their catalytic performances,which are difficult to manipulate.Here,we investigated the effect of localized surface plasmon resonance(LSPR)on engineering the electronic structures of single atomic sites.Typically,core–shell structures consisted of Au core and transition metal SAs loaded N-doped carbon(CN)shell were constructed,namely Au@M-SA/CN(M=Ni,Fe,and Co).It was demonstrated that plasmon-induced hot electrons originated from Au were directionally injected to the M-SAs under visible light irradiation,which significantly changed their electronic structures and meanwhile facilitated improved overall charge separation efficiency.The as-prepared Au@Ni-SA/CN exhibited highly efficient and selective photocatalytic CO_(2) reduction to CO performance,which is 20.8,17.5,and 6.9 times those of Au nanoparticles,Au@CN,and Ni-SA/CN,respectively.Complementary spectroscopy analysis and theoretical calculations confirmed that the plasmon enhanced Ni-SA/CN sites featured increased charge density for efficient intermediate activation,contributing to the superb photocatalytic performance.The work provides a new insight on plasmon and atomic site engineering for efficient and selective catalysis.展开更多
The semiconductor-based photoanodes have shown great potential on photoelectrochemical(PEC)hydrogen generation.Compared to the pristine semiconductor,photoanodes fabricated with doped semiconductors exhibit modulated ...The semiconductor-based photoanodes have shown great potential on photoelectrochemical(PEC)hydrogen generation.Compared to the pristine semiconductor,photoanodes fabricated with doped semiconductors exhibit modulated bandgap structure and enhanced charge separation efficiency,demonstrating improved optoelectronic properties.In this work,we develop a colloidal cation exchange(CE)strategy on versatile synthesis of heterovalent doped chalcogenide semiconductor thin films with high surface roughness.Using Ag-doped CdSe(CdSe:Ag)thin films as an example,the organized centimeter-scale CdSe:Ag films with nanometer-scale thickness(thickness around 80 nm,length×width around 1.5 cm×1.2 cm)exhibit enhanced optical absorbance ability and charge carrier density by tuning the energy levels of conduction and valence bands as well as improved electrical conductivity by Ag dopants compared to the pristine CdSe film obtained by the vapor-phase vacuum deposition strategy.In the meantime,the surface roughness of the as-prepared semiconductor thin films is also increased with abundantly exposed active sites to facilitate accessibility to water for hydrogen generation and suppress photogenerated carrier recombination.The CdSe:Ag film photoanodes exhibit superb PEC hydrogen generation performance with a photocurrent density of 0.56 mA/cm^(2) at 1.23 V versus reversible hydrogen electrode,which is nearly 3 times higher than the pristine CdSe film.This work provides a new strategy on colloidal synthesis of photoelectrodes with modulated heterovalent doping and surface roughness for PEC applications.展开更多
基金supported by the Teli Fellowship from Beijing Institute of Technology,the National Natural Science Foundation of China(Nos.52303366,22173109).
文摘In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterparts.The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications.In this context,the atomic substitution method has emerged as a favorable approach.It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting materials.In this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC materials.The effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are discussed.The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these advancements.Finally,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized.
基金supported by the National Natural Science Foundation of China(Nos.22375020,52272186,and 22105116)Beijing Institute of Technology Research Fund Program for Young Scholars.
文摘Single atom(SA)catalysts have achieved great success on highly selective heterogeneous catalysis due to their abundant and homogeneous active sites.The electronic structures of these active sites,restrained by their localized coordination environments,significantly determine their catalytic performances,which are difficult to manipulate.Here,we investigated the effect of localized surface plasmon resonance(LSPR)on engineering the electronic structures of single atomic sites.Typically,core–shell structures consisted of Au core and transition metal SAs loaded N-doped carbon(CN)shell were constructed,namely Au@M-SA/CN(M=Ni,Fe,and Co).It was demonstrated that plasmon-induced hot electrons originated from Au were directionally injected to the M-SAs under visible light irradiation,which significantly changed their electronic structures and meanwhile facilitated improved overall charge separation efficiency.The as-prepared Au@Ni-SA/CN exhibited highly efficient and selective photocatalytic CO_(2) reduction to CO performance,which is 20.8,17.5,and 6.9 times those of Au nanoparticles,Au@CN,and Ni-SA/CN,respectively.Complementary spectroscopy analysis and theoretical calculations confirmed that the plasmon enhanced Ni-SA/CN sites featured increased charge density for efficient intermediate activation,contributing to the superb photocatalytic performance.The work provides a new insight on plasmon and atomic site engineering for efficient and selective catalysis.
基金National Natural Science Foundation of China(grant nos.52272186 and 22105116)Beijing Institute of Technology Research Fund Program for Young Scholars.
文摘The semiconductor-based photoanodes have shown great potential on photoelectrochemical(PEC)hydrogen generation.Compared to the pristine semiconductor,photoanodes fabricated with doped semiconductors exhibit modulated bandgap structure and enhanced charge separation efficiency,demonstrating improved optoelectronic properties.In this work,we develop a colloidal cation exchange(CE)strategy on versatile synthesis of heterovalent doped chalcogenide semiconductor thin films with high surface roughness.Using Ag-doped CdSe(CdSe:Ag)thin films as an example,the organized centimeter-scale CdSe:Ag films with nanometer-scale thickness(thickness around 80 nm,length×width around 1.5 cm×1.2 cm)exhibit enhanced optical absorbance ability and charge carrier density by tuning the energy levels of conduction and valence bands as well as improved electrical conductivity by Ag dopants compared to the pristine CdSe film obtained by the vapor-phase vacuum deposition strategy.In the meantime,the surface roughness of the as-prepared semiconductor thin films is also increased with abundantly exposed active sites to facilitate accessibility to water for hydrogen generation and suppress photogenerated carrier recombination.The CdSe:Ag film photoanodes exhibit superb PEC hydrogen generation performance with a photocurrent density of 0.56 mA/cm^(2) at 1.23 V versus reversible hydrogen electrode,which is nearly 3 times higher than the pristine CdSe film.This work provides a new strategy on colloidal synthesis of photoelectrodes with modulated heterovalent doping and surface roughness for PEC applications.
