Piezoelectric transduction technology enables the direct conversion between mechanical and electrical energy,finding extensive applications in sensing,acoustics,imaging,actuation,and energy harvesting[1].Previous stud...Piezoelectric transduction technology enables the direct conversion between mechanical and electrical energy,finding extensive applications in sensing,acoustics,imaging,actuation,and energy harvesting[1].Previous studies on piezoelectric materials have primarily focused on ceramics or single-crystal materials characterized by wide band gaps(E_(g)>2.0 e V[2])and low electrical conductivity.In contrast,narrow-bandgap(E_(g)<0.5 eV[3])semiconductor materials typically exhibit high electrical conductivity,which is unfavorable for the effective accumulation of charges required to establish a stable voltage response.Consequently,experimental investigations into the piezoelectric effect of narrow-bandgap semiconductors are scarce.展开更多
Metal-organic frameworks(MOFs),which comprise metal cations and organic ligands connected through coordination bonds,exhibit exceptional porosity and tunable properties,making them promising for thermoelectric applica...Metal-organic frameworks(MOFs),which comprise metal cations and organic ligands connected through coordination bonds,exhibit exceptional porosity and tunable properties,making them promising for thermoelectric applications.However,most MOFs have low electrical conductivity,which limits their application in thermoelectric devices.Doping transition metal ions into MOF systems can provide adequate conductivity for thermoelectric conversion.Thus,in this study,the thermoelectric properties of Cu-doped nickel benzene-1,3,5-tricarboxylate(NiBTC)were investigated to optimize its carrier concentration and mobility.NiBTC was synthesized into a hollow structure to enhance its phonon scattering and then doped with copper to tune its electrical conductivity and Seebeck coefficient.The synthesis was confirmed through various characterization techniques,including XRD,FTIR spectroscopy,and electron microscopy.Cu doping significantly increased its electrical conductivity by~10%while slightly decreasing its Seebeck coefficient;however,high doping levels(15%)resulted in a CuBTC byproduct,which negatively affected its performance.The findings revealed that the substitution of Ni^(2+)with Cu^(2+)enhances its electrical performance by improving its carrier concentration and mobility,while the hollow structure reduces its thermal conductivity.The optimized Cu-NiBTC composite exhibited promising thermoelectric performance,with a maximum figure of merit of 0.571 at 473 K.This study highlights the potential of MOF-based composites for thermoelectric applications,promoting future advancements in energy-harvesting technologies.展开更多
文摘Piezoelectric transduction technology enables the direct conversion between mechanical and electrical energy,finding extensive applications in sensing,acoustics,imaging,actuation,and energy harvesting[1].Previous studies on piezoelectric materials have primarily focused on ceramics or single-crystal materials characterized by wide band gaps(E_(g)>2.0 e V[2])and low electrical conductivity.In contrast,narrow-bandgap(E_(g)<0.5 eV[3])semiconductor materials typically exhibit high electrical conductivity,which is unfavorable for the effective accumulation of charges required to establish a stable voltage response.Consequently,experimental investigations into the piezoelectric effect of narrow-bandgap semiconductors are scarce.
基金funded and conducted under the Competency Development Program for Industry Specialists of the Korean Ministry of Trade,Industry and Energy(MOTIE),operated by Korea Institute for Advancement of Technology(KIAT),(No.P0012453,Next-generation Display Expert Training Project for Innovation Process)supported by Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea government(MOTIE)(No.RS 2024-00398346,ESS BigData-Based O&M and Asset Management Technical Manpower Training).
文摘Metal-organic frameworks(MOFs),which comprise metal cations and organic ligands connected through coordination bonds,exhibit exceptional porosity and tunable properties,making them promising for thermoelectric applications.However,most MOFs have low electrical conductivity,which limits their application in thermoelectric devices.Doping transition metal ions into MOF systems can provide adequate conductivity for thermoelectric conversion.Thus,in this study,the thermoelectric properties of Cu-doped nickel benzene-1,3,5-tricarboxylate(NiBTC)were investigated to optimize its carrier concentration and mobility.NiBTC was synthesized into a hollow structure to enhance its phonon scattering and then doped with copper to tune its electrical conductivity and Seebeck coefficient.The synthesis was confirmed through various characterization techniques,including XRD,FTIR spectroscopy,and electron microscopy.Cu doping significantly increased its electrical conductivity by~10%while slightly decreasing its Seebeck coefficient;however,high doping levels(15%)resulted in a CuBTC byproduct,which negatively affected its performance.The findings revealed that the substitution of Ni^(2+)with Cu^(2+)enhances its electrical performance by improving its carrier concentration and mobility,while the hollow structure reduces its thermal conductivity.The optimized Cu-NiBTC composite exhibited promising thermoelectric performance,with a maximum figure of merit of 0.571 at 473 K.This study highlights the potential of MOF-based composites for thermoelectric applications,promoting future advancements in energy-harvesting technologies.
