Classical molecular dynamics(MD)simulations ae performed to investigate the effects of mechanical strain on the thermal conductivity of single-layer black phosphorus(SLBP)nanoribbons along different directions at room...Classical molecular dynamics(MD)simulations ae performed to investigate the effects of mechanical strain on the thermal conductivity of single-layer black phosphorus(SLBP)nanoribbons along different directions at room temperature.The results show that the tensile strain afects the thermal conductivity of nanoribbons by changing thephonon density of state(DOS)and mean free path(M FP).The thermal conductivity shows a sharp enhancement with the tensile strain applied along the armchai diection,while it increases slowly with the strain applied along the zigzag diection.This phenomenon cm be mainly explained by effects of the phonon DOS and MFP.The increasing strain along the armchai direction weakens DOS and strengthens MFP clearly.However,when it comes to the increasing strain along the zigzag deection'DOS enliances significantly while MFP decreases slightly.The findings explore the relationship between the tensile strain and the thermal conductivity reasonably and can provide a reliable method to estimate the MFP of black phosphorus.展开更多
This work provides an effective low-cost synthesis and in-depth mechanistic study of high quality large-area nitrogen-doped graphene(NG) films. These films were synthesized using urea as nitrogen source and methane as...This work provides an effective low-cost synthesis and in-depth mechanistic study of high quality large-area nitrogen-doped graphene(NG) films. These films were synthesized using urea as nitrogen source and methane as carbon source, and were characterized by scanning electron microscopy(SEM), Raman spectroscopy and X-ray photoelectron spectroscopy(XPS). The N doping level was determined to be 3.72 at.%, and N atoms were suggested to mainly incorporated in a pyrrolic N configuration. All distinct Raman peaks display a shift due to the nitrogen-doping and compressive strain. The increase in urea concentration broadens the D and 2D peak's Full Width at Half Maximum(FWHM), due to the decrease of mean free path of phonons. The N-doped graphene exhibited an n-type doping behavior with a considerably high carrier mobility of about 74.1 cm2/(V s), confirmed by electrical transport measurements.展开更多
基金The National Natural Science Foundation of China(No.51575104)
文摘Classical molecular dynamics(MD)simulations ae performed to investigate the effects of mechanical strain on the thermal conductivity of single-layer black phosphorus(SLBP)nanoribbons along different directions at room temperature.The results show that the tensile strain afects the thermal conductivity of nanoribbons by changing thephonon density of state(DOS)and mean free path(M FP).The thermal conductivity shows a sharp enhancement with the tensile strain applied along the armchai diection,while it increases slowly with the strain applied along the zigzag diection.This phenomenon cm be mainly explained by effects of the phonon DOS and MFP.The increasing strain along the armchai direction weakens DOS and strengthens MFP clearly.However,when it comes to the increasing strain along the zigzag deection'DOS enliances significantly while MFP decreases slightly.The findings explore the relationship between the tensile strain and the thermal conductivity reasonably and can provide a reliable method to estimate the MFP of black phosphorus.
基金supported by the National Natural Science Foundation of China(Grant Nos.91123009,10975115)the Natural Science Foundation of Fujian Province of China(Grant No.2012J06002)
文摘This work provides an effective low-cost synthesis and in-depth mechanistic study of high quality large-area nitrogen-doped graphene(NG) films. These films were synthesized using urea as nitrogen source and methane as carbon source, and were characterized by scanning electron microscopy(SEM), Raman spectroscopy and X-ray photoelectron spectroscopy(XPS). The N doping level was determined to be 3.72 at.%, and N atoms were suggested to mainly incorporated in a pyrrolic N configuration. All distinct Raman peaks display a shift due to the nitrogen-doping and compressive strain. The increase in urea concentration broadens the D and 2D peak's Full Width at Half Maximum(FWHM), due to the decrease of mean free path of phonons. The N-doped graphene exhibited an n-type doping behavior with a considerably high carrier mobility of about 74.1 cm2/(V s), confirmed by electrical transport measurements.
