Two-dimensional(2D)materials and their corresponding van der Waals(vd W)heterostructures are considered as promising candidates for highly efficient solar cell applications.A series of 2D HfX2(X=Cl,Br,I)monolayers are...Two-dimensional(2D)materials and their corresponding van der Waals(vd W)heterostructures are considered as promising candidates for highly efficient solar cell applications.A series of 2D HfX2(X=Cl,Br,I)monolayers are proposed,via first-principle calculations.The vibrational phonon spectra and molecular dynamics simulation results indicate that HfX2 monolayers possess dynamical and thermodynamical stability.Moreover,their electronic structure shows that their Heyd–Scuseria–Ernzerhof(HSE06)-based band values(1.033–1.475 eV)are suitable as donor systems for excitonic solar cells(XSCs).The material’s significant visible-light absorbing capability(~105 cm-1)and superior power conversion efficiency(~20%)are demonstrated by establishing a reasonable typeⅠvd W heterostructure.This suggests the significant potential of HfX2 monolayers as a candidate material for XSCs.展开更多
基金the National Key Research and Development Program of China(Grant No.2017YFB0405302)。
文摘Two-dimensional(2D)materials and their corresponding van der Waals(vd W)heterostructures are considered as promising candidates for highly efficient solar cell applications.A series of 2D HfX2(X=Cl,Br,I)monolayers are proposed,via first-principle calculations.The vibrational phonon spectra and molecular dynamics simulation results indicate that HfX2 monolayers possess dynamical and thermodynamical stability.Moreover,their electronic structure shows that their Heyd–Scuseria–Ernzerhof(HSE06)-based band values(1.033–1.475 eV)are suitable as donor systems for excitonic solar cells(XSCs).The material’s significant visible-light absorbing capability(~105 cm-1)and superior power conversion efficiency(~20%)are demonstrated by establishing a reasonable typeⅠvd W heterostructure.This suggests the significant potential of HfX2 monolayers as a candidate material for XSCs.
