O.E. Glukhova – Dr.Sc.(Phys.-Math.), Professor, Head of Department of Radiotechnique and Electrodynamics,  Saratov State University named after N.G. Chernyshevsky

E-mail: GlukhovaOE@info.sgu.ru

D.S. Shmygin – Assistant, 

Department of Radiotechnique and Electrodynamics, Saratov State University named after N.G. Chernyshevsky E-mail: shmygin.dmitriy@gmail.com

M.M. Slepchenkov – Ph.D.(Phys.-Math.), Associate Professor, 

Department of Radiotechnique and Electrodynamics, Saratov State University named after N.G. Chernyshevsky E-mail: slepchenkovm@mail.ru

Pillared graphene is a carbon composite that consists of graphene sheets and bonded chemically single-walled carbon nanotubes (SWCNTs), oriented vertically. During the computational experiment, the electron density functional method was used in the tightbinding approximation with self-consistent charge calculation, the band structure and the work function were calculated in the process of numerical solution of the stationary Schrödinger equation for extended periodic structures of pillared graphene. To determine the equilibrium configurations, a reactive empirical bond-order method was additionally used. Pillared graphene monolayer, bilayer and 3D-structures of pillared graphene were considered. By monolayer structures are meant with one layer of single-walled carbon nanotubes and two graphene sheets, bilayer structures have two layers of single-walled carbon nanotubes and three graphene sheets. The sizes of the supercells were: 2.46 nm and 2.13 nm along the X and Y axes accordingly for pillared graphene monolayer, 4.92 nm and 4.26 nm for bilayer and 3D-pillared graphene. On the Z axis, the first two types of structures were non-periodic, and for the third, the translation vector length in this direction varied from 1.6 nm to 4.06 nm. During the study, it was found that the work function for all topological configurations of pillared graphene at all considered lengths of single-walled carbon nanotubes in the composite decreases, and for two-layer and 3D-pillared graphene, the work function decreases at the same potassium mass fractions in the system back proportional to the length of the tubes – the work function decreases more significantly for short SWCNTs. For all the structures considering, a decrease in the work function of 1 eV or more was observed at 10% and 2…2.5 eV at the maximum mass fraction of the investigated ones.

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