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Supporting Information
Variable Electronic Properties of Lateral Phosphorene-
Graphene Heterostructures
Xiaoqing Tian, Lin Liu, Yu Du,* Juan Gu, Jian-bin Xu,* and Boris I. Yakobson*
1. Electronic properties of the heterostructures of 15-APNR/16-AGNR
(a) (b)
Figure S1. (a) Band structure and (b) DOS of the heterostructure of 15-APNR/16-AGNR
The relaxed heterostructure of 15-APNR/16-AGNR has a width of 4.5 nm. 15-APNR and 16-
AGNR are connected by robust chemical bonds. The length of P-C bond is 1.86Å at this interface,
which is the same to that of 15-APNR/15-AGNR. Heterostructure of 15-APNR/16-AGNR has a
band gap of 0.66 eV as shown in Figure S1(a). Its corresponding density of states (DOS) is shown
in Figure S1(b). Based on the DOS, the VBM and CBM are mainly contributed from the 15-
APNR and 16-AGNR respectively. This is confirmed by the charge distribution of HOMO and
LUMO orbitals ( see Figure S3g, h). The mh* and me
* are 0.28 and 0.37 times m0 calculated by Eq
(1). The mh* is smaller than me
*. According to the Drude model, the mobility of hole carriers will
be 1.32 times that of electron carriers. The charge transfer is the same as that of heterostructure of
15-APNR/15-AGNR. The calculated Φw is 4.47 eV which is comparable to pristine monolayer
graphene’s theoretical value of 4.48 eV and experimental value 4.6 eV. The Φws of 2-APNR/2-
AGNR, 4-APNR/4-AGNR, 7-APNR/7-AGNR, 16-APNR/15-AGNR and 16-APNR/16-AGNR
are 4.80, 4.84, 4.50, 4.42 and 4.45 eV, respectively. The corresponding band gaps are 1.53, 1.55,
0.93, 0.63 and 0.65 eV, respectively. Thus the work function can be modulated by the width and
constituents of the heterostructures. The larger the band gap the larger the work function.