Environmental Engineering Reference
In-Depth Information
Figure 5.6
PDOS spectra along the longitude direction for Si atoms at
the surface layer (top panel) and inner layer (bottom panel) of the naked
SiNW (blue dash line) and H-SiNW (red solid line), respectively. The cross-
sectional areas of naked SiNW and H-SiNW are 2.36 nm
2
. Reprinted with
permission from [43].Copyright c
2012, City University of Hong Kong.
5.4 Surface Nitrogenation Effect on the Thermal
Conductivity of SiNWs
Figure 5.7 shows the longitudinal thermal conductivity of ni-
trogenated SiNWs as a function of surface nitrogenation ratio
at 300 K. The nitrogenated SiNWs show remarkably smaller
thermal conductivities compared to the fully hydrogenated SiNWs.
Nitrogenation of 14% of the surface Si atoms induces the reduction
of the thermal conductivity by
∼
43%, whereas 29% and 43%
surface nitrogenation further lower the thermal conductivity by
∼
60% and
∼
75%, respectively. The 50% surface nitrogenation has
negligible additional effect on the thermal conductivity compared
with the case of 43% surface nitrogenation. This nitrogenation-
induced attenuation in thermal conductivity has been experimen-
tally confirmed in nitrogenated nanocrystalline diamond (NCD)
