%0 Journal Article
%A Kim, Seong Min
%A Ha, J. W.
%A Kwon, J.-H.
%A Jung, J.-H.
%A Bae, J.-H.
%A Kim, H.
%A Kim, J. B.
%D 2015
%I Begell House
%K *p - n* interface effects, piezoelectric core-shell nanowires, FEM simulation
%N 2
%P 115-121
%R 10.1615/IntJMultCompEng.2015011405
%T NUMERICAL STUDY OF *p − n* INTERFACE EFFECTS
%U http://dl.begellhouse.com/journals/61fd1b191cf7e96f,7132a71b3cf0c1d3,4e9fc151359b20f4.html
%V 13
%X In this study, we simulated piezoelectric enhancements of *p − n* core-shel nanowires with an inner-core cylinder of *n*-type ZnO and an outer-shell cylinder of *p*-type poly-3-hexylthiophene. Compared with conventional *n*-type ZnO nanowires, the piezoelectric potential of *p − n* core-shell nanowires with the same dimensions (core part; *n*-ZnO), calculated by subtracting the electrical potential of the uncompressed core-shell nanowires [*φ*_{ele} (*T*_{z} = 0)] from that of compressed nanowires (*φ*^{total}_{ele}) according to *φ*^{p − n}_{piezo} = *φ*^{total}
_{ele} − *φ*_{ele} (*T*_{z} = 0), are enhanced by more than a factor of 10. As the magnitude of vertical external compression (*T*_{z}) is varied from 0 to −9×10^{7} N/m^{2}, the piezoelectric potential of the model system increases. This improvement in the piezoelectric potential is attributed to the presence of a depletion zone at the *p − n* interface (space-charge region), which reduces the carrier screening of the piezoelectric potential by removing free carriers. Our results suggest that the structure proposed here for *p − n* core-shell nanowires
could improve the performance of photovoltaic systems.
%8 2015-03-06