1 research outputs found
Surfactant-Enriched ZnO Surface via Sol–Gel Process for the Efficient Inverted Polymer Solar Cell
In this study, we
demonstrate that the top surface is enriched
by surfactants, tetraoctylammonium bromide, and cetylpyridinium bromide
(CPB), in the sol–gel ZnO, being evidenced by the Br depth
profile of electron spectroscopy for chemical analysis data. X-ray
photoelectron spectroscopy results showed the formation of Zn–Br
bonding due to the oxygen defects occupied by Br at the surfactant-enriched
ZnO surface. The surfactant-enriched ZnO surface possessed a smoother
surface and more hydrophobicity than the pristine ZnO from the experimental
results of atomic force microscopy and contact angle, respectively.
On the basis of ultraviolet photoelectron spectroscopy data, the work
function slightly reduced due to the dipole built-up by the electrostatic
force between Br<sup>–</sup> and N<sup>+</sup> to enhance the
electron extraction ability. The improved properties benefited the
power conversion efficiency (PCE) of bulk-heterojunction polymer solar
cells (PSCs) by spin-coating the active layer on the surfactant-enriched
ZnO surface. The inverted PSCs with the surfactant-enriched ZnO surface
showed the highest PCE of 9.55% for the CPB case, in comparison with
the pristine ZnO surface (8.08% PCE). This study discloses that turning
the ZnO surface is easily achieved by the addition of surfactants
with different molecular structures in the sol–gel ZnO for
high performance polymer solar cells