Enhancing P3HT/TiO 2 hybrid photovoltaic performance by incorporating high surface potential silica nanodots into hole transport layer
Journal
Journal of Physical Chemistry C
Journal Volume
116
Journal Issue
2
Pages
1955-1960
Date Issued
2012
Author(s)
Abstract
We offer a novel approach to improve the performance of P3HT/TiO 2 hybrid photovoltaic devices by incorporating either hydroxyl- or amino-functionalized silica nanodots (SND-OH or SND-NH 2) into the hole transport layer of the PEDOT:PSS. The SNDs serve as screens between conducting polymer and ionomer PSS to improve the phase separation and charge transport of the PEDOT:PSS hole transport layer. The power conversion efficiency (PCE) was thus improved by 1.45 and 2.61 fold for devices fabricated with PEDOT:PSS containing 1 wt % of SND-OH (SND-OH device) and 1 wt % of SND-NH 2 (SND-NH 2 device), respectively, when compared with the devices fabricated by neat PEDOT:PSS. The increase in PCE arises from an increase in short circuit currents, which are affected by the phase separation of PEDOT:PSS with possessing incorporated SNDs. The low surface potential of hydroxyl-functionalized SNDs (SND-OH) is easily aggregated in the PEDOT:PSS solution and forms large-sized phase separation in the PEDOT:PSS film. The aggregation of SND-OH causes slight decreases in the resistance of PEDOT:PSS thin film from (61 ± 1 to 69 ± 4)× 10 6 Ohm/square and a decrease in the shielding effects of the SNDs. In contrast, the high surface potential of amino-functionalized SNDs are dispersed uniformly in the PEDOT:PSS solution and form morphologies with small-sized domains in the PEDOT:PSS film. As a result, the sheet resistance of PEDOT:PSS thin films is decreased from (61 ± 1 to 46 ± 3) × 10 6 Ohm/square. Therefore, the SND-NH 2 device exhibits greater performance over the SND-OH devices. © 2011 American Chemical Society.
SDGs
Other Subjects
Hole transport layers; Nanodots; PEDOT:PSS; Photovoltaic devices; Photovoltaic performance; Power conversion efficiencies; Shielding effect; Conversion efficiency; Equipment; Hole mobility; Phase separation; Photovoltaic effects; Silica; Surface potential; Thin films; Conducting polymers
Type
journal article