Please use this identifier to cite or link to this item:
Title: Elucidating the impact of molecular packing and device architecture on the performance of nanostructured perylene diimide solar cells
Authors: Aluicio-Sarduy, Eduardo 
Singh, Ranbir R. 
Kan, Zhipeng 
Ye, Tengling 
Baidak, Aliaksandr 
Calloni, Alberto 
Berti, Giulia 
Duò, Lamberto 
Iosifidis, Agathaggelos 
Beaupré, Serge 
Leclerc, Mario 
Butt, Hans Jürgen 
Floudas, George A. 
Keivanidis, Panagiotis E. 
Keywords: Charge extraction;Non-fullerene acceptors;Organic photovoltaics;Perylene diimide;Vertical phase separation
Category: Nano-Technology
Field: Engineering and Technology
Issue Date: 29-Apr-2015
Publisher: American Chemical Society
Source: ACS Applied Materials and Interfaces, Volume 7, Issue 16, Pages 8687-8698
metadata.dc.doi: 10.1021/acsami.5b00827
Abstract: The performance of organic photovoltaic devices (OPV) with nanostructured polymer:perylene diimide (PDI) photoactive layers approaches the levels of the corresponding polymer:fullerene systems. Nevertheless, a coherent understanding of the difficulty for PDI-based OPV devices to deliver high power conversion efficiencies remains elusive. Here we perform a comparative study of a set of four different polymer:PDI OPV model systems. The different device performances observed are attributed to differences in the nanostructural motif of these composites, as determined by wide-angle X-ray scattering (WAXS) measurements. Long-range structural order in the PDI domain dictates (i) the stabilization energy and (ii) the concentration of the PDI excimers in the composites. The quenching of the PDI excimer photoluminescence (PL) is found to be insensitive to the former, but it depends on the latter. High PL quenching occurs for the low concentration of PDI excimers that are formed in PDI columns with a length comparable to the PDI excimer diffusion length. The stabilization of the PDI excimer state increases as the long-range order in the PDI domains improves. The structural order of the PDI domains primarily affects charge transport. Electron mobility reduces as the size of the PDI domain increases, suggesting that well-ordered PDI domains suffer from poor electronic connectivity. WAXS further reveals the presence of additional intermolecular PDI interactions, other than the direct face-to-face intermolecular coupling, that introduce a substantial energetic disorder in the polymer:PDI composites. Conventional device architectures with hole-collecting ITO/PEDOT:PSS bottom electrodes are compared with inverted device architectures bearing bottom electron-collecting electrodes of ITO/ZnO. In all cases the ZnO-functionalized devices surpass the performance of the conventional device analogues. X-ray photoelectron spectroscopy explains that in PEDOT:PSS-functionalized devices, the PDI component preferentially segregates closer to the hydrophilic PEDOT:PSS electrode, thus impeding the efficient charge extraction and limiting device photocurrent.
ISSN: 19448244
Rights: © 2015 American Chemical Society.
Type: Article
Appears in Collections:Άρθρα/Articles

Show full item record

Page view(s)

Last Week
Last month
checked on Dec 15, 2018

Google ScholarTM


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.