Understanding and preventing degradation in organic photovoltaics

Placeholder Show Content

Abstract/Contents

Abstract
Organic photovoltaics (OPVs) are an emerging photovoltaic technology with the potential for low-cost, high-throughput processing. The record laboratory efficiency for these solar cells are now at 9.2% which is approximately half of the efficiency of a traditional rooftop solar module; however, the stability of OPV needs to also reach a lifetime comparable to a 25-year traditional rooftop solar module to be competitive. Here I present the three major modes of degradation in OPV power conversion efficiency for solar cells tested at one-sun illumination in a controlled atmosphere. The first mode is a photo-induced burn-in that occurs in the first few hundred hours of operation and decreases efficiency by ~25%. This burn-in can be avoided by creating a highly aggregated blend of the polymer electron donor material and fullerene electron acceptor material. The second mode is thermal degradation that occurs above the Tg of the material. In the first portion of thermal degradation, the polymer donor material adheres to the top electrode and degrades performance by blocking the transport of electrons. This degradation can be mitigated by making the top electrode the electron withdrawing electrode. The last mode of degradation is long-term degradation and appears to be related to the amount of oxygen that the OPV device is exposed to. The three modes of degradation are shown to be general for several OPV material sets. Lastly, the talk will present rules for highly stable OPV devices and by following these rules we can produce OPVs with a lifetime in excess of 15 years and OPVs with less than half of the typical burn-in.

Description

Type of resource text
Form electronic; electronic resource; remote
Extent 1 online resource.
Publication date 2014
Issuance monographic
Language English

Creators/Contributors

Associated with Sachs-Quintana, Isaac Tobias
Associated with Stanford University, Department of Materials Science and Engineering.
Primary advisor McGehee, Michael
Thesis advisor McGehee, Michael
Thesis advisor Heilshorn, Sarah
Thesis advisor Salleo, Alberto
Advisor Heilshorn, Sarah
Advisor Salleo, Alberto

Subjects

Genre Theses

Bibliographic information

Statement of responsibility Isaac Tobias Sachs-Quintana.
Note Submitted to the Department of Materials Science and Engineering.
Thesis Thesis (Ph.D.)--Stanford University, 2014.
Location electronic resource

Access conditions

Copyright
© 2014 by Isaac Tobias Sachs-Quintana
License
This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).

Also listed in

Loading usage metrics...