Recent progress in degradation and stabilization of organic solar cells

Enhanced lifetime of organic photovoltaic diodes utilizing a ternary blend including an insulating polymer

“…However, the lifetime of OPVs is a key factor hindering commercialization [4,5]. Although the lifetime of poly(3-hexylthiophene) (P3HT) : phenyl-C61-butyric acid methyl ester (PCBM) devices can be up to 1000 hours [6], this still represents significantly worse performance than, for example, inorganic silicon photovoltaics, which have a lifetime approaching 25 years [7].…”

“…Chemical degradation may result from light [9], temperature [10], oxygen and water [11,12], with water and oxygen being considered the principal factors [4,12]. These molecular species can cause oxidation of the OPV materials [13] and electrodes [14], in turn leading to electronic traps [15] and low performance.…”

“…The use of insulating polymers as a third component in OPV blends has been suggested as a strategy to improve their lifetime [4]. This approach, whereby the 'active' organic semiconductor is blended with an inert insulating polymer, has been used in organic field effect transistors (OFETs), where it has been shown to increase lifetime with minimal effect on electronic properties [18,19].…”

“…Atomic force microscopy (AFM) and conductive AFM measurements suggest that the PMMA forms columnar features dotted within an otherwise largely P3HT:PCBM matrix. It is proposed that the PMMA absorbs ambient 4 water vapor, and in doing so, reduces the rate of trap formation in the active OPV materials.…”

Printable luminescent down shifter for enhancing efficiency and stability of organic photovoltaics

“…Recent research in this area has led to the report of a power conversion efficiency (PCE) of over 10% [1]. However, there are still challenges that the technologists developing OPVs need to overcome before it can become a mainstream solar technology, in particular combining high efficiency and long term operational stability in outdoor environments [2]. The causes of instability are numerous and complex and are induced or accelerated by a range of environmental effects such as temperature, water and ultraviolet (UV) light exposure [3], with the latter leading to photooxidation of active layer components or polymer chain scission [4,5].…”