Enhanced Structural Stability and Performance Durability of Bulk Heterojunction Photovoltaic Devices Incorporating Metallic Nanoparticles

Abstract

Despite the progress on organic photovoltaic (OPV) performance, the photoactive layer degradation during prolonged solar illumination is still a major obstacle. In this work, an approach to mitigate the degradation pathway related to structural/morphological changes of the photoactive layer occurring upon continuous illumination in air is presented. It is shown, for the first time, that the incorporation of Ag nanoparticles in poly(3‐hexylthiophene) (P3HT) and [6‐6]‐phenyl‐C61‐butyric acid methyl ester bulk heterojunction (BHJ) leads to improved structural and morphological properties of the composite BHJ solar cells and to better photovoltaic (PV) stability after long periods of continuous illumination. This is evidenced by an original approach based on joint in‐situ time‐resolved X‐ray and atomic force microscopy monitoring. Besides the structural stability improvement and reduced photodegradation rate, it is shown that the composite blends exhibit superior PV performance compared to the pristine BHJs. It can be postulated that the incorporation of metallic nanoparticles in the BHJ leads to a dual enhancement, a plasmon absorption mediated effect, causing improved initial cell efficiency, and a structural stability effect giving rise to reduced degradation rate upon prolonged illumination. The results are in favor of the exploitation of polymer–nanoparticle composites as a promising approach to mitigate the aging effects in OPVs.

Uncovering loss mechanisms in silver nanoparticle-blended plasmonic organic solar cells

“…Nonetheless, all these issues may be resolvable through a prudent choice of the constituents and careful optimization of the device. From the analysis of our experimental results and careful comparison with the literature reports [8][9][10][11][12][13] , we can identify several key factors/ considerations for the design of hybrid plasmonic OSCs.…”

“…For instance, metallic nanoparticles (NPs) have been commonly employed as subwavelength antennas and scattering centres to enhance the absorption of BHJ films 3 . Typically, these metal NPs are either embedded in the charge transfer layer such as PEDOT:PSS [4][5][6][7] or simply blended within the active BHJ layer [8][9][10][11] . In the latter approach, NPs coated with organic ligands are typically used to disperse the particles within the organic blends.…”

“…In the latter approach, NPs coated with organic ligands are typically used to disperse the particles within the organic blends. Despite its simplicity, the findings from this approach are highly controversial as both enhancement [8][9][10][11] and detraction 12,13 in organic photovoltaic (OPV) devices performance have been reported. Physical insight into the fundamental photophysics and charge dynamics in these NP-blended plasmonic OPV cells is urgently required.…”

Organic solar cells with plasmonic layers formed by laser nanofabrication

“…8,9 Furthermore recent studies demonstrated that the NPs can lead to an enhancement of the OPV device structural stability as well. [10][11][12] Methods to synthesize and incorporate MNPs are in abundance. Chemical synthesis can give precise control of size, however, it produces a lot of hazardour wastes, 13,14 with a requirement of an additional process step for deposition.…”

Air-processed organic tandem solar cells on glass: toward competitive operating lifetimes

“…As such, future studies should primarily foster materials development of new absorbers with enhanced photo and structural stability as well as alternative electron transport layers that are not subject to the requirement of photodoping. [51][52][53][54] Moreover, fully solution processed tandem OPVs on exible plastics with state-of-the-art encapsulation need to be demonstrated for certifying market readiness.…”