Efficiency Enhancement of Organic Solar Cells by Using Shape‐Dependent Broadband Plasmonic Absorption in Metallic Nanoparticles

Abstract

It is been widely reported that plasmonic effects in metallic nanomaterials can enhance light trapping in organix solar cells (OSCs). However, typical nanoparticles (NP) of high quality (i.e., mono‐dispersive) only possess a single resonant absorption peak, which inevitably limits the power conversion efficiency (PCE) enhancement to a narrow spectral range. Broadband plasmonic absorption is obviously highly desirable. In this paper, a combination of Ag nanomaterials of different shapes, including nanoparticles and nanoprisms, is proposed for this purpose. The nanomaterials are synthesized using a simple wet chemical method. Theoretical and experimental studies show that the origin of the observed PCE enhancement is the simultaneous excitation of many plasmonic low‐ and high‐order resonances modes, which are material‐, shape‐, size‐, and polarization‐dependent. Particularly for the Ag nanoprisms studied here, the high‐order resonances result in higher contribution than low‐order resonances to the absorption enhancement of OSCs through an improved overlap with the active material absorption spectrum. With the incorporation of the mixed nanomaterials into the active layer, a wide‐band absorption improvement is demonstrated and the short‐circuit photocurrent density (Jsc) improves by 17.91%. Finally, PCE is enhanced by 19.44% as compared to pre‐optimized control OSCs. These results suggest a new approach to achieve higher overall enhancement through improving broadband absorption.

Nanostructures induced light harvesting enhancement in organic photovoltaics

“…Plasmonic nanostructures, such as periodic metal gratings [88][89][90], metal NPs [91][92][93][94], random corrugations [95][96][97] and biomimetic structures [98][99][100], have been investigated universally involving light concentration and manipulation in OPVs. Various kinds of plasmonic nanostructures can effectively trap light inside the photoactive layer owing to the excitation of the surface plasmonic effect, which is the collective oscillations of conductive electrons at the metal/dielectric interface.…”

“…Choy et al [92] demonstrated broadband light trapping in OPVs with multi-plasmonic-resonant absorption peaks based on metal NPs. They incorporated Ag NPs and nanoprisms with different shapes synthesized by a wet chemical method in P3HT:PCBM photoactive layers as shown in Figure 8D and E, and low-order and high-order plasmonic resonance modes were excited simultaneously in broadband.…”

Morphological Control Agent in Ternary Blend Bulk Heterojunction Solar Cells

“…Inorganic nanocrystals (INCs) can also be included into BHJ film, which is an extensively adopted strategy to enhance device performances [65][66][67][68][69]. The main focus lies on their unique plasma effects for enhancing light scattering path within the thin films.…”

Effect of Silver Nanoparticles with Indium Tin Oxide Thin Layers on Silicon Solar Cells

“…Therefore, there was an amount of attempts to enhance light emitting diodes (LED) based on particular wavelength [4,5]. However, the enhancement of light is the issue not only for the LED, but also for the many kinds of photonic devices including solar cells [6][7][8].…”