Unique Gold Nanorods Embedded Active Layer Enabling Strong Plasmonic Effect To Improve the Performance of Polymer Photovoltaic Devices

Abstract

It has been widely reported that plasmonic effects of metallic nanomaterials can enhance light-harvesting in polymer solar cells (PSCs). However, the improved light trapping degree is closely related to the shape of the nanoparticles (NPs), which inevitably limits the efficiency enhancement for PSCs. In this paper, we demonstrate that the incorporation of Au arrowhead nanorods (AHNRs) into the active layer of inverted PSCs can dramatically lead to a 28.7% efficiency enhancement as compared to preoptimize control PSCs. Both theoretical and experimental results show that the origin of the improved power conversion efficiency (PCE) can be attributed to not only the optical absorption enhancement but also charge transport capacity improvement. The metal tip of AHNRs can lead to a significant enhancement of local field and long-range scattering. In addition, a wide-band absorption improvement is observed, and charge carrier mobilities increase by an order of magnitude. These results offer an effective approach to enhance the efficiency for PSCs.

Plasmonic organic bulk–heterojunction solar cells based on hydrophobic gold nanorod insertion into active layers

“…As shown in Figure (a), the control device without added GNRs had a PCE of 7.43%, which is higher than those of P3HT‐ and PCDTBT‐based solar cells, similar to previous PTB7‐based studies. When increasing the amount of GNRs (from 0.15 to 0.45 wt %), the PCEs gradually improved from 7.74% to 8.22%, with the PCE improving by up to 11%.…”

“…The energy‐dispersive spectrometer spectrum shown in Supporting Information Figure S2 further confirmed that the GNRs were protected by DDT. The UV–vis spectrum of the GNRs showed two absorption peaks at wavelengths of 520 and 685 nm . The atomic force microscopy images in Figure (a,b) show that most GNRs were doped inside the PTB7/PC 70 BM layers.…”

“…Using GNRs in poly(3‐hexylthiophene) (P3HT)‐based organic solar cells improved the PCEs by 12.7%–13.9% . Doping gold arrowhead nanorods into the active layer of poly[ N ‐9′‐heptadecanyl‐2,7‐carbazole‐ alt ‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT)‐based organic solar cells improved the PCEs from 5.75% to 6.81% . Compared with P3HT‐ and PCDTBT‐based devices, organic solar cells using PTB7 showed a higher PCE.…”

“…Compared with P3HT‐ and PCDTBT‐based devices, organic solar cells using PTB7 showed a higher PCE. Thus, it is very important to investigate the plasmonic effect of GNRs on the performance of PTB7‐based organic solar cells . So far, a study of depositing silica‐coated GNRs onto anode buffer layers enhanced the PCE from 6.69% to 7.45% for PTB7‐based organic solar cells .…”

Nanostructures induced light harvesting enhancement in organic photovoltaics

“…The material, shape, size, concentration, composition and location of incorporated metal NPs are key parameters to tailor the resonant frequency and coupling efficiency of LSPR in OPVs. For example, Guo et al [126] reported the application of Au arrowhead nanorods (ARNRs) in the inverted polymer OPVs based on PCDTBT and PC 71 BM, and the PCE was improved from 5.75% to 7.40% with a maximum enhancement of 28.7%. Except for exciting the LSPR, the ARNRs in the active layers also reduced the cell resistance and improved the charge transport as demonstrated by the experimental and theoretical analyses.…”