The effect of gold quantum dots/grating-coupled surface plasmons in inverted organic solar cells

Abstract

We studied the effect of gold quantum dots (AuQDs)/grating-coupled surface plasmon resonance (GC-SPR) in inverted organic solar cells (OSCs). AuQDs are located within a GC-SPR evanescent field in inverted OSCs, indicating an interaction between GC-SPR and AuQDs' quantum effects, subsequently giving rise to improvement in the performance of inverted OSCs. The fabricated solar cell device comprises an ITO/TiO 2 /P3HT : PCBM/PEDOT : PSS : AuQD/silver grating structure. The AuQDs were loaded into a hole transport layer (PEDOT : PSS) of the inverted OSCs to increase absorption in the near-ultraviolet (UV) light region and to emit visible light into the neighbouring photoactive layer, thereby achieving light-harvesting improvement of the device. The grating structures were fabricated on P3HT:PCBM layers using a nanoimprinting technique to induce GC-SPR within the inverted OSCs. The AuQDs incorporated within the strongly enhanced GC-SPR evanescent electric field on metallic nanostructures in the inverted OSCs improved the short-circuit current and the efficiency of photovoltaic devices. In comparison with the reference OSC and OSCs with only green AuQDs or only metallic grating, the developed device indicates enhancement of up to 16% power conversion efficiency. This indicates that our light management approach allows for greater light utilization of the OSCs because of the synergistic effect of G-AuQDs and GC-SPR.

Plasmonic photothermal properties of silver nanoparticle grating films

“…Furthermore, for the grating pitch of 740 nm, two surface plasmon dips were observed at incident angles of 5°, 10°, and 15° (at approximately 750/840, 690/930, and 620/1000 nm, respectively), which correspond to the propagating surface plasmon mode number m = +SP −1 and −SP +2 modes. 34 As shown in Fig. 4(c), the reflectivity of the AgNP grating film ( Λ = 740 nm) is determined to be extremely low in a wide range of wavelengths.…”

Gold nanostructures/quantum dots for the enhanced efficiency of organic solar cells

“…In our reports, GCSPR, 78,105–108 dual or multiple SPR-based GCSPR-integrated AuNPs, 73 and AuQDs 37,109 were demonstrated to significantly enhance the photocurrent in OSCs. The LSPR and GCSPR of hybrid plasmonics generally exhibit manifest characteristics and narrow resonance wavelength regions, which could broaden light absorption within photovoltaic devices.…”

Tunable surface plasmon resonance enhanced fluorescence via the stretching of a gold quantum dot-coated aluminum-coated elastomeric grating substrate

“…, the fluorescence of the AuQDs was enhanced by the fluorescence-induced SPR excitation of the AuQDs. 43,45 However, the fluorescence intensity of the AuQDs decreased at a fixed incident angle of 40° as the substrate was stretched from 0 to 1.0 mm, as shown in Fig. 7c.…”

“…Therefore, the increased uorescence intensity is thought to be due to the SPR enhancement at around the uorescence peak wavelength of 512 nm, 50,51 generated by the illumination from the uorescence of AuQDs, i.e., the uorescence of the AuQDs was enhanced by the uorescence-induced SPR excitation of the AuQDs. 43,45 However, the uorescence intensity of the AuQDs decreased at a xed incident angle of 40 as the substrate was stretched from 0 to 1.0 mm, as shown in Fig. 7c.…”

“…4 The unique optical properties of the AuQDs mean that they exhibit uorescence emission in the visible region when excited from the near ultraviolet (UV) to blue light region, attributed to quantum effects due to the ultrasmall size of a few atoms (5-25 Au atoms) that have a particle size of <2 nm. [39][40][41] AuQDs have also been used in several applications, such as optical sensors, 42 solar cells, [43][44][45][46] and biosensors. 47,48 However, there have been no reports on tunable uorescence enhancement by controlling the SPR wavelength using a tunable elastomeric metallic-grating substrate.…”