Plasmonic dye-sensitized solar cells through collapsible gold nanofingers

Abstract

Plasmonic nanostructures are successfully demonstrated in solar cells due to their broad spectra-selective resonance in the range of ultraviolet to near-infrared, and thus light absorption can be mostly improved and power conversion efficiency (PCE) further. Here, we demonstrate plasmonic dye-sensitized solar cells (DSSCs) using collapsible Au nanofingers to build photoanode to enhance light absorption. In this plasmonic DSSCs, by balancing local field enhancement due to gap-plasmon resonance and dye fluorescence quenching, the optimal gap size in collapsed Au/Al2O3/Au nanofingers is designed by twice the Al2O3 thickness and then deposited a TiO2 layer as photoanode. The results show that the PCE of DSSCs is mostly improved as compared to DSSCs with photoanode of Au/Al2O3/TiO2 films, which can be ascribed to the coupled local field enhancement within the sub-nanometer gaps. In addition, fluorescence of dyes on plasmonic nanofingers is nearly 10 times higher than plain Au/Al2O3/TiO2 films, which further proves the dye absorption enhancement. These plasmonic nanofingers enable the precise engineering of gap-plasmon modes and can be scaled up to wafer scale with low cost by the nanoimprint lithography technique, which suggests the feasibility of applying our result in constructing the photoanode for other types of solar cells.

Hybrid Tuning of Sub‐Filaments to Improve Analog Switching Performance in Memristive Devices

“…Al 2 O 3 in the switching layer was grown at 80 °C using atomic-layer deposition (ALD) that is able to control film thickness at atomic precision. [35,36] One nanometer Pt and 2 nm Ti layers inside the switching layer were deposited by electron-beam metal evaporator. Here 1 nm Pt is ultra-thin and this layer can hardly been characterized by scanning electron microscope (SEM) due to the limited contrast of SEM.…”

High Anti-Reflection Large-Scale Cup-Shaped Nano-Pillar Arrays via Thin Film Anodic Aluminum Oxide Replication

“…With light as the main medium of solar cells, the light reflection loss at the interface between high and low refractive index is inevitable, which is one of the main reasons for the low efficiency of solar cells at present. Nanostructured solar cells with advantages of high local electric field [ 8 , 40 ], wide operating wavelength [ 24 , 41 ], and omnidirectionality [ 24 , 41 ] have been expected as an ideal solution in recent years. Therefore, a thin film solar cell model was built to further study the light-trapping performance of the CSNP.…”