Papilio bianor wings modified with gold nanoparticle enhance light absorption in dye-sensitized solar cells

The microscopic structure of living things in nature is the inspiration for many human science and technology, and the structural color of butterfly wings has been applied in many fields. In the field of solar cells, butterfly wings have been successfully replicated and applied to dye-sensitized solar cells (DSSC).However, the improvement of power conversion efficiency of DSSC with only one bionic structure is limited. So combining the local surface plasmon resonance (LSPR) effect with the nanostructure of bionic butterfly wings in DSSC is expected to achieve higher power conversion efficiency. In this paper, taking dye-sensitized solar cells as the research object, a novel composite structure has been developed and applied to the photoanode, and the power conversion efficiency of the device has been significantly improved. First of all, The LSPR effect of gold nanoparticles was verified by simulation analysis using FDTD Solutions. The gold colloid with the particle size of 30 nm was prepared by sodium citrate reduction method, and the gold colloid was introduced in the process of replicating the wings of Papilio bianor. The gold nanoparticle modified TiO₂-BW (Au/TiO₂-BW) was obtained and applied to the photoanode of DSSC. The results showed that compared with the DSSC prepared by ordinary P25 photoanode, the power conversion efficiency of DSSC prepared by Au/TiO₂-BW photoanode increased by about 17%. Thanks to the synergistic effect of the microstructure of Papilio bianor wings and the LSPR effect, the light absorption capacity of the photoanode was enhanced, and the J_SC was effectively improved. At the same time, the introduction of Au/TiO₂-BW can effectively inhibit charge recombination and promote carrier transport.