A high-performance dye-sensitized solar cell (DSSC) needs fast electron transport and long electron lifetime in addition to high light-harvesting efficiency. An effective way to enhance the light-harvesting efficiency is to add a light-scattering layer on top of the TiO₂ film in DSSCs. However, such a layer can only scatter light from the top surface, which does not improve the electron-collection efficiency or suppress charge recombination.

Zhong-Sheng Wang, Fudan University, Shanghai, China and colleagues used Au nanoflowers (AuNFs) to enclose the TiO₂ film on all sides, forming a light scattering box (pictured). The nanoflowers improve the light-scattering ability of the photoanode, while at the same time facilitating electron collection and slowing down charge recombination.

According to the researchers, this photoanode configuration can simultaneously improve the short-circuit photocurrent density and the open-circuit photovoltage of DSSCs, thus improving the power conversion efficiency from 8.12 % to 10.91 %.

• Enhancing the Performance of Dye-Sensitized Solar Cells with a Gold Nanoflowers Box,
  Lu Zhang, Zhong-Sheng Wang,
  Chem. Asian J. 2016.
  DOI: 10.1002/asia.201601228