Properties of the scattering layer inserted dye sensitized solar cells

We propose a working electrode with a scattering layer inserted for dye-sensitized solar cells (DSSCs) with the following structure: glass/FTO/blocking layer/TiO₂scattering layer/dye/electrolyte/Pt/ FTO/glass. A working electrode without a scattering layer was also prepared using a similar method for comparison. The microstructure was examined by optical microscopy and field emission scanning electron microscopy (FE-SEM). The photovoltaic properties, such as the short circuit current density (Jsc), open circuit voltage (Voc), fill factor (FF), energy conversion efficiency (ECE) and impedance were characterized using a solar simulator and potentiostat. FE-SEM confirmed that the blocking layer with 20 nm grains and the scattering layer with 350-450 nm grains had been prepared. The Jsc and Voc increased, and impedance analysis revealed a decrease in the electron transfer resistance and electron recombination resistance at the TiO₂/electrolye interface. The ECE with the scattering layer was 6.35%, which was 20% higher than that observed in the ECE without the scattering layer.