Correlation between the morphology and performance enhancement of ZnO hierarchical flower photoanodes in quasi-solid dye-sensitized solar cells

We report an effective method for mass production of ZnO hierarchical flowers (HFs) that are constructed by interlaced single crystalline ZnO nanosheets with dominant surfaces of {112̄0} and {11̄00}. The size of ZnO HFs, thickness and parking density of the nanosheets, and HF inner porosity can be tuned by changing the synthesis conditions. The HFs containing porous inner structures showed an excellent performance as the photoanode material in quasi-solid (using polymer gel electrolytes) dye-sensitized solar cells (DSCs) because of their superior optical and electrical properties. The high current density (10.26 mA cm^-2) and efficiency (4.93) of the HF-based DSCs indicate a great potential for the development of high-efficient quasi-solid DSCs.