Hierarchical porous carbon derived from rice husk as a low-cost counter electrode of dye-sensitized solar cells

The porous carbon with a high surface area is prepared from rice husk through pyrolysis and chemical activation and explored as the counter electrode of dye-sensitized solar cells. Structure and texture analysis reveals that the as-prepared porous carbon has a hierarchical porous structure containing large-size mesopores and abundant micropores. Electrochemical studies indicate that the obtained hierarchical porous carbon electrode has high electrocatalytic activity for I−/I3− redox reaction and enhanced electrolyte diffusion capability. These enhanced electrochemical properties are beneficial for improving the photovoltaic performance of dye-sensitized solar cells. Under irradiation of 100 mW cm−2, the dye-sensitized solar cell with this porous carbon counter electrode shows a conversion efficiency of 6.32%, which is closed to that of the cell with Pt electrode (6.69%). These promising results highlight the potential application of hierarchical porous carbon derived from rice husk in more cost-effective dye-sensitized solar cells.