Dual-template synthesis of N-doped macro/mesoporous carbon with an open-pore structure as a metal-free catalyst for dye-sensitized solar cells

Dye-sensitized solar cells (DSSCs) have attracted world-wide attention due to their low cost, high conversion efficiency, and environmental friendliness. Pt catalyst is usually used as the catalyst in the counter electrode of DSSCs due to its high electrochemical catalytic activity toward tri-iodide reduction. However, the high cost and scarcity of Pt prevent its large-scale application in DSSCs. It is highly desirable to replace Pt with low-cost catalysts made from earth-abundant elements. Here, we report a dual-template synthesis of N-doped macro/mesoporous carbon (macro/mesa-NC) with an open-pore structure as the catalyst in the counter electrode of DSSCs. The catalytic activity of macro/meso-NC toward triiodide reduction has been tested by cyclic voltammetry (CV) and photocurrent-voltage (J-V) curves. It is found that the macro/meso-NC possesses excellent electrochemical catalytic activity with higher open-circuit voltage and cell efficiency than Pt. A high energy conversion efficiency of 7.27% has been achieved based on the metal-free macro/mesa-NC, demonstrating as a promising catalyst for low-cost DSSCs. (C) 2015 Elsevier B.V. All rights reserved.