In situ synthesis of binded, thick and porous carbon nanoparticle dye sensitized solar cell counter electrode with nickel gel as catalyst source

A TiO 2 -embedded NiCl 2 gel is prepared and used as growth catalyst to in situ synthesize binded, thick and porous carbon nanoparticles (CNPs) on Ti foil substrate with a simple flame synthesis method for dye sensitized solar cell (DSSC) counter electrode (CE) applications. The viscous gel catalyst can hold sufficient NiCl 2 coated on substrate to make CNP layer thick. The embedded TiO 2 can effectively separate the abundant NiCl 2 components to active the Ni catalyst for CNP growth and then make CNP layer become porous. In addition, the TiO 2 components can bind the porous CNP products to make them conductive. With an optimized TiO 2 fraction, the CE shows high catalytic ability and electrical conductivity . By applying this CNP CE for DSSC, a photovoltaic conversion efficiency of 6.6% is achieved, which exceeds 6.5% of a reference cell using costly platinum as CE. Furthermore, the CNP structure is demonstrated beneficial to carrier transport by a mass transfer model . This easy and effective preparation method may have a potential application in general nanomaterial preparation.