TiO2 film decorated with highly dispersed polyoxometalate nanoparticles synthesized by micelle directed method for the efficiency enhancement of dye-sensitized solar cells

In this work, two kinds of polyoxometalate (POM) nanoparticles with controlled shapes and structures were synthesized by micelle directed method and then composited with TiO 2 via calcination to remove the surfactants owing to the excellent electronic storage and transmission ability of POM, finally obtaining two kinds of TiO 2 composites with highly dispersed and small-sized POM nanoparticles (∼1 nm). The TiO 2 composites were then induced into the photoanodes of dye-sensitized (N719) solar cells (DSSCs). The separation of electron-holes becomes more favorable due to the nanostructure and high dispersion of POM which provide more active sites than pure POM tending to agglomeration. The TiO 2 composite photoanodes finally yielded the power conversion efficiency (PCE) of 8.4% and 8.2%, respectively, which were 42% and 39% higher than the pristine TiO 2 based anodes. In addition, the mechanisms of POM in DSSC are proposed.