Morphology-controlled growth of Co_3S_4 as highly efficient counter electrode catalysts for dye-sensitized solar cells

摘要

The photoelectric conversion efficiency of dye-sensitized solar cells is affected by the catalytic ability of counter electrode materials. Therefore, it is crucial to develop inexpensive and highly efficient counter electrode materials. In this article, we successfully prepared the Co3S4 with different morphologies (nanosheet and nanoflower). Scanning electron microscopy images display that the Co3S4 nanoflowers have a special spatial structure, which has more reactive sites than the Co3S4 nanosheets. The Co3S4 samples were used as counter electrodes (CEs) for dye-sensitized solar cells (DSSCs), and the photoelectric conversion efficiency of the DSSCs was tested. The DSSC assembled with the Co3S4 nanoflowers CE shows superior power conversion efficiency (PCE) of 7.09% than the Co3S4 nanosheets and Pt CEs under AM 1.5G irradiation, which indicate that the Co3S4 nanoflowers performed outstanding catalytic actives.