Facile and rapid preparation of platinum counter electrodes for dye-sensitized solar cells

• Pt nano particles are prepared by chemical reduction of a Pt precursor.
• The Pt nanoparticles are deposited on FTO substrates.
• The platinized FTOs are used as counter electrodes in dye-sensitized solar cells.
• The method of fabricating the counter electrodes is facile and low-temperature.
• The method is suitable for fabricating flexible Pt electrodes.

Here, we report on the deposition of platinum nanoparticles (PNPs) on fluorine-doped tin oxide (FTO) substrate by synthesizing PNPs through chemical reduction of potassium tetrachloroplatinate with formic acid, and subsequently depositing the PNPs on FTO substrate at 70 °C; and application of the chemically reduced Pt electrodes (CRs) as the counter electrodes (CEs) of dye-sensitized solar cells (DSSCs). The surface morphology and catalytic activity of the prepared CRs were studied along with conventional thermally decomposed Pt electrodes (TDs). Electrochemical study showed that the catalytic performance of the CRs toward the reduction of I3− was comparable to that of TDs. Also, the photovoltaic performance of the DSSCs with CRs were similar to that with TDs. The method of preparing Pt electrodes through chemical reduction is so fast that the whole process of preparing a set of CRs, after pre-cleaning of the FTO substrates, takes less than 30 min. Most importantly, the present method enables low temperature fabrication of Pt electrodes even on flexible substrates.