Application Of Polypyrrole And Its Polyoxometalate Hybrid Electrodes In Dye-sensitized Solar Cells

Dye-sensitized solar cell(DSSC) has a rapid development in recent 20 years. As a new type of solar cell, DSSC has become a hotspot in the field of photovoltaic due to its environment-friendly, simple fabrication technology, and high efficiency. In this system, the role of counter electrode(CE) is an electron collector and transporter, as well as a catalyst of the redox couples regeneration. Pt Usually played the role as a counter electrode. However, Pt is so precious that it’s difficult to realize the DSSC industrialization. Therefore, in order to reduce cost and improve the power conversion efficiency(PCE), it’s necessary to explore Pt-free CE. Conductive polymers has the advantages of high conductiyity and low price, while polyoxometalate usually used to improve the catalytic activity of electrode. Therefore,This paper based on the application of conductive polymers and its polyxoxmetalate hybridelectrodes in DSSC. The main works and results are listed:1. Polypyrrole nanosheet(PPy-Sheet) film and polypyrrole nanosphere(PPySphere) film are successfully synthesized by electropolymerization method.Compared with PPy-Sphere CE, the PPy-Sheet CE shows obviously enhanced electrochemical catalytic activity. The DSSC based on PPy-Sheet CE achieves a PCE of 5.29 %, which is higher than the solar cell based on PPy-Sphere CE(5.04 %).Compared with traditional chemical synthesis of polypyrrole, the preparation of electrodeposition method is more simple, and obviously shorten the period of production.2. A phosphotungstic acid doped polypyrrole(PW12-PPy) hybrid film is successfully synthesized by electropolymerization method. The PW12-PPy CE possessed the advantage of pure PPy CE, such as good conductivity and high surface asperities. The DSSC based on PW12-PPy CE achieves a PCE of 6.19 %, which is higher than the solar cell based on PPy CE(5.04 %), and comparable with the solar cell based on Pt CE(6.25 %). Compared with the traditional synthesis, which is called as Two Step, the preparation of compound electrodes, simplifies the technology,as well as saves the cost of production.3. A(K8[α-SiW11O39]·12.7H2O)-doped PPy hybrid film(denoted as SiW11-PPy)is successfully fabricated via electropolymerization method. The SiW11-PPy CE shows higher catalytic activity than PPy-Sheet CE, and the DSSC based on SiW11-PPy CE achieves a PCE of 6.35 %, which is higher than the solar cell based on PPy-Sheet CE(5.29 %) and Pt CE(6.25 %). Compared with the traditional synthesis,which is called as Two Step, the preparation of compound electrodes, simplifies the technology, as well as saves the cost of production. What’s more, SiW11 improves the catalytic activity of PPy-Sheet.