| Abstract:Dye sensitized solar cells (DSSCs) have attracted great attention due to their low cost fabrication and high performance. However, to commercialize DSSCs, both long term stability and efficiency should be further improved. In this regard, conjugated polymer dyes draw our interests. On the basis of previous study on dye PAC-01, two series of double donors’conjugated polymers were designed and synthesized through structural modifications. Then polymer dyes were applied to fabricate devices and the relationships between the structure and performance were deeply investigated through spectral, electrochemical, and photovoltaic experiments. I hope this work could help to shed light on future rational design of polymer dyes for more efficient dye-sensitized solar cells.The details are as follows:(1)Firstly, the thiophen conjugated unit in PAC-01was replaced by3,4-ethylenedioxythiophene (EDOT) to get PAC-02, and then an extra thiophene was introduced to get PAC-03. The result shows that the introduction of electron-rich EDOT unit doesn’t promote photovoltaic propertities, but the extension of π units could lead to red-shift in spectra and better light harvesting capacity.Besides, the optical band gap decreases and the IPCE peak increases. The light response range red shift and the short circuit current (Jsc), open circuit voltage (Voc) and the overall energy conversion efficiency increase.(2)The co-donor units of PAC dyes were optimized by replacing carbozole with phenothiazine to get another series of polymer dyes, namely PAT-01, PAT-02and PAT-03. UV-vis absorption spectra prove that the introduction of phenothiazine contributes to strong and wide absorption in the visible area. As a result, the devices based on PAT dyes show higher IPCE and Jsc, and especially dyePAT-03base device gets a high Jsc of10.87mA·cm-2and overall conversion efficiency of4.71%. |
PDF Full Text Request