纤维状纸炭对电极构造的准固态染料敏化太阳电池

Quasi-solid-state Dye-sensitized Solar Cells Employing Fibers Stacked Paper Carbons as Efficient Counter Electrodes

将三种纸张(复印纸、滤纸和面巾纸)为原料经单步热解获得的纸炭作为对电极的催化材料引入准固态染料敏化太阳电池(QDSCs),考查了纸炭的催化活性和相应器件的光电性能。结果表明:三种纸炭均由径向尺寸约为10μm的碳纤维堆砌而成,具有低的结晶度和发达的孔隙,因此相比石墨均能获得更佳的催化活性和更高效率的QDSCs。在三种纸炭中,由复印纸获得的纸炭所含的碳纤维表面具有独特的细小鳞片结构,使其拥有最高的比表面积和最优的催化活性。纸炭在QDSCs中既能提供催化活性点,又能改善电解质的离子导电率,因此获得高于铂对电极组装的QDSCs的短路电流和开路电压,弥补了催化活性和填充因子的不足,最终具有与后者相比拟的光电转换效率。

Three types of paper carbons （PCs） were introduced into quasi-solid-state dye-sensitized solar cells （QDSCs） as counter electrodes. The PCs were respectively prepared using printed paper, filter paper and facial tissue as raw materials by one-step pyrolysis. Results show that each PC consists of carbon fibers with radial size of -10 pro, and has low crystallinity as well as well-developed porous structure. As a result, each type of PC displays more excellent catalytic activity for tri-iodide （ I3 ） reduction than graphite, which brings about higher efficiency for use in QDSCs. In three PCs, PC fabricated from printed paper possesses the highest surface area and the most outstanding catalytic activity. This is mainly attributed to unique carbonaceous ramentums on carbon fibers in printed paper derived PC. Each type of PC in QDSCs not only provides catalytic active sites for I3 reduction, but also serves distinctive function to improve the ion conductivity of quasi-solid-state electrolyte. Consequently, PCs based QDSCs have higher short-circuit current density （Jsc） and open-circuit voltage （Voc） compared with traditional Pt based QDSCs. The higher Jsc and Voc cover the insufficiency of fill factor, resulting in comparable efficiencies with traditional Pt based QDSCs.