丝网印刷法制备高催化活性对电极

对电极在染料敏化太阳能电池（DSCs）中主要起催化氧化还原反应及收集电荷的作用，铂对电极常用的制备方法为磁控溅射法，但其成本较高，制备条件苛刻. 本文通过引入低成本的表面活性剂Span-85，所制得的铂对电极的附着力、透光率和均匀性显著改善，实现了面积可控，与两步浸泡法和旋涂热解法制备的对电极在DSCs中的光电转换效率分别为7.30%，6.96%和7.03%. 紫外-可见吸收光谱、扫描电镜和附着力测试等结果表明，（1）添加表面活性剂有利于增加附着力及改善透光率和均匀性；（2）使用该法制备的Pt/FTO对电极的透光率与两步浸泡法制作的相同，且铂粒子分布更加均匀. 电化学阻抗图谱、塔菲尔极化曲线和循环伏安曲线结果表明，丝网印刷方法制备的Pt/FTO对电极具有更加优异的催化性能，且该法更有利于降低其生产成本和大规模生产.

Screen-printed Pt counter electrodes exhibiting high catalytic activity

Counter electrodes (CEs) for dye-sensitized solar cells (DSCs) are important for collecting electrons and catalyzing the iodide/tri-iodide reaction. Pt CEs are commonly prepared by magnetron sputtering, which is expensive and requires vacuum conditions. Incorporating the low cost surfactant Span-85 improved the adhesion between the Pt particles and conductive substrate, and allowed Pt-based CEs to be screen-printed. The screen-printed CE was compared with those prepared by dip-coating and spin-coating. Photoelectric conversion efficiencies of 7.30%, 6.96% and 7.03% were achieved for DSCs containing screen-printed, dip-coated and spin-coated CEs, respectively. Optical transmittance measurements, scanning electron microscopy, and film adhesion tests results showed that the surfactant improved film adhesion and increased transmittance, and the screen-printed CEs exhibited comparable transmittance to the dip-coated CEs. Screen-printing resulted in Pt particles being more uniformly distributed on the substrate, when compared with dip-coating or spin-coating. Cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel-polarization curves showed that the catalytic activity of the screen-printed Pt-based CEs were higher than that of the other CEs. Screen-printing is suitable for realizing the low-cost large-scale production of large Pt-based CEs.