通过引入一种低成本商业导电碳浆(CC)作为粘结剂,以色素碳黑(Cb)作为催化材料,成功制备了Cb-CC对电极.着重解决传统碳对电极的主要问题,即碳与导电基底的附着力问题.附着力测试结果表明:CC的引入改善了Cb与导电基板之间的附着力,同时增强了碳对电极的导电性和稳定性.扫描电镜(SEM)结果显示,CC与Cb混合后,碳膜的多孔结构依然存在,即这种对电极能同时增加导电性和催化活性.采用循环伏安(CV)和电化学阻抗谱(EIS)对Cb-CC对电极的催化活性进行了研究.光电性能测试结果表明,基于Cb-CC染料敏化太阳能电池(DSSC)的能量转换效率达到了6.54%,进一步优化后,当Cb和CC的质量比为23:77时效果最佳,达到最高效率6.81%.此外,基于Cb—CC的DSSC长期稳定性测试结果表明,700h后各项光电参数无明显下降.该实验成果为增强整体电池的稳定性和促进低成本DSSC产业化奠定了基础.
The aim of this study was to resolve the poor bonding strength between carbon film and the conductive substrate in a carbon counter electrode. A carbon black-conductive carbon (Cb-CC) counter electrode was fabricated using a low-cost commercial conductive carbon paste (CC) as a binder and carbon black (Cb) as a catalyst. Film adhesion test results indicated that the introduction of the CC significantly improved the adhesion between Cb and the conductive substrate, as well as the conductivity and stability of the carbon counter electrode. The porous structure of the mixed CC and Cb carbon films was maintained as illustrated by scanning electron microscopy (SEM). Cyclic-voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements showed that the catalytic activity of CC-Cb was superior to that of CC. A dye-sensitized solar cell (DSSC) based on the CC-Cb counter electrode exhibited an excellent photoelectrical performance, reaching an energy conversion efficiency of 6.54%. The amount of CC in the carbon counter electrode was further optimized. Consequently, when the mass ratio of Cb:CC reached 23:77, the corresponding DSSC yielded the highest energy conversion efficiency recorded in this study at 6.81%. In addition, long term stability testing showed that the photovoltaic parameters of the DSSC based on the CC-Cb counter electrode remained similar to the initial values following more than 700 h of light soaking. This work has laid the foundation for improving the stability and the industrialization of low-cost DSSCs.