含苯并噻二唑的二维有机染料的合成与光伏性能研究

Synthesis and Photovoltaic Properties of Two Dimensional Organic Dyes Containing Benzothiadiazole Unit

通过引入烷基二噻吩苯并噻二唑窄带隙基元到D-π-A有机染料体系中,设计并合成了两种二维结构的有机染料DD2和DH2,系统地研究了以烷基二噻吩苯并噻二唑基元作为侧基或桥联基元对染料敏化剂的光物理性能、电化学性能和光伏性能的影响.含有烷基二噻吩苯并噻二唑基元的这两种染料都具有较宽的吸收光谱.在氙灯光源(100mW?cm-2,AM 1.5 G)下,基于有机染料DH2和DD2的染料敏化太阳能电池的能量转换效率分别为1.67%和3.26%.采用鹅去氧胆酸(CDCA)共吸附剂优化后,染料DH2表现出较好的抗聚集能力,能量转换效率几乎没有变化;而DD2的能量转换效率提高到了5.53%.

By introducing the narrow band gap unit （dithiophene-benzothiadiazole） to the organic dye system, two novel organic dyes （DD2, DH2） with two-dimensional structures were designed and synthesized. The influence of dithiophene-ben- zothiadiazole unit acting as side chain or bridge group on the photophysical, electrochemical, and photovoltaic properties of the two dye-sensitizers was studied systematically. Two as-synthsized dyes with dithiophene-benzothiadiazole unit exhibited broad absorption spectra. Under one sun illumination （100 mW＊cm-2, AM 1.5 G）, DH2- and DD2-based dye-sensitized solar cells showed the power conversion efficiencies （PCE） of 1.67% and 3.26%, respectively. With optimization of co-adsorbent chenodeoxycholic acid （CDCA）, DH2 exhibited a relatvely good anti-aggregation ability. Therefore, CDCA had a negligible effect on the PCE of DH2-based DSSCs. However, DD2 achieved an enhanced PCE of 5.53% after adding CDCA as co-adsorbent.