2,5-Thiophene substituted spirobisiloles – synthesis, characterization, electrochemical properties and performance in bulk heterojunction solar cells
作者:Kassem Amro、Anil K. Thakur、Joëlle Rault-Berthelot、Cyril Poriel、Lionel Hirsch、William E. Douglas、Sébastien Clément、Philippe Gerbier
DOI:10.1039/c2nj40535k
日期:——
New spirobisilole molecules containing thienyl (DTSBS) and bis-thienyl (BBTSBS) electron donor groups have been synthesized for use as the donor material in bulk-heterojunction solar cells together with PCBM. The spectroscopic, electrochemical and thermal properties of DTSBS and BBTSBS have been investigated. All these new spirobisiloles exhibit excellent thermal stability. Cyclic voltammetry measurements revealed reversible and irreversible oxidation and irreversible reduction processes. The highest occupied and lowest unoccupied molecular orbital (HOMO/LUMO) energy levels were determined from electrochemical measurements and DFT calculations. The HOMO/LUMO energy levels were estimated to lie in the range of â5.2 to â2.3 eV for DTSBS and â4.9 to â2.6 eV for BBTSBS. For both compounds, electropolymerization processes occur at potentials higher than 1.5 V leading to low band gap electrogenerated polymers. Spin-coating-deposited bulk-heterojunction solar cells fabricated with the novel spirobisiloles as donor and PCBM as acceptor displayed open-circuit voltages up to 0.4 V, short-circuit currents around 0.5 mA cmâ2, and power conversion efficiencies approaching 0.1%.
我们合成了新的螺双硅氧烷分子,其中包含噻吩(DTSBS)和双噻吩(BBTSBS)电子供体基团,与PCBM一起用作异质结太阳能电池中的供体材料。我们对DTSBS和BBTSBS的光谱、电化学和热性质进行了研究。所有这些新的螺双硅氧烷都具有优异的热稳定性。循环伏安法测量揭示了可逆和不可逆氧化以及不可逆还原过程。通过电化学测量和DFT计算确定了最高占据和最低未占据分子轨道(HOMO/LUMO)能级。据估计,DTSBS的HOMO/LUMO能级在-5.2至-2.3 eV之间,BBTSBS的HOMO/LUMO能级在-4.9至-2.6 eV之间。对于这两种化合物,电聚合作用发生在高于1.5 V的电位下,从而形成带隙小的电致聚合物。用新型螺双硅氧烷作为供体和PCBM作为受体制造的旋涂沉积异质结太阳能电池的开路电压高达0.4 V,短路电流约为0.5 mA cm-2,功率转换效率接近0.1%。