Zinc Porphyrin Sensitizers Containing Different Withdrawing and Donating Groups for Dye-sensitized Solar Cells: Design,Synthesis and Photovoltaic Properties

In this work, a series of unsymmetrical push-pull type zinc-porphyrins, in which meso-substituted porphyrin core bears an electron-donating group and an electron-withdrawing group in the trans positions, have been designed and synthesized to improve the light-harvesting in dye-sensitized solar cells(DSSCs). The electronic structures of these zinc-porphyrin dyes were firstly screened by using density functional theory(DFT) and time-dependent density functional theory(TDDFT) calculations. Among these zinc-porphyrin derivatives, zinc porphyrins bearing a phenyl, diphenyl-benzenamine or 3-nitro-benzoic acid substituent, denoted D1, D2 or D3, respectively, are found to exhibit superior HOMO and LUMO locations which are suitable for DSSCs systems. In particular, the η value of the DSSCs(D2) improved up to 2.3 times when compared with reference cell(D1) on account of the increase of Jsc, FF and Voc. The enhancement of cell performance arises from the effective charge separation and decreases the aggregation of porphyrin dyes.     

0.5 eV时H++D2(v=0,j=0) 反应的微分、积分截面

基于ab initio势能面(KBNN PES)[1],用耦合通道超球坐标理论研究了碰撞能等于0.5 eV时H D2(v=0,j=0)的积分,微分截面.对于反应性碰撞,计算的积分截面表明由于深势阱的存在使得这一绝热反应产物的分布表现出一种近似的统计行为.计算的微分截面反映该体系存在着长寿命的中间络合物;对于非反应性碰撞(传能过程),平动—平动传能过程更有效,且其积分截面随着转动量子数的增大而显著减少.通过反应性碰撞和非反应性碰撞积分截面的比较,发现在低能碰撞情况,非反应性碰撞更容易进行.