O'Regan Brian C, Durrant James R
J Phys Chem B. 2006 May 4;110(17):8544-7. doi: 10.1021/jp060979w.
Transient photovoltage and photocurrent measurements have been employed to determine the recombination and transport kinetics in operating dye-sensitized photovoltaic cells as a function of potential and temperature. Photocurrent transients have been taken at the open circuit potential, as opposed to the standard measurement at short circuit. Kinetic results have been used to calculate the activation energy as function of the Fermi level position in the TiO(2). In the calculation of activation energies, we have explicitly taken into account the temperature dependence of the offset between the electrolyte redox potential and the conduction band edge. This new method gives activation energies that decrease linearly as the Fermi level position moves toward the conduction band edge, as expected, but not found in previous studies. The results are consistent with the presence of a distribution of traps below the TiO(2) conduction band, the detrapping from which limits both the transport and the recombination of electrons.
瞬态光电压和光电流测量已被用于确定工作中的染料敏化光伏电池中的复合和传输动力学，作为电势和温度的函数。光电流瞬态是在开路电势下获取的，这与短路时的标准测量相反。动力学结果已被用于计算作为TiO₂中费米能级位置函数的活化能。在活化能的计算中，我们明确考虑了电解质氧化还原电势与导带边缘之间偏移的温度依赖性。这种新方法给出的活化能随着费米能级位置向导带边缘移动而线性降低，正如预期的那样，但在以前的研究中未发现。结果与TiO₂导带下方存在陷阱分布一致，从这些陷阱中脱陷阱限制了电子的传输和复合。
