Getting to the (Square) Root of the Problem: How to Make Noncoherent Pumped Upconversion Linear
Getting to the (Square) Root of the Problem: How to Make Noncoherent Pumped Upconversion Linear
复制标题
DOI：
10.1021/jz300012u
复制
发表时间：
2012-02-02
影响因子：
5.7
通讯作者：
Castellano, Felix N.
中科院分区：
文献类型：
--
作者：
Haefele, Alexandre;Blumhoff, Joerg;Castellano, Felix N.
我们给出的实验数据表明，基于敏化的三重态三重态湮没的光化学上转换可以表现出反斯托克斯发射，其强度相对于激发功率的变化可以在非相干多色光源下在二次和线性之间变化。选择由Pd(II)八乙基卟啉(PdOEP)敏化剂和9，10-二苯基菲(DPA)受体/湮灭剂组成的基准上转换化合物，在相干和非相干激发条件下产生二次、中间和线性行为。在一个连续的实验中，通过使用Ar+激光选择性地泵浦增感剂，在单个样本中通过这些幂定律中的每一个。在常规荧光计中用氙灯/单色仪输出激发时，同样的样品成分也记录了从二次到伪线性的波长相关响应，其中波长(Ex)处的光密度决定了观察到的入射功率相关性。最后，在较高的敏化剂浓度下，首次从非相干激发得到了纯的线性行为。
We present experimental data illustrating that photochemical upconversion based on sensitized triplet triplet annihilation can exhibit anti-Stokes emissions whose intensities with respect to the excitation power can vary between quadratic and linear using a noncoherent polychromatic light source. The benchmark upconverting composition consisting of Pd(II) octaethylporphyrin (PdOEP) sensitizers and 9,10-diphenylanthracene (DPA) acceptors/annihilators in toluene was selected to generate quadratic, intermediate, and linear behavior under both coherent and noncoherent excitation conditions. Each of these power laws was traversed in a single sample in one contiguous experiment through selective pumping of the sensitizer using an Ar+ laser. Wavelength-dependent responses ranging from quadratic to pseudolinear were also recorded from the identical sample composition when excited by Xe lamp/monochromator output in a conventional fluorimeter, where the optical density at lambda(ex) dictates the observed incident power dependence. Finally, pure linear behavior was derived from noncoherent excitation for the first time at higher sensitizer concentrations.