The influence of non-radiative relaxation on the room-temperature phosphorescence of metalloporphyrin

作者：Liu, Lixin^*; Han, Bo^*; Cao, Yu; Wen, Jingji

来源：Journal of Porphyrins and Phthalocyanines, 2022, 26(12): 884-890.

DOI：10.1142/S1088424622500833

• metalloporphyrin
• phosphorescence
• absorption
• energy level structure
• spectroscopy

The room-temperature phosphorescence (RTP) of metalloporphyrins, induced by the heavy atom effect (HAE), has been widely concerned in many fields, and the intense emission of RTP is highly desired. The phosphorescent transition rate (k(P)) has been used to quantitatively characterize the HAE's intrinsic nature. However, the phosphorescent intensity was not determined by k(P) alone, non-phosphorescent transition (k(nP)) induced by surrounding factors was also involved. In this study, the influence of k(nP) on the RTP of palladium octaethylporphyrin (PdOEP), platinum octaethylporphyrin (PtOEP), and platinum tetraphenylporphyrin (PtTPP) was studied. The effect of k(nP) can be quantitatively described by an introduced parameter eta, which was defined as eta = k(P)/(k(P) + k(nP)). The method is proposed for determining the eta of PdOEP, PtOEP, and PtTPP by the UV-visible absorption spectra, luminescence spectra, and phosphorescence dynamic curves. Our research provides a way to understand the effect of knP on the RTP, and may benefit the development and optimization of metalloporphyrins aiming at intense RTP.

• 单位
  哈尔滨医科大学; 哈尔滨商业大学