Work

Determination of the T 1 state energy levels of metalloporphyrins using temperature-dependent time resolved spectroscopy

Year: 2025

Type: article

Abstract: The determination of the energy of the lowest triplet excited state ( E T1 ) for metalloporphyrin photosensitizers, a key parameter for rationalizing energy transfer processes in metalloporphyrins, facilitates a better understanding and optimization of their functionality. In this study, a strategy was proposed for determining the E T1 values in metalloporphyrin systems by analyzing the temperature dependence of the oxygen quenching rate constant using time-resolved spectroscopy, with Platinum(II) octaethylporphyrin (PtOEP) and Palladium(II) octaethylporphyrin (PdOEP) as representative examples. Through a thermal equilibrium approximation of the excited triplet state (T 1 ) and the excited state of oxygen, a theoretical model was introduced in which the oxygen quenching rate exhibits a nonlinear dependence on temperature, enabling the determination of E T1 values. Additionally, the validity of this approach was demonstrated through excitation spectra of metalloporphyrins. Our work provides an effective pathway and offers new insights into the energy-loss mechanisms involved in related photoconversion processes.

Source: Optics Express

DOI: 10.1364/oe.561134

Authors: Lu Li, Feng Qin, Zhiguo Zhang, Tao Jia

Institution: Northeast Forestry University

Language: English

Topic: Porphyrin and Phthalocyanine Chemistry

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,270

Funder: National Natural Science Foundation of China