Room temperature phosphorescence of organic compounds. The effects of moisture, oxygen, and the nature of the support-phosphor interaction

Abstract

The effects of moisture, 02, and the nature of the support-phosphor interaction on room temperature phosphorescence (RTF) of sodium 4-biphenylcarboxylate and sodium 1-naphthoate (polar organic compounds) adsorbed on paper, sucrose, starch, glass fiber paper, silanized paper, and others were studied. It is found that an abundance of surface hydroxyl groups are necessary for a suitable RTF support, and the presence of moisture in the atmosphere serves to both allow collisional deactivation of the excited phosphor and permit increased quenching by aiding in the transport of 02 into the sample matrix. The results support the hypothesis that hydrogen bonding of the phosphor to the support is the primary mechanism of preventing collisional deactivation of the excited phosphor by restricting translational, vibrational, and rotational movements, and a sample matrix is set up which resists the penetration and subsequent quenching effects of 02.

Characteristics of Phosphorescence of Ionic Organic Compounds Adsorbed on Filter Paper

“…g., environmental research, forensic science, pharmaceutical analysis, biochemistry, medicine, and clinical chemistry; about 300 reports on the RTP applications have been published until now 12, 3,41. In spite of its wide applications, relatively little is known about the mechanism that leads to RTP, except that hydrogen bonding between phosphorescent molecules and hydroxyl groups of filter paper is primarily needed [5].…”

Crystallization-Induced Phosphorescence for Purely Organic Phosphors at Room Temperature and Liquid Crystals with Aggregation-Induced Emission Characteristics

“…Figure 2.7 illustrates temperature-variable wide-angle X-ray diffraction (WAXD) diagrams for P32 (10), from which mesophase formation and the developing processes can be traced. Apparently, at 30 C, three peaks and one diffuse halo at 2u ¼ 2.63, 5.47, 7.77, and 20.76 are observed.…”

“…nature of the electrons in metal-free organic materials leaves them little freedom and less impetus to emit from triplet states [9]; second, the singlet-triplet mutual transitions are spin-forbidden; thirdly, molecular motions can effectively annihilate the triplet state excitons during their long residence time through detrimental processes such as thermal perturbations, intramolecular motions, solute-solute and solute-solvent collisions, and intermolecular interactions with quenching moieties such as oxygen and humidity [10]. Therefore, phosphorescence from purely organic luminogens has usually been observed under conditions free from the above interfering effects, typically at cryogenic temperatures (e.g.…”

Fiber optic sensors using novel substrates for hydrogen sulfide determination by solid surface fluorescence

“…Rather little is understood about the physicochemical interactions that are responsible for RTL on filter paper. Schulman and Parker [27] proposed that, hydrogen bonding of the ionic organic molecules to hydroxyl groups on the support is the primary mechanism of providing the rigid sample matrix for room temperature phosphorescence.…”