Recent Progress in Pure Organic Room Temperature Phosphorescence of Small Molecular Host–Guest Systems

Abstract

Figure 2. Steroid based host matrix in realizing RTP emission. (a) Chemical structures of steroid host and second amino-substituted deuterated carbon as well as the design principle in realizing the RTP emission. Reproduced with permission. 39 Copyright 2013, Wiley. (b) Chemical structures of host 4, guest 3, and dispersant 5 as well as the application in thermal reversible recording materials. Reproduced with permission. 40 Copyright 2013, Wiley. (K r = phosphorescent decay rate, K q = rate of quenching long-lived triplet excitons).

Boosting purely organic room-temperature phosphorescence performance through a host–guest strategy

“…Besides, by dispersing trace amounts of the guest molecules into the host matrix, the host can dilute the guest emitters as a solid solvent, thus avoiding the concentration quenching effect caused by aggregation. 36,55 However, considering the low doping ratio of the guests in host-guest system, it is much difficult to obtain a precise cocrystal structure through traditional single crystal XRD technology, limiting its further investigation. Herein, to gain a deeper understanding on the underlying mechanism and provide a solid theoretical support for the role of host often discussed, a MD calculation was conducted to simulate the aggregation structure of host-guest system.…”

“…Recently, a number of favourable host materials have been developed, including macrocyclic compounds, 32 polymer matrices, [33][34][35] and co-crystallized organic small molecular host. [36][37][38][39] Among them, host-guest cocrystal matrix has been carefully studied because its powerful crystalline lattice can protect the guest from quenched species such as water, oxygen and other nonradiative factors. 15,40 Despite the progress made in host-guest chemistry, the investigation of specific clustered structure still encounters many obstacles for the lack of cocrystal structure, especially when the guest content is very low.…”

Red-Emissive Organic Room-Temperature Phosphorescence Material for Time-Resolved Luminescence Bioimaging

“…24 The host matrix not only provides a rigid environment to restrict movement, but also serves as a bridge to facilitate ISC between singlet and triplet of guest. 24,[44][45][46][47][48][49] Herein, we propose a strategy to achieve highly efficient red phosphorescence emission via the combination of molecular engineering and host-guest system (Scheme 1). Two methylene groups were introduced into 1,2,5-triphenyl-1H-pyrrole (TPPy) to lock the molecular conformation and extend its conjugation (Scheme 1a).…”

A metal-free 2D layered organic ammonium halide framework realizing full-color persistent room-temperature phosphorescence

“…9,16 The second is to create a rigid oxygen-free environment, inhibit the movement of organic luminophore, and reduce the probability of non-radiative deactivation of triplet excitons. 17,18 Among them, the internal heavy atom effect produced by directly introducing halogen atoms into the luminescent group is one of the most effective methods to increase the rate of ISC and improve the phosphorescence efficiency. 19,20 However, the internal heavy-atom effect (HAE) also accelerates the phosphorescence process, reducing the phosphorescence lifetime (τ).…”