Ultralong organic room-temperature phosphorescence of electron-donating and commercially available host and guest molecules through efficient Förster resonance energy transfer

Abstract

Ultralong organic room-temperature phosphorescence (RTP) materials have attracted great attention recently due to its diverse application potentials. Several ultralong organic RTP materials mimicking the host-guest architecture of inorganic systems have been exploited successfully. However, complicated synthesis and high expenditure are still inevitable in these cases. Herein, we develop a series of novel host-guest organic phosphore systems, in which all chromophores are electron-rich, commercially available and halogen atom free. The maximum phosphorescence efficiency and the longest lifetime reach at 23.6% and 362 ms, respectively. Most importantly, experimental results and theoretical calculation indicate that the host molecules not only play a vital role in providing a rigid environment to suppress non-radiative decay of the guest, but also show a synergistic effect to the guest through Förster energy transfer (FERT). The commercial availability, facile preparation and unique properties also make these new host-guest materials an excellent candidate for anti-counterfeiting devices. File list (3) download file view on ChemRxiv Manuscript-20201025.docx (0.94 MiB) download file view on ChemRxiv Manuscript-20201025.pdf (770.76 KiB) download file view on ChemRxiv Supporting Information-20201025.docx (1.53 MiB)

Unity of Opposite: Highly Emissive Luminogens in both Solution and Aggregate States toward Room Temperature Phosphorescence and Electroluminescence

“…Wherein, TPA was used as a host according to previous works. 45,49 The results show that all the host-guest systems present visible afterglow when the UV light is turned off (Figure 3B and Videos S1-S3). The 1 wt% 2PB-AC/TPA, 2Me2PB-AC/TPA and 2T2PB-AC/TPA blend systems emit deep blue light with peaks at 450, 422, 447 nm, respectively (Table S2).…”

“…During the transfer process, TPA acts as an energy donor and 2PB-AC or 2Me2PB-AC or 2T2PB-AC serves as an energy acceptor. 49,[51][52] Moreover, electron spin resonance (ESR) spectra of the host-guest systems exhibit a strong signal with g-factor of 2.002 at 298 K (Figure S13). This value is close to that of a free electron (2.00232), indicative of the existence of unpaired electrons and radicals during CT process in the host-guest systems.…”

Progress on Exploring the Luminescent Properties of Organic Molecular Aggregates by Multiscale Modeling

“…Although a variety of doped organic systems with room temperature phosphorescence have been reported ( Chen et al, 2021 ; Ning et al, 2021 ; Yan et al, 2021 ), the specific configuration and molecular packing of the guest molecules in the host matrix are still unknown. For example, we recently found that pure TPA crystalline powder only exhibits weak fluorescence, while the doping TPA matrix with no more than 0.1% guest molecule (MADBA, Scheme 1 ) simultaneously shows strong fluorescence, thermally activated delayed fluorescence, and efficient room temperature phosphorescence ( Lei et al, 2021 ).…”

Time-resolved color-changing long-afterglow for security systems based on metal–organic hybrids

“…Recently, persistent room temperature phosphorescence ( p-RTP) materials (>100 ms), as one of the most fascinating species in afterglow materials, have drawn considerable interest owing to their applications in developing optical sensors, security systems, biological imaging, etc. [1][2][3][4][5][6][7][8][9][10][11][12][13] So far, tremendous efforts have been made to develop such p-RTP materials, which range from traditional inorganic 5,14 and organometallic compounds 15 to current neat organic molecules, [16][17][18][19][20][21] carbon dots, [22][23][24] host-guest architectures, [25][26][27] organic ionic compounds, 28,29 and coordination polymers (CPs)/metalorganic frameworks (MOFs). [30][31][32][33][34][35] Usually, to obtain efficient p-RTP materials, populating triplet excitons by enhancing intersystem crossing (ISC) and suppressing nonradiative dissipation are two important aspects.…”