Near-Infrared Phosphorescence Emission of Binuclear Mn(II) Based Metal-Organic Framework for Efficient Photoelectric Conversion

Abstract

The development of metal-organic framework (MOF) based room-temperature phosphorescence (RTP) materials has raised extensive concern owing to their widespread applications in the field of anti-counterfeiting, photovoltaics, photocatalytic reactions, and bio-imaging. Herein, one new binuclear Mn(II) based 3D MOF [Mn 2 (L)(BMIB)·(H 2 O)] ( 1 ) (H 5 L = 3,5-bis(3,5-dicarboxylphenxoy) benzoic acid, BMIB = tran-4-bis(2-methylimidazolyl)butylene) has been synthesized by a facile hydrothermal process. In 1 , the protonated BMIB cations show infinite π-stacking arrangement, residing in the channels of the 3D network extended by L ligand and binuclear Mn(II) units. The orderly and uniform host-guest system at molecular level emits intense white light fluorescence and long-lived near infrared phosphorescence under ambient conditions. These photophysical processes were well-studied by density functional theory (DFT) calculations. Photoelectron measurements reveal high photoelectron response behavior and incident photon-to-current efficiency (IPCE).

Metal-Organic Frameworks With Variable Valence Metal-Photoactive Components: Emerging Platform for Volatile Organic Compounds Photocatalytic Degradation

“…Moreover, the Fe 3 -μ 3 -oxo cluster can directly absorb the visible-light and initiate an electron-hole separation event. Photo-induced electron and hole migrate separately to the catalyst surface to react with the adsorbed O 2 and H 2 O molecules, yielding strongly oxidative ROS species such as O 2 (Hao et al, 2020;Li et al, 2020b;Zhang et al, 2020b). 1) The organic linkers with huge diversity in MOFs usually serve as antennas for light harvesting.…”

“…Every as-prepared MOF photocatalyst example commented in Ti-Based MOFs Photocatalysts for Degradation of Indoor Air VOCs and Other Metal-Based MOFs Photocatalysts for Degradation of Indoor Air VOCs section is now summarized in Table 1 . More importantly, the latest preparation and modification strategies of MOFs-based photocatalysts are emerging, mainly for overcoming the inherent disadvantages in degradation of VOC pollutants ( Hao et al, 2020 ; Li et al, 2020b ; Zhang et al, 2020b ). 1) The organic linkers with huge diversity in MOFs usually serve as antennas for light harvesting.…”

Photo-functionalized metal–organic frameworks for anti-counterfeiting applications

“…24 Meanwhile, when the electrons transition to triple excited states, they show phosphorescence when they transition back to the ground states. 25 The third type of fluorescence comes from fluorescent guests, which can be grafted into the skeleton by embedding, encapsulation, ion exchange or ligand modification. 26,27 Effective combinations of fluorescent sources have been used to construct PMOFs, which have been universally applied to fluorescence regulation, chemical sensing and optical anti-counterfeiting.…”

A reversible room temperature phosphorescence/delayed fluorescence switch trigged by solvent exchange in a Ca-based coordination polymer

“…[19][20][21] However, most of the RTP properties are caused by the framework itself, [26][27][28][29][30][31] and the RTP properties caused by the guest molecules/ions themselves or RTP switching caused by guest changes are rare. [32][33][34] Considering the porous properties of many CPs, 31,35,36 it is undoubtedly of great significance to study the latter for the development of new sensor and switch materials.…”