Efficient, Multicolored, and Stable Room‐Temperature Phosphorescence Doped Materials Based on a Lead Halide Matrix: A Coordination‐Driven Doping Strategy

Abstract

Room temperature phosphorescence (RTP) materials have wide applications, and guest/host doping is an important method to achieve RTP. Although weak host–guest interactions (such as hydrogen bonding and π–π stacking) are considered to play a key role in inducing RTP in most doped systems (DSs), stronger and facile coordination bonds can achieve RTP more effectively and are believed to do so in DSs in related research. However, there is a lack of solid experimental evidence. Herein a new stable ligand‐modified lead halide (PCB) is synthesized and used as matrix to prepare RTP NA/PCB DSs with naphthalene derivatives (NA) as guests. Remarkably, a coordination bond between host and guest is experimentally demonstrated and revealed to play a decisive role in the generation of efficient RTP. On this basis, a coordination‐driven doping strategy is proposed to achieve efficient, multicolored, and long‐lived RTP of the DSs. In addition, NA/PCB shows excellent RTP stability and can be used in advanced security encryption, white light emitting diodes, and phosphorescent temperature sensors. This work not only proves the important role of coordination bonds in the RTP DSs, but also shows the potential of the ligand‐modified lead halide matrix as the host material of RTP.

Lead Halide Hybrids Templated by Two Coordinating Ligands for Enhanced and Stable Self-Trapped Emission

“…Since the introduction of the second 2,2′-bpy ligand substantially improved the PLQY for both the chloride and bromide materials (Table ), it is necessary to investigate the charge transfer process from the conjugated 2,2′-bpy to [Pb 6 X 10 ] 2+ layers upon photoexcitation. Firstly, from a structural perspective, pyridine is a conjugated group, and its incorporation into an organolead halide hybrid may introduce delocalized electrons to transfer from the 2,2′-bpy ligand to the soft [Pb 6 X 10 ] 4+ layer through π → π* and n → π* charge transitions. , Secondly, time-resolved PL decay at room temperature suggests a longer average lifetime (8.55 ns) of TJU-42 than that of 2,2′-bpy ligands (2.23 ns), agreeing with the charge carriers undergoing the LMCT transition (Figure d). Moreover, DFT calculations suggest the contributions of 2,2′-bpy ligands and Pb-6 s orbitals to VBM and CBM, respectively, again confirming the claim of LMCT that enhances the UV absorption and self-trapped emission (Figure h).…”

Two new Cd-based metal–organic frameworks for afterglow detection of Fe3+ and NH3

“…Our group has recently focused on the study of inorganic–organic hybrid afterglow materials. 44,45 Herein, H 2 L (H 2 L = 4-(5,7-dioxo-5,7-dihydroimidazo[4,5- f ]isoindol-6(1 H )-yl)benzoic acid) with RTP and abundant coordination sites was selected as the ligand. Through different bindings of ligands to Cd 2+ ions, [Cd(L)(DMSO) 2 ] ( 1 ) with a two-dimensional (2D) structure and [CdL(H 2 O)(DMF) 0.5 (DMSO) 0.5 ]·DMF ( 2 ) featuring an intriguing 3D interpenetrated framework with rhombus channels (∼10 × 10 Å 2 ) were successfully synthesized.…”