Nontraditional Organic/Polymeric Luminogens with Red‐Shifted Fluorescence Emissions

Abstract

Nontraditional organic/polymeric luminogens, which do not contain any conventional chromophores like large 𝝅-conjugated benzene rings and/or heterocycles, have attracted rapidly growing attention owing to their importance in the fundamental understanding of photoluminescence mechanisms and potential practical applications. However, compared to traditional luminogens, most nontraditional luminogens (NTLs) emit fluorescence in the blue region, and only very limited NTLs with green, yellow, and red emissions have been reported. It is of great scientific and practical importance to develop NTLs with red-shifted emissions and understand their mechanisms. This review first provides a brief overview of the types of NTLs based on heteroatoms in them, the luminescence mechanism and luminescent characteristics of NTLs, then summarizes recent progress in NTLs with red-shifted emissions and the main strategies employed, i.e., introducing multiple nonconventional chromophores, introducing intra-/intermolecular interactions to rigidify clusters, and introducing electron-giving/withdrawing groups into molecules to lower the gap between the HOMO-LUMO energy levels. This review also provides the perspectives and outlook on future development of NTLs with red-shifted emissions.

Hydrogen Bonding-Induced Oxygen Clusters and Long-Lived Room Temperature Phosphorescence from Amorphous Polylols

“…The pure white PMO powder showed distinct excitation-dependent photoluminescence (PL) properties (Figure 2a), similar to many of CL chromophores reported before. [13,26] The spectrum covered an emission band from 350 to 600 nm, with an emission peak of 438 nm excited by 360 nm (Figure 2a). The fluorescence lifetime measured at the emission peak of 438 nm was 3.95 ns (Figure 2b).…”

Ultrafast Self-Healing, Highly Stretchable, Adhesive, and Transparent Hydrogel by Polymer Cluster Enhanced Double Networks for Both Strain Sensors and Environmental Remediation Application

“…The luminescence originated from the TSC of n−π and π−π interactions of C�O and −NH of ohPEI. 31,32,41 After evaporation, the xerogel could be used to easily form robust films with a higher fluorescence intensity (7.6-fold that of the hydrogels, λ em = 521 nm), indicating the AIE properties. Meanwhile, a 43 nm blue shift was observed for the film.…”

Hydrogen-Bonding-Induced Clusteroluminescence and UCST-Type Thermoresponsiveness of Nonconjugated Copolymers

“…Stimuli-responsive light-emitting polymers (SRLEPs) are a type of intelligent material that can change the intensity or wavelength upon external stimuli. − These polymers have attracted great attention due to their promising applications in the fields of information displaying and biosensing. − Nonconventional luminescent polymers are an emerging type of light-emitting polymer. − These polymers are devoid of large π conjugated groups and possess structural designability, improved water solubility, and better biocompatibility, − rendering themselves as excellent candidates for the design of SRLEPs. − In this case, the correlation between the stimuli responsiveness and the luminescent behavior has become a key scientific question.…”

“…The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.macromol.2c01531. Institution State Key Laboratory Base of Novel Functional Materials and Preparation Science, Ningbo Key Laboratory of Specialty Polymers, School of Materials Science & Chemical Engineering, Ningbo University, Ningbo 315211, China Pengbo Han − State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology, Guangzhou 510640, China Shunfeng Yu − Institution State Key Laboratory Base of Novel Functional Materials and Preparation Science, Ningbo Key Laboratory of Specialty Polymers, School of Materials Science & Chemical Engineering, Ningbo University, Ningbo 315211, China Xinjun Wu − Institution State Key Laboratory Base of Novel Functional Materials and Preparation Science, Ningbo Key Laboratory of Specialty Polymers, School of Materials Science & Chemical Engineering, Ningbo University, Ningbo 315211, China Yueyi Tian − Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China Qianhan Liu − Institution State Key Laboratory Base of Novel Functional Materials and Preparation Science, Ningbo Key Laboratory of Specialty Polymers, School of Materials Science & Chemical Engineering, Ningbo University, Ningbo 315211, China Jinhui Wang − Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China; orcid.org/0000-0001-7024-3313 Mingming Zhang − Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China; orcid.org/0000-0001-8286-6198 This work was funded by the National Natural Science Foundation of China (22075154 and 21604044) and the CAMS Innovation Fund for Medical Sciences (2021-I2M-1-058).…”