Advanced materials are essential to the quality of modern day life, but the synthesis of these compounds is often inefficient in terms of energy, time and resources; especially when considering the hydrothermal batch methods used to prepare many such compounds – often requiring week-long reaction times with variable yields and product quality. In contrast, Continuous flow synthesis (CFS) provides a more readily scalable means for the efficient, effective and reproducible synthesis of inorganic compounds. This publication demonstrates the novel CFS of several metal ammonium phosphates and compare the effect of synthesis route on particle size, size distribution, and crystallinity.

Genesis of Pure Se(0) Nano- and Micro- structures in Wastewater

Nonconventional luminophores devoid of remarkable conjugates have attracted considerable attention due to their unique luminescence behaviors, updated luminescence mechanism of organics and promising applications in optoelectronic, biological and medical fields. Unlike classic luminogens consisting of molecular segments with greatly extended electron delocalization, these unorthodox luminophores generally possess nonconjugated structures based on subgroups such as ether (–O–), hydroxyl (–OH), halogens, carbonyl (CO), carboxyl (–COOH), cyano (CN), thioether (–S–), sulfoxide (SO), sulfone (OSO), phosphate, and aliphatic amine, as well as their grouped functionalities like amide, imide, anhydride and ureido. They can exhibit intriguing intrinsic luminescence, generally featuring concentration-enhanced emission, aggregation-induced emission, excitation-dependent luminescence and prevailing phosphorescence. Herein, we review the recent progress in exploring these nonconventional luminophores and discuss the current challenges and future perspectives. Notably, different mechanisms are reviewed and the clustering-triggered emission (CTE) mechanism is highlighted, which emphasizes the clustering of the above mentioned electron rich moieties and consequent electron delocalization along with conformation rigidification. The CTE mechanism seems widely applicable for diversified natural, synthetic and supramolecular systems.

Nonconventional luminophores: characteristics, advancements and perspectives.

Purely-organic clusterization‐triggered emission (CTE) has displayed promising abilities in bioimaging, chemical sensing, and multicolor luminescence. However, it remains absent in the field of circularly polarized luminescence (CPL) due to the difficulties in well-aligning the nonconventional luminogens. We report a case of CPL generated with CTE using the solid phase molecular self-assembly (SPMSA) of poly-L-lysine (PLL) and oleate ion (OL), that is, the macroscopic CPL supramolecular film self-assembled by the electrostatic complex of PLL/OL under mechanical pressure. Well-defined interface charge distribution, given by lamellar mesophases of OL ions, forces the PLL chains to fold regularly as a requirement of optimal electrostatic interactions. Further facilitated by hydrogen bonding, the through-space conjugation (TSC) of orderly aligned electron-rich O and N atoms leads to CTE-based CPL, which is capable of transferring energy to an acceptor via a Forster resonance energy transfer (FRET) process, making it possible to develop environmentally friendly and economic CPL from sustainable and renewable materials. Organic cluster-triggered emission (CTE) displays promising application in bioimaging, chemical sensing, and multicolor luminescence but circular polarize luminescence derived from CTE remains less studied. Here, the authors demonstrate CTE based CPL emission from a supramolecular film derived from solid phase molecular self-assembly.

Generating circularly polarized luminescence from clusterization-triggered emission using solid phase molecular self-assembly.

One for all and all for one, hand in hand turns the light on. Clusterization-triggered emission (CTE) is a photophysical phenomenon that has attracted increased attention in recent years. Highly efficient luminescence based on through-space conjugation (TSC) can be obtained due to the clusterization of non-conventional chromophore-forming clusteroluminogens with extended electron delocalization and a rigid conformation. The CTE process makes it possible to generate highly efficient light emitters from a vast variety of non-conjugated molecules. It is anticipated that CTE may bring about a revolution in the design of advanced functional luminescent materials in the future. In this review, we systematically summarize the current status of CTE studies, aiming at analysing the future development trends in this field. The following issues are discussed: (1) TSC hypothesis and experimental confirmation; (2) characteristics of CTE, including concentration-enhanced luminescence, excitation wavelength-dependent emission, room temperature phosphorescence (RTP) and polarization-enhanced luminescence; (3) typical examples of CTE systems, including biomacromolecules, multicolor luminescent polymers and organic–inorganic hybrid materials; and (4) applications of the CTE effect, including optical anti-counterfeiting, white LED materials, bioimaging, and molecular sensing. We envisage that the supramolecular self-assembly of CTE systems will become an important direction in the field of CTE research.

Clusterization-triggered emission (CTE): one for all, all for one

In contrast to conventional fluorescent polymers featured by large conjugation structures, a new class of fluorescent polymers without any conjugations is gaining great interest in immerging applications beyond the possibility to achieve by the conjugated polymers. Poly(ethylene glycol) (PEG), widely used in biomedical fields for a long time owing to its nontoxicity and nonimmunogenicity, is found to be fluorescence emissive in the solid state and in aqueous solution, though deemed as not fluorescent in numerous reports. Through systematic study under different conditions, the emission is ascribed to the cluster formation of its chains; thereby the blue-shift of the emission with the excitation wavelength was interpreted through the Forster resonance energy transfer. The clusterization was ascertained through size measurements, Fourier transform infrared spectroscopy, NMR analyses, and the dependence on temperature, pH, and nonsolvent presence. Tested in the presence of competitive metal ions, selective emission quenching by Fe³⁺ and Cr⁶⁺ was observed. PEG was used as a sensor for the detection of Cr⁶⁺, Fe³⁺, and H₂O₂, outperforming most of the reported sensors alike. Its uses for data encryption and cell imaging were also presented. This work provides therefore a novel face of PEG with great potential in a variety of emerging applications, in particular, as sensors in the biomedical area.

Bin Li

Papers

Fluorescence Behavior and Mechanisms of Poly(ethylene glycol) and Their Applications in Fe3+ and Cr6+ Detections, Data Encryption, and Cell Imaging

Fluorescent linear polyurea based on toluene diisocyanate: Easy preparation, broad emission and potential applications.

Aliphatic amide salt, a new type of luminogen: Characterization, emission and biological applications

Fluorescence Behavior and Emission Mechanisms of Poly(ethylene succinamide) and Its Applications in Fe^3+ Detection and Data Encryption