Min Sang Kwon

Herein we report a rational design strategy for tailoring intermolecular interactions to enhance room-temperature phosphorescence from purely organic materials in amorphous matrices at ambient conditions. The built-in strong halogen and hydrogen bonding between the newly developed phosphor G1 and the poly(vinyl alcohol) (PVA) matrix efficiently suppresses vibrational dissipation and thus enables bright room-temperature phosphorescence (RTP) with quantum yields reaching 24%. Furthermore, we found

Metal-free organic phosphorescent materials are attractive alternatives to the predominantly used organometallic phosphors but are generally dimmer and are relatively rare, as, without heavy-metal atoms, spin-orbit coupling is less efficient and phosphorescence usually cannot compete with radiationless relaxation processes. Here we present a general design rule and a method to effectively reduce radiationless transitions and hence greatly enhance phosphorescence efficiency of metal-free organic

In this review, we provide a brief history, progress, and applications, and discuss the remaining challenges of photocontrolled reversible addition-fragmentation chain transfer (RAFT) polymerization (<i>i.e.</i>, photoinduced electron/energy transfer-RAFT (PET-RAFT), photoiniferter, and photomediated cationic RAFT polymerization). Among these, visible-light-driven RAFT polymerization has attracted particular attention in recent years due to its benefits, including low energy consumption and the

A lot of efforts have been made for the development of novel organic photoredox catalysts (PCs) due to their gratifying replacement for conventional transition metal‐based PCs in photoredox catalysis. In this minireview, we summarized and classified the recently reported organic PCs into several categories based on functional groups (e.g. cyanoarene, phenazine, xanthene, and others) with their applications to various organic transformations including polymerization reactions. The strategies used

Abstract Herein we report a rational design strategy for tailoring intermolecular interactions to enhance room‐temperature phosphorescence from purely organic materials in amorphous matrices at ambient conditions. The built‐in strong halogen and hydrogen bonding between the newly developed phosphor G1 and the poly(vinyl alcohol) (PVA) matrix efficiently suppresses vibrational dissipation and thus enables bright room‐temperature phosphorescence (RTP) with quantum yields reaching 24 %. Furthermore

A highly efficient organic photocatalyst (OPC) for photoinduced electron/energy-transfer reversible addition–fragmentation chain-transfer (PET-RAFT) polymerization was identified through a systematic catalyst design and discovery. The devised OPC offers excellent control over PET-RAFT polymerizations of methyl methacrylate at very low catalyst loadings (5 ppm), that is, ca. 5–50 times lower loadings than other OPCs reported so far. Moreover, excellent oxygen tolerance was achieved using the disc

We report herein a new class of piezochromic luminescence (PCL) material with an acid stimulus response based on a donor (D)–acceptor (A)–donor (D) molecular triad, m-BHHDCS (1), synthesized via a rational design strategy. Acid-responsive harmane derivatives were rationally introduced into the unique D–A–D platform to obtain dual-stimuli responsive properties, i.e. acidochromic and piezochromic behaviors. Upon exposure to mechanical force and/or acid treatment, the pristine powders of 1 showed r

Current technological advances in the organic light-emitting diode panel design of foldable smartphones demand advanced adhesives with UV-blocking abilities, beyond their conventional roles of bonding objects and relieving deformation stress. However, optically clear adhesives (OCAs) with UV-blocking ability cannot be prepared using conventional UV-curing methods relying on a photoinitiator. Herein, a new acrylic resin that can be efficiently cured using visible light without oxygen removal is p

The unique 16-membered macrolide (+)-exiguolide (1) was the target of a total synthesis featuring radical and Prins cyclizations of β-alkoxyacrylates, along with ring-closing olefin metathesis. The structure incorporates two cis-2,6-disubstituted oxane rings where one of the rings has an exocyclic enoate group. The successful synthesis of 1, isolated from a marine sponge, led to the unambiguous determination of its absolute stereochemistry. Supporting information for this article is available on

Metal-free organic phosphors can be an attractive smart optical sensing materials since, in such compounds, intersystem crossing (ISC) and the phosphorescence process are placed in subtle competition with fluorescence, internal conversion (IC), and non-radiative decay pathways. Here, we report a unique environment-dependent multi-luminescence switching behavior of metal-free organic phosphorescent materials. Through combined photophysical measurements and computational electronic structure analy

Since the pioneering discovery of a protein bound to poly(ethylene glycol), the utility of protein-polymer conjugates (PPCs) is rapidly expanding to currently emerging applications. Photoinduced energy/electron-transfer reversible addition-fragmentation chain-transfer (PET-RAFT) polymerization is a very promising method to prepare structurally well-defined PPCs, as it eliminates high-cost and time-consuming deoxygenation processes due to its oxygen tolerance. However, the oxygen-tolerance behavi

Abstract The highly sensitive optical detection of oxygen including dissolved oxygen (DO) is of great interest in various applications. We devised a novel room‐temperature‐phosphorescence (RTP)‐based oxygen detection platform by constructing core–shell nanoparticles with water‐soluble polymethyloxazoline shells and oxygen‐permeable polystyrene cores crosslinked with metal‐free purely organic phosphors. The resulting nanoparticles show a very high sensitivity for DO with a limit of detection (LOD

Thermoplastic polyurethane (TPU) is an essential class of materials for demanding applications, from soft robotics and electronics to medical devices and batteries. However, traditional TPU development is primarily relied on specific soft segments, such as polyether, polyester, and polycarbonate polyols. Here, a novel method is introduced for developing TPU elastomers with enhanced performance and superior functionalities compared to conventional TPUs, achieved through the use of α,ω-hydroxyl en

Current research on organic light emitters which utilize multiple resonance-induced thermally activated delayed fluorescence (MR-TADF) materials is gaining significant interest because of the materials' ability to efficiently generate color-pure blue emission. However, the underlying reasons for high color purity remain unclear. It is shown here that these emitters share a common electronic basis, which is deduced from resonance structure considerations following Clar's rule, and which is termed

This review highlights advancements in the synthesis, characterization, and applications of ladder-like polysilsesquioxane (LPSQ). Emphasizing its double-stranded structure, and superior properties, it shows LPSQ's role in hybrid materials.