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<jats:title>Abstract</jats:title><jats:p>We here disclose that the incorporation of thiophene rings into a seven‐membered 8π azepine in a fused fashion produces a useful antiaromatic core for near‐infrared (NIR) dyes. In contrast to dibenzazepine derivatives with bent structures, dithieno‐fused derivatives with electron‐accepting groups adopt flat conformations in the ground state. The dithieno‐fused derivatives exhibited broad absorption spectra that cover the visible region as well as sharp emission bands in the NIR region, which are considerably red‐shifted relative to those of the dibenzo‐fused congeners. Theoretical study revealed two contradictory effects of the less‐aromatic thiophene‐fused structure, i.e., the enhancement of the antiaromaticity of the adjacent azepine ring and the relief of the antiaromaticity through the contribution of a quinoidal resonance form. The combination of the dithienoazepine core with cationic electron‐accepting groups produced a NIR fluorescent dye with an emission at 878 nm in solution.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The incorporation of insulating polymers into conjugated polymers has been widely explored as a strategy to improve mechanical properties of flexible organic electronics. However, phase separation due to the immiscibility of these polymers has limited their effectiveness. In this study, we report the discovery of multiple non‐covalent interactions that enhances the miscibility between insulating and conjugated polymers, resulting in improved mechanical properties. Specifically, we have added polyvinyl chloride (PVC) into the conjugated polymer PM6 and observed a significant increase in solution viscosity, indicative of favorable miscibility between these two polymers. This phenomenon has been rarely observed in other insulating/conjugated polymer composites. Thin films of PM6/PVC exhibit a much‐improved crack‐onset strain of 19.35 %, compared to 10.12 % for pristine PM6 films. Analysis reveal that a “cyclohexyl‐like” structure formed through dipole‐dipole interactions and hydrogen bonding between PVC and PM6 acted as a cross‐linking site in the thin films, leading to improved mechanical properties. Moreover, PM6/PVC blend films have demonstrated excellent thermal and bending stability when applied as an electron donor in organic solar cells. These findings provide new insights into non‐covalent interactions that can be utilized to enhance the properties of conjugated polymers and may have potential applications in flexible organic electronics.</jats:p>

<jats:p>Square‐planar Ni(II) complexes are interesting as cheaper and more sustainable alternatives to Pt(II) luminophores widely used in lighting and photocatalysis. We investigated the excited‐state behavior of two Ni(II) complexes, which are isostructural with two luminescent Pt(II) complexes. The initially excited singlet metal‐to‐ligand charge transfer (1MLCT) excited states in the Ni(II) complexes decay to metal‐centered (3MC) excited states within less than 1 picosecond, followed by non‐radiative relaxation of the 3MC states to the electronic ground state within 9 ‐ 21 ps. This contrasts with the population of an emissive triplet ligand‐centered (3LC) excited state upon excitation of the Pt(II) analogues. Structural distortions of the Ni(II) complexes are responsible for this discrepant behavior and lead to dark 3MC states far lower in energy than the luminescent 3LC states of Pt(II) compounds. Our findings suggest that if these structural distortions could be restricted by more rigid coordination environments and stronger ligand fields, the excited‐state relaxation in four‐coordinate Ni(II) complexes could be decelerated such that luminescent 3LC or 3MLCT excited states become accessible. These insights are relevant to make Ni(II) fit for photophysical and photochemical applications that relied on Pt(II) until now.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Metal‐based upconversion luminescence transforming high‐energy photons into low‐energy photons is an attractive anti‐Stokes shift process for fundamental research and promising applications. In this work, we developed the upconversion luminescence in co‐crystal assemblies consisting of discrete mononuclear Yb and Sm complexes. The characteristic visible emissions of Sm<jats:sup>3+</jats:sup> were observed under the excitation of absorption band of Yb<jats:sup>3+</jats:sup> at 980 nm. A series of co‐crystal assemblies were investigated based on mononuclear Yb and Sm complexes, and the strongest luminescence was obtained when the molar concentration between Yb<jats:sup>3+</jats:sup> and Sm<jats:sup>3+</jats:sup> is equivalent. The crystal structure was fully characterized by the single crystal X‐ray diffraction and upconverting energy transfer mechanisms were verified as cooperative sensitization upconversion and energy transfer upconversion. This is the first example of Sm<jats:sup>3+</jats:sup>‐based upconverting luminescence in discrete lanthanide complexes which present as co‐crystal assemblies at room temperature.</jats:p>

<jats:p>Room‐temperature phosphorescence (RTP) polymers have important applications for biological imaging, oxygen sensing, data encryption, and photodynamic therapy. Despite the many advantages polymeric materials offer such as great control over gas permeability and processing flexibility, disorder is traditionally considered as an intrinsic negative impact on the efficiency for embedded RTP luminophores, as various allowed thermal motions could quench the emitting states. However, we propose that such disorder‐enabled freedoms of microscopic motions can be beneficial for charge‐transfer‐mediated RTP, which is facilitated by molecular conformational changes among different electronic transition states. Using the “classic” pyrene‐aniline excimer as an example, we demonstrate the mutual enhancement of red/near‐infrared and green RTP emissions from the pyrene and aniline moieties, respectively, upon doping of the aniline polymer with trace pyrene derivatives. In comparison, a pyrene‐doped crystal formed with the same aniline structure exhibits only charge‐transfer fluorescence with no red or green RTP observed, suggesting that order suppresses the RTP channels. The proposed polymerization strategy may be used as a unified method to generate multi‐emissive polymeric RTP materials from a vast pool of known and unknown exciplexes and charge‐transfer complexes.</jats:p>

<jats:title>Abstract</jats:title><jats:p>CO poisoning of Pt group metal (PGM) catalysts is a chronic problem for hydrogen oxidation reaction (HOR), the anodic reaction of hydroxide exchange membrane fuel cell (HEMFC) for converting H<jats:sub>2</jats:sub> to electric energy in sustainable manner. We demonstrate here an ultrathin Ru‐based nanoflower modified with Pb (PbRuCu NF) as an active, stable, and CO‐resistant catalyst for alkaline HOR. Mechanism studies show that the presence of Pb can weaken the adsorption of *H, strengthen *OH adsorption to facilitate CO oxidation, as a result of significantly enhanced HOR activity and improved CO tolerance. Furthermore, in situ electrochemical attenuated total reflection surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRAS) suggests that Pb acts as oxygen‐rich site to regulate the behavior of the linear CO adsorption. The optimized Pb<jats:sub>1.04</jats:sub>‐Ru<jats:sub>92</jats:sub>Cu<jats:sub>8</jats:sub>/C displays a mass activity and specific activity of 1.10 A mg<jats:sub>Ru</jats:sub><jats:sup>−1</jats:sup> and 5.55 mA cm<jats:sup>−2</jats:sup>, which are ≈10 and ≈31 times higher than those of commercial Pt/C. This work provides a facile strategy for the design of Ru‐based catalyst with high activity and strong CO‐resistance for alkaline HOR, which may promote the fundamental researches on the rational design of functional catalysts.</jats:p>

<jats:p>Polycyclic aromatic hydrocarbons (PAHs) with a one‐dimensional (1D), ribbon‐like structure have the potential to serve as both model compounds for corresponding graphene nanoribbons (GNRs) and as materials for optoelectronics applications. However, synthesizing molecules of this type with extended π‐conjugation presents a significant challenge. In this study, we present a straightforward synthetic method for a series of bis‐peri‐dinaphtho‐rylene molecules, wherein the peri‐positions of perylene, quaterrylene, and hexarylene are fused with naphtho‐units. These molecules were efficiently synthesized primarily through intramolecular or intermolecular radical coupling of in situ generated organic radical species. Their structures were confirmed using X‐ray crystallographic analysis, which also revealed a slightly bent geometry due to the incorporation of a cyclopentadiene ring at the bay regions of the rylene backbones. Bond lengh analysis and theoretical calculations indicate that their electronic structures resemble pyrenacenes more than quinoidal rylenes. That is, the aromatic sextets are predominantly localized along the long axis of the skeletones. As the chain length increases, these molecules exhibit enhanced electronic absorption with a bathochromic shift, and multiple amphoteric redox waves. This study introduces a novel synthetic approach for generating 1D extended PAHs and GNRs, along with their structure‐dependent electronic properties.</jats:p>

<jats:p>Constructing chiral supramolecular assembly and exploring the underlying mechanism are of great significance in promoting the development of circularly polarized luminescence (CPL)‐active materials. Herein, we report a solvation‐mediated self‐assembly from single‐crystals to helical nanofibers based on the first protic acyclic (methoxy)(amino)carbenes (pAMACs) AuI‐enantiomers driven by a synergetic aurophilic interactions and H‐bonds. Their aggregation‐dependent thermally activated delayed fluorescence properties with high quantum yields (ΦFL) up to 95% were proved to be attributed to packing modes of Au∙∙∙Au dimers with π‐stacking or one‐dimensional extended Au∙∙∙Au chains. Via drop‐casting method, supramolecular P‐ or M‐helices were prepared. Detailed studies on the helices demonstrate that formations of extended helical Au∙∙∙Au molecular chains amplify supramolecular chirality, leading to strong CPL with high dissymmetry factor (|glum| = 0.030, ΦFL = 67%) and high CPL brightness (BCPL) of 4.87×10‐3. Our findings bring new insights into the fabrication of helical structures to improve CPL performance by modifying aurophilic interactions.</jats:p>