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We report the first observation of electrogenerated chemiluminescence (ECL) from PbS quantum dots (QDs). Different ECL intensities are observed for different ligands used to passivate the QDs, which indicates that ECL is sensitive to surface chemistry, with the potential to serve as a powerful probe of surface states and charge transfer dynamics in QDs. In particular, passivation of the QD surfaces with trioctylphosphine (TOP) increases ECL intensity by 3 orders of magnitude when compared to passivation with oleic acid alone. The observed overlap of the ECL and photoluminescence spectra suggests a significant reduction of deep surface trap states from the QDs passivated with TOP.

The exploration of organic near‐infrared (NIR) luminescence, along with circularly polarized luminescence (CPL), is of vital importance due to its significance in medical and optoelectronic applications. Integrating a chiral unit into a D–A molecular structure in this research realized emission peaks at 744 nm, exhibiting a dissymmetric factor of −1.67 × 10−3. The introduced chiral TPA derivative not only imparts aggregation‐induced emission properties and CPL capabilities but also induces a redshift in the emission spectrum. Consequently, the fabricated NIR organic light‐emitting devices (OLEDs), achieve maximum electroluminescent peaks at 748 nm in nondoped devices with the external quantum efficiency of 13.7% in doped devices. This pioneering research provides inspiration for the design of NIR molecules possessing CPL properties in the future, particularly in promoting the application of intense NIR‐OLEDs. [ABSTRACT FROM AUTHOR]

The development of circularly polarized electroluminescence (CPEL) is currently hampered by the high difficulty and cost in the syntheses of suitable chiral materials and the notorious chirality diminishment issue in electrical devices. Herein, diastereomeric IrIII and RuII complexes with chiral (±)‐camphorsulfonate counteranions are readily synthesized and used as the active materials in circularly polarized light‐emitting electrochemical cells to generate promising CPELs. The addition of the chiral ionic liquid (±)‐1‐butyl‐3‐methylimidazole camphorsulfonate into the active layer significantly improves the device performance and the electroluminescence dissymmetry factors (≈10−3), in stark contrast to the very weak circularly polarized photoluminescence of the spin‐coated films of these diastereomeric complexes. Control experiments with enantiopure IrIII complexes suggest that the chiral anions play a dominant role in the electrically‐induced amplification of CPELs. [ABSTRACT FROM AUTHOR]

Crystalline materials with appealing luminescent properties are attractive materials for various optoelectronic applications. The in situ bicomponent reaction of 1,2-ethylenedisulfonic acid with 1,4-di(pyrid-2-yl)benzene, 1,4-di(pyrid-3-yl)benzene, or 1,4-di(pyrid-4-yl)benzene affords luminescent crystals with hydrogen-bonded polymeric structures. Variations in the positions of the pyridine nitrogen atoms lead to alternating polymeric structures with either a ladder- or zigzag-type of molecular arrangement. By using a nanoprecipitation method, microcrystals of these polymeric structures are prepared, showing polarized luminescence with a moderate degree of polarization. [ABSTRACT FROM AUTHOR]

Nano‐ and micromaterials with anisotropic photoluminescence and photon transport have widespread application prospects in quantum optics, optoelectronics, and displays. But the nature of the polarization information of the out‐coupled light, with respect to that of the source luminescence, has never been explored in active optical‐waveguiding organic crystals. Herein, three different modes (selective, anisotropic, and consistent) of polarized‐photon out‐coupling are proposed and successfully implemented in a set of 2D organic microcrystals with highly linearly‐polarized luminescence. It is found that the polarization direction and degree of the luminescence out‐coupled through different waveguiding channels can either be essentially retained or distinctly changed with respect to those of the original luminescence, depending on the molecular arrangement and the orientation of transition dipole moments of the crystal. This work demonstrates the promising potential of 2D emissive microcrystals in multi‐channel polarized photon transport. [ABSTRACT FROM AUTHOR]

A simple and general method is presented herein for the in situ preparations of circularly polarized luminescence (CPL)‐active microcrystals with a large luminescence dissymmetry factor glum, high fluorescence quantum efficiency (ΦFL), wide emission color tenability, and well‐ordered morphology. The reactions of pyridine‐containing achiral molecules 1–7 with chiral camphor sulfonic acid ((±)‐CSA) gave crystalline microplates formed by hydrogen bonding interactions between the protonated pyridinium units and the sulfonic anions. The chiral information of CSA are effectively transferred to the microcrystals by hydrogen bonding to afford full‐color CPL from deep‐blue to red with glum in the order of 10−2 and ΦFL up to 80 %. Moreover, organic microcrystals with high‐performance white CPL (ΦFL=46 %; |glum|=0.025) are achieved via the light‐harvesting energy transfer between blue and yellow emitters. [ABSTRACT FROM AUTHOR]

Molecular engineering has emerged as a highly interdisciplinary field of study on function‐directed molecular design, material synthesis, and property optimization, accompanied by a deep understanding of the structure‐property relationship. In this review, our recent progress on the design and preparations of photofunctional metal complexes and related materials is summarized from the perspective of coordination molecular engineering. In particular, a series of cyclometalated diruthenium complexes with near‐infrared (NIR) electrochromic property have been synthesized by engineering the bridging ligand structures. A group of ruthenium‐amine conjugated complexes with multistage NIR electrochromism are obtained on the basis of a multicenter strategy. By engineering the ligand structures, a series of new ruthenium and platinum complexes are synthesized to show switchable luminescence in response to various stimuli. In addition, photoluminescent ruthenium, iridium, and platinum complexes are assembled to afford micro/nanocrystals with well‐defined morphology and luminescent properties. What is the most favorite and original chemistry developed in your research group? Ruthenium‐triarylamine conjugated system is one of my favorite topics. How do you get into this specific field? Molecular materials with multistage redox processes and multiple near‐ infrared absorptions are a challenging task in the field of electrochromism and molecular switching. The combination of cyclometalated ruthenium complexes and triarylamines allows us to solve this issue by using a multicenter strategy with a great structural and functional diversity. What is the most important personality for scientific research? Personally, I consider honesty, curiosity, and persistence are the most important and fundamental personalities in carrying out scientific research. What's your hobbies? I enjoy playing basketball and watching basketball matches in leisure time. How do you keep balance between research and family? I like managing time by prioritizing daily tasks. If time permits, I'm glad to join family activities in cooking, walking, exercising, etc. I always appreciate and support my wife's career and my daughter's studies, from which I receive their returns in support of my career. Could you please give us some advices on improving Chinese Journal of Chemistry? Chin. J. Chem. is a classical and influential journal of chemistry. The impact of the journal keeps increasing especially in recent years. In my point of view, it would be helpful for the journal by keeping a balance among different subjects of chemistry while welcoming manuscripts on material and energy‐related interdisciplinary researches. In addition, in order to further boost its global reputation, I would like to suggest inviting more international scientists to contribute to the journal. [ABSTRACT FROM AUTHOR]

Abstract: Thermal‐responsive phosphorescent nanotubes have been fabricated from the co‐assembly of two neutral iridium complexes, which behave as the antenna chromophores and energy acceptors, respectively, in these highly ordered crystalline superstructures. By tuning the acceptor doping ratio in a range of 0 to 0.5 %, these tubes display color‐tunable phosphorescence from green to red at room temperature, and it is attributed to the highly efficient light‐harvesting and energy transfer within these materials. For the same reason, the acceptor emission in the nanotubes is amplified more than 800 times with respect to its pure non‐emissive solid sample. The doped tubes show reversible thermal‐responsiveness, in which the energy transfer was completely suppressed at 77 K and reactivated at room temperature. These processes were characterized by the in situ emission color (green, orange, and red) and spectral changes and lifetime measurements of isolated nanotubes. The temperature‐controlled exciton dynamics are responsible for the luminescent thermochromism in these crystalline materials. [ABSTRACT FROM AUTHOR]

The synthesis of π-conjugated organic materials through C–H activation and functionalization has recently received increasing attention. In this work, four pyrid-2-yl-appended para -phenylene oligomers (1 – 4) with two to five phenyl repeating units were synthesized via the Ru-catalyzed C–H activation of 2-phenylpyridine, followed by oxidative homocoupling or the arylation with a para -phenylene dibromide substrate. The single-crystal X-ray data and crystal packing of 1 and 3 are presented. In response to acid stimuli, the blue emissions of 1 – 3 are replaced by red-shifted cyan emissions, which are associated with the charge transfer transition from the phenylene backbone to the protonated pyridinium units. However, the emission of the longest congener 4 is largely quenched upon protonation. This length-dependent emission property is rationalized by DFT and TDDFT calculations. Image 1 [ABSTRACT FROM AUTHOR]