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Red and near‐infrared (NIR) organic light‐emitting diodes (OLED) have gained remarkable interest due to their numerous applications. However, the construction of highly emissive emitters is hampered by the energy‐gap law and aggregation‐caused quenching (ACQ) effect. Whereas, aggregation‐induced emission (AIE) materials could avoid the undesirable ACQ effect and emit bright light in aggregated state, which is one class of the most promising materials to fabricate high‐performance OLED with a high external quantum efficiency and low efficiency roll‐off. This review summarizes recent advances in red and NIR OLED with AIE property, including the traditional fluorescence, thermally activated delayed fluorescence, and hybridized local and charge transfer compounds. Meanwhile, the emphasis attention is paid to the molecular design principles, as well as the molecular structure‐photophysical characteristics. We also briefly further outlook the challenges and perspective of red and NIR AIE luminogens. In the field of organic light‐emitting diodes (OLED), red and near‐infrared (NIR) emitter with aggregation‐induced emission (AIE) effect can be divided into fluorescence, thermally activated delayed fluorescence (TADF), and hybridized local and charge transfer (HLCT) according to emission mechanism.

Carbon dots (CDs) have attracted significant interest as one of the most emerging photoluminescence (PL) nanomaterials. However, the realization of CDs with dominant near‐infrared (NIR) absorption/emission peaks in aqueous solution remains a great challenge. Herein, CDs with both main NIR absorption bands at 720 nm and NIR emission bands at 745 nm in an aqueous solution are fabricated for the first time by fusing large conjugated perylene derivatives under solvothermal treatment. With post‐surface engineering, the polyethyleneimine modified CDs (PEI‐CDs) exhibit enhanced PL quantum yields (PLQY) up to 8.3% and 18.8% in bovine serum albumin aqueous and DMF solutions, which is the highest PLQY of CDs in NIR region under NIR excitation. Density functional theory calculations support the strategy of fusing large conjugated perylene derivatives to achieve NIR emissions from CDs. Compared to the commercial NIR dye Indocyanine green, PEI‐CDs exhibit excellent photostability and much lower cost. Furthermore, the obtained PEI‐CDs illustrate the advantages of remarkable two‐photon NIR angiography and in vivo NIR fluorescence bioimaging. This work demonstrates a promising strategy of fusing large conjugated molecules for preparing CDs with strong NIR absorption/emission to promote their bioimaging applications. Carbon dots with both main near‐infrared (NIR) absorption and emission bands in aqueous solution are fabricated through solvothermal fusion of large conjugated perylene derivatives. After post‐surface modification with polyethyleneimine, high photoluminescence quantum yields in NIR region up to 8.3% and 18.8% are obtained in their bovine serum albumin aqueous and DMF solutions, respectively.

A chiral boron dipyrromethene (BODIPY) dye, denoted as (R)‐2, incorporating near‐infrared (NIR) emission and chiral optical behavior, is synthesized. The dye is engineered by coupling polyethylene glycol chains with R‐stereogenic centers to a donor–acceptor BODIPY core through a Suzuki coupling reaction. This modification significantly enhances the solubility and facilitates efficient chirality transfer resulting in distinct circular dichroism (CD) activity, which is quite remarkable in organic small molecule solutions. Furthermore, acid‐triggered protonation of the dye leads to a bathochromic shift in the maximum absorption wavelength (from 633 to 664 nm) and an increase in NIR emission intensity, which is attributed to the enhanced intramolecular charge transfer in solution. A novel chiral BODIPY dye, designated as (R)‐2, is synthesized, featuring near‐infrared (NIR) emission and circular dichroism activity. Incorporating polyethylene glycol chains with R‐stereogenic centers and a donor–acceptor BODIPY core, this dye remarkably improves solubility and enables efficient chirality transfer, thereby generating chiral optical behavior. Additionally, acid‐triggered protonation of the dye causes a bathochromic shift in the maximum absorption wavelength (changing from 633 to 664 nm) and an increase in NIR emission intensity.

Bioimaging with remarkable noninvasive nature, ultrahigh resolution and sensitivity allows detection of pathologies of bones, organs, and tissues. Nevertheless, the achievement of more complete information in vivo is challenged by the necessity of multiple photodetectors with diverse response ranges. Herein, a multifunctional bioimaging with Cs2AgInCl6:Yb3+ perovskites via a single InGaAs detector for superior tissue presentation is realized in this work. Co‐incorporation of foreign dopant contributes to alterations of local structural symmetry of the Cs2AgInCl6 host, disruption of parity‐forbidden transitions, and reduction in electron–phonon coupling strength, thereby boosting the near‐infrared (NIR) intensity by 40‐fold of the corresponding perovskites drastically. Moreover, an X‐ray excited NIR light output is 2.83 times that of commercial Bi4Ge3O12 scintillators. Thanks to the efficient NIR emission, the versatile perovskites film endows a multifunctional bioimaging with detailed information of biological tissue in vivo, which fundamentally offers viable avenues for promoting bioimaging technology with integrated access of tissue presentation. Currently, the acquisition of information inside living organisms is highly dependent on a variety of photodetectors with different response ranges, for which a near‐infrared‐emitting perovskite material has been designed that exhibits excellent performance under both UV and X‐ray irradiation, enabling multimodal imaging of biological tissues with only one InGaAs detector.

Phosphorescent near‐infrared (NIR) organic light‐emitting devices (OLEDs) have drawn increasing attention for their promising applications in the fields such as photodynamic therapy and night‐vision readable displays. Here, three simple phosphorescent Pt(II) complexes are synthesized, and their intermolecular interactions are investigated in crystals and neat films by X‐ray single crystal diffraction and grazing‐incidence wide‐angle X‐ray scattering, respectively. The photophysical properties, molecular aggregation (including Pt–Pt interaction), molecular packing orientation, and electron transport ability are all influenced by the strong intermolecular hydrogen bonds. Consequently, the nondoped OLEDs based on tBu‐Pt and F‐Pt show electroluminescent emissions in NIR region with the highest external quantum efficiencies of 13.9% and 16.7%, respectively. Because of enhanced molecular aggregations induced by strong intermolecular hydrogen bonds, a simple Pt(II) complex neat film shows near‐infrared (NIR) emission with high photoluminescence quantum yield, improved electron transport ability, and preferred molecular orientation. The related nondoped organic light‐emitting device (OLED) exhibits the near‐infrared (NIR) emission with a peak external quantum efficiency of 16.7%.

Intermolecular charge transfer (inter‐CT) is commonly considered to quench luminescence in molecular aggregates, especially for near‐infrared (NIR) emission. Herein, by elaborate comparison of π‐bridge effects in donor/acceptor (D/A) molecules, it is disclosed that a π‐bridge is essential in D/A molecule to involve inter‐CT in aggregates for inducing desired thermally activated delayed fluorescence (TADF) and largely suppressing non‐radiative decays, and importantly, electron‐donating π‐bridge is critical to maximize radiative decay for inter‐CT dominated emission by effective electronic coupling with bright intramolecular charge transfer (intra‐CT) for high‐efficiency NIR emission. As a proof‐of‐concept, TPATAP with thienyl as π‐bridge realized prominent photoluminescence quantum yields of 18.9% at 788 nm in solid films, and achieved record‐high maximum external quantum efficiencies of 4.53% at 785 nm in devices. These findings provide fresh insight into interplay between inter‐CT and intra‐CT in molecular aggregates and open a new avenue to attenuate the limitation of energy gap law for developing highly efficient NIR emitters and improving the luminescent efficiency of various inter‐CT systems, such as organic photovoltaic, organic long persistent luminescence, etc. Highly efficient near‐infrared emission from intermolecular charge transfer (inter‐CT) state is disclosed. In contrast to donor–acceptor type compound DPAAP with low photoluminescence quantum yields (PLQY) and inactive thermally activated delayed fluorescence (TADF), TPATAP with extended thienyl π‐bridge realized both high PLQY from inter‐CT dominated emission by effective coupling with intramolecular CT and active TADF in solid films.

Transforming carbon dots (CDs) fluorescent materials into smart materials with complex functions is a topic of great interest to nanoscience. However, designing CDs with regulating fluorescence/phosphorescence that can be visually monitored with the environment changes in real‐time remains a challenge. Here, a very simple strategy, one‐step solvent‐free catalytic assistant strategy, which is low cost, facile, environment‐friendly, and high throughput, is put forward. Hydrogen bond is used to manipulate nanostructure of CDs, and the obtained carbon dots (M‐CDs) show a series of attractive properties including matrix‐free room‐temperature phosphorescence, time‐dependent fluorescence, and near‐infrared emissive characteristics. Different from the traditional aggregation caused quenching or aggregation‐induced emission fluorescent materials, M‐CDs exhibit unprecedented and unique dispersion induced redshift fluorescence phenomenon, promoting the studies of fluorescence from static to dynamic. The causes of this phenomenon are further analyzed in detail. As a kind of intelligent fluorescent materials, this new designed CDs greatly enrich the basic recognition of CDs by illustrating the relationship between redshift fluorescence behaviors and the dispersion states, and may provide with an opportunity for solid‐state fluorescent materials, anti‐counterfeiting, cellular imaging, and hopefully many others. Illustration of simple solvent‐free catalytic assistant strategy for scalable preparation smart and versatile carbon dots (matrix‐free room‐temperature phosphorescence, time‐dependent fluorescence, and near‐infrared behaviors).

Colloidal heterostructured quantum dots (QDs) are promising candidates for next‐generation optoelectronic devices. In particular, “giant” core/shell QDs (g‐QDs) can be engineered to exhibit outstanding optical properties and high chemical/photostability for the fabrication of high‐performance optoelectronic devices. Here, the synthesis of heterostructured CuInSexS2−x (CISeS)/CdSeS/CdS g‐QDs with pyramidal shape by using a facile two‐step method is reported. The CdSeS/CdS shell is demonstrated to have a pure zinc blend phase other than typical wurtzite phase. The as‐obtained heterostructured g‐QDs exhibit near‐infrared photoluminescence (PL) emission (≈830 nm) and very long PL lifetime (in the microsecond range). The pyramidal g‐QDs exhibit a quasi‐type II band structure with spatial separation of electron–hole wave function, suggesting an efficient exciton extraction and transport, which is consistent with theoretical calculations. These heterostructured g‐QDs are used as light harvesters to fabricate a photoelectrochemical cell, exhibiting a saturated photocurrent density as high as ≈5.5 mA cm−2 and good stability under 1 sun illumination (AM 1.5 G, 100 mW cm−2). These results are an important step toward using heterostructured pyramidal g‐QDs for prospective applications in solar technologies. Colloidal heterostructured pyramidal “giant” core/shell quantum dots are developed and optical properties show near‐infrared photoluminescence (PL) emission (≈830 nm) and very long PL lifetime (in the microsecond range). The PL lifetime and simulation demonstrate their quasi‐type II band alignment and corresponding quantum dots‐sensitized photoanode exhibits a saturated photocurrent density as high as ≈5.5 mA cm−2 with good stability.

The exploration of efficient broadband portable near‐infrared (NIR) light sources is crucial for next‐generation NIR spectroscopy‐based technologies. However, developing thermally stable and highly efficient NIR photonic materials exceeding 830 nm is met with limited success. Here, a series of broadband NIR phosphors with long‐wavelength emission (λem > 830 nm) is designed by incorporating activator Cr3+ ions into ALaMgSbO6 (A = Ca, Sr) double perovskite matrices. Specifically, a cation site substitution strategy is proposed to reduce the Stokes shift of ALaMgSbO6:Cr3+ (A = Ca, Sr), rendering these as‐prepared NIR phosphors possess excellent thermal resistance performance (89.80%@423 K) and high quantum efficiency (82.5%) simultaneously. Structural analyses, DFT calculations, and spectroscopy measurements revealed that Cr3+ ions can occupy both [SbO6] and [MgO6] polyhedral sites but prefer to replace Sb5+ ions in ALaMgSbO6 (A = Ca, Sr). The luminescence efficiency and thermal stability of the samples are further improved through a flux strategy, and the emission spectra are effectively broadened by the introduction of Yb3+ as an extra NIR emitter. Furthermore, the designed phosphors exhibit a full visible‐spectrum conversion ability from 400 to 800 nm, showing great promise for versatile NIR spectroscopy applications in solar energy harvesting, night vision, non‐destructive visualization, and dental analysis. Highly efficient and thermally stable NIR photonic materials with emission over 830 nm are designed. A cation site substitution strategy is proposed to regulate the Stokes shift of the NIR emitters. The phosphors exhibit a full visible‐spectrum conversion ability from 400 to 800 nm, showing great promise for NIR spectroscopy applications in solar energy harvesting, night vision, and non‐destructive visualization.

In recent years, infrared radiation materials have received extensive attention. In this study, a kind of natural carbonate rock was highlighted and its radiation mechanism investigated, using a series of mineralogical and spectroscopy studies such as optical microscope, varying-temperature X-ray diffraction (XRD), Raman spectroscopy, X-ray fluorescence spectrometer (XRF), inductively coupled plasma mass spectrometry (ICP-MS), electron microprobe analysis (EMPA), thermogravimetry, differential thermal analysis (TG/DTA), environment scanning electron microscopy (ESEM) and infrared absorption and emission spectroscopy (IR). Results indicated that micro-nanoscale calcite (95%), graphite (3%) and pyrite (0.1%) were the primary components. Additionally, Sr 2+ and Mg 2+ were found to substitute Ca 2+ in calcite, whose content could reach 0.145% and 0.152% (wt%), respectively. On the basis of blackbody radiation theory and the radiation energy spectrum of samples from 400 to 2000 cm −1 , the average emissivity of this rock, pure calcite, pyrite and graphite was calculated as 1.007, 0.986, 0.899 and 0.488, respectively, in the temperature range of 50–140 °C. Notably, the radiation energy spectrum calculated emissivity and emission spectrum of calcite showed high consistency with the natural carbonate at all temperatures, indicating that the radiation performance of the rock was principally contributed to calcite. The heat capacity of three components presented a positive correlation with their infrared emissivity values within the temperature and wavelength of this study. The highest heat capacity of calcite benefited the enhancement of the whole thermal radiation performance of carbonate rock. The vibration of C–O bonds in the narrow absorption band of emission spectrum (1350–1500 cm −1 ) would lead to relatively high radiation energy and emissivity. In addition, the substitution of Mg 2+ and Sr 2+ for Ca 2+ improved the infrared radiation characteristics due to the 6–8% enhancement of average emissivity for pure MgCO 3 and SrCO 3 compared to CaCO 3 . This study can provide theoretical reference for infrared radiation material, using abundant and cheap natural minerals on the Earth as a source of raw materials for infrared functional materials.