Excitation Light Research Articles

A modular platform for bioluminescent RNA tracking

AbstractA complete understanding of RNA biology requires methods for tracking transcripts in vivo. Common strategies rely on fluorogenic probes that are limited in sensitivity, dynamic range, and depth of interrogation, owing to their need for excitation light and tissue autofluorescence. To overcome these challenges, we report a bioluminescent platform for serial imaging of RNAs. The RNA tags are engineered to recruit light-emitting luciferase fragments (termed RNA lanterns) upon transcription. Robust photon production is observed for RNA targets both in cells and in live animals. Importantly, only a single copy of the tag is necessary for sensitive detection, in sharp contrast to fluorescent platforms requiring multiple repeats. Overall, this work provides a foundational platform for visualizing RNA dynamics from the micro to the macro scale.

Iron Oxide Clusters as Electron Donors Under Light Enhance Oxygen Reduction Kinetics at Atomically Dispersed Fe for Photocatalytic CH4 Partial Oxidation

AbstractPhotocatalytic CH4 oxidation to CH3OH emerges as a promising strategy to sustainably utilize natural gas and mitigate the greenhouse effect. However, there remains a significant challenge for the synthesis of methanol by using O2 at low temperature. Inspired by the catalytic structure in soluble methane monooxygenase (MMO) and the corresponding reaction mechanism, we prepared a biomimetic photocatalyst with the decoration of Fe2O3 nanoclusters and satellite Fe single atoms immobilized on carbon nitride. The catalyst demonstrates an excellent CH3OH productivity of 5.02 mmol ⋅ gcat−1 ⋅ h−1 with CH3OH selectivity of 98.5 %. Mechanism studies reveal that the synergy between Fe2O3 nanoclusters and Fe single atoms establishes a dual‐Fe site as MMO for O2 activation and subsequent CH4 partial oxidation. Moreover, the light excitation of Fe2O3 nanoclusters with a relative narrow band gap could deliver the electrons and protons to atomic Fe that facilitating the oxygen reduction kinetics for the robust of CH3OH synthesis.

Patterned Lead-Free Double Perovskite/Polymer Fluorescent Piezoelectric Composite Films for Advanced Anti-Counterfeiting.

The limitations of single fluorescent anti-counterfeiting technologies necessitate the development of more sophisticated encryption methods to protect information and data. Traditional optical anti-counterfeiting encryption techniques, which rely on light sources with varying wavelengths to identify information, are now insufficient to meet contemporary security demands due to their restricted response to a narrow range of wavelengths. In this study, the fabrication of patterned, lead-free double perovskite (DP)/poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) fluorescent piezoelectric composite films (CFs) is reported. These CFs integrate the up-conversion and down-conversion photoluminescent properties of Cs2Na0.8Ag0.2BiCl6:Yb3+/Er3+ DP crystals with the piezoelectric properties of P(VDF-TrFE) film, facilitating multi-modal information protection. The fluorescent signals of different concealed information in CFs are observable under the excitation of 365nm UV light and 980nm infrared (IR) light. Additionally, external pressure applied at various locations on the CFs generates corresponding electrical signals, thereby providing triple-layer encryption for protected information. A multifunctional anti-counterfeiting device has been further developed by integrating patterned optical and electrical responses onto flexible CFs, achieving synergistic protection of information security in cross fields and bringing a significant advancement to the high-level anti-counterfeiting market.

Classification and Summary of Photocatalytic Chemical Reactions Driven by Triplet‐Triplet Annihilation Upconversion

AbstractTriplet‐triplet annihilation upconversion (TTA‐UC) technology could convert low‐energy light into high‐energy light, and it is a very promising one of the upconversion technologies due to its non‐coherent excitation light, low required excitation optical power density and sensitizer/annihilator flexible adjustability. The application of TTA‐UC into photocatalysis could not only broaden the range of solar energy spectrum utilization, but also bring mild reaction conditions and higher product yields via avoiding the side reaction. However, the detailed catalytic mechanism of TTA‐UC is unclear. Therefore, in this review, we summarized and classified TTA‐UC photocatalytic chemical reactions in terms of mechanism.

Size and Surface Effects in the Ultrafast Dynamics of Strongly Cooperative Spin-Crossover Nanoparticles.

Cooperative photoinduced switching of molecular materials at the nanoscale is still in its infancy. Strongly cooperative spin-crossover nanomaterials are arguably the best prototypes of photomagnetic and volume-changing materials that can be manipulated by short pulses of light. Open questions remain regarding their non-equilibrium dynamics upon light excitation and the role of cooperative elastic interactions in nanoscale systems that are characterized by large surface/volume ratios. Femtosecond-resolved broadband spectroscopy is performed on nanorods of the strongly cooperative Fe-triazole, which undergoes a reversible low-spin to high-spin (HS) phase transition ≈360K. Supported by density functional theory and mechano-elastic Monte Carlo simulations, a marked difference is observed in the photoswitching dynamics at the surface of the nanoparticles compared with the core. Surprisingly, under low excitation (<2%) conditions, there occurs a transient increase in the HS population at the surface on the picosecond time scale, while the HS population in the core decays concomitantly. These results shed light onto the importance of surface properties and dynamical size limits of nanoscale photoresponsive nanomaterials that can be used in a broad range of applications.

Low‐Coordination Crystallographic Lattice Engineering to Discover Ce3+‐Activated Ultra‐Wide Visible‐to‐Near‐Infrared Luminescent Materials

AbstractDevelopment of ultra‐broadband visible‐to‐near‐infrared (VIS‐NIR) luminescent materials is a challenging but rewarding endeavor, as they are highly desirable for a number of applications in photonics, optoelectronics, and biological sciences. Nevertheless, to date, rare earth‐doped phosphors that can be efficiently excited by blue light and produce broadband emission in the VIS‐NIR regions remain scarce. In this study, a series of Ce3+‐doped Ba3M4O9 (M = Sc, Lu, Y) broadband luminescent materials are designed based on low‐coordination crystallographic lattice engineering. Among these materials, Ba3Y4O9:Ce3+ produces a continuous ultra‐wide VIS‐NIR emission (λem = 660 nm) in the range of 500–950 nm under 410 nm light excitation. This emission wavelength is the longest among those observed in Ce3⁺‐doped oxide materials. Structural refinement, theoretical calculation, and spectral analysis demonstrate that this VIS‐NIR broadband emission is attributed to the occupying multiple distorted octahedral lattice sites by Ce3+ in Ba3Y4O9. Several strategies are employed to enhance the luminescence intensity and thermal stability of this material, including the use of carbon paper coating, the incorporation of co‐solvents, and the addition of GeO₂ or ZrO₂. Furthermore, the as‐prepared materials demonstrate multifunctional applications in white light‐emitting diodes (WLED), night vision, and fluorescent thermometers. This study offers insights into the design of Ce3+‐doped ultra‐wide VIS‐NIR light‐emitting materials.

From Optical Fiber Communications to Bioimaging: Wavelength Division Multiplexing Technology for Simplified in vivo Large-depth NIR-IIb Fluorescence Confocal Microscopy.

Near-infrared II (NIR-II, 900-1880nm) fluorescence confocal microscopy offers high spatial resolution and extensive in vivo imaging capabilities. However, conventional confocal microscopy requires precise pinhole positioning, posing challenges due to the small size of the pinhole and invisible NIR-II fluorescence. To simplify this, a fiber optical wavelength division multiplexer (WDM) replaces dichroic mirrors and traditional pinholes for excitation and fluorescence beams, allowing NIR-IIb (1500-1700 nm) fluorescence and excitation light to be coupled into the same optical fiber. This streamlined system seamlessly integrates key components-excitation light, detector, and scanning microscopy-via optical fibers. Compared to traditional NIR-II confocal systems, the fiber optical WDM configuration offers simplicity and ease of adjustment. Notably, this simplified system successfully achieves optical sectioning imaging of mouse cerebral blood vessels up to 1000µm in depth. It can discern tiny blood vessels (diameter: 4.57µm) at 800µm depth with a signal-to-background ratio (SBR) of 5.34. Additionally, it clearly visualizes liver vessels, which are typically challenging to image, down to a depth of 300µm.

Highly Elastic Full Hydrocarbon Ultralong RTP Polymers with Visible Light Excitable S0→T1 Population

AbstractHighly elastic ultralong organic room temperature phosphorescence (RTP) polymers are highly desired in wearable optoelectronic fields, but they are hardly realized in rubbers since chain segment motions deactivate triplet excitons. In the current work, it is revealed that polystyrene (PS) can inhibit triplet thermal deactivation of coronene (Cor), and it is the serious oxygen diffusion and quenching that disables RTP emission of Cor/polymers. In view of oxygen barrier function of rubbers, PS−polyisoprene−PS tri‐block elastomers (SIS) are used as Cor's doping matrices. The results show that Cor/SIS sheets show bright and ultralong afterglow with RTP lifetime up to 3.64 s in air after brief 365 nm light excitation. More impressively, Cor/SIS and its red fluorescent dye doped sheets all exhibit ultralong room temperature afterglow under large dynamic elastic deformation. Further, all these sheets exhibit long‐wave blue light excited afterglow despite Cor/SIS having no visible light absorption band, and the unique photoexcitation and emission mechanism is verified. This work not only provides the development strategy of the latest elastic RTP materials, but also will evoke a fresh understanding on organic doped RTP polymers.

Dication Disulfuranes as Photoactivatable Sources of Radical Organocatalysts.

The recent development of photoredox and energy transfer catalysis has led to a significant expansion of visible light-driven chemical transformations. These methods have demonstrated exceptional efficiency in converting a wide range of substrates into radical intermediates and generating open-shell catalytic species. However, the simplification of catalytic systems and the direct generation of highly reactive radical organocatalysts through direct visible light irradiation from stable precatalysts remains largely an unrealized goal. This challenge is mainly due to the limited availability of precatalysts that are responsive to visible light. Herein, we introduce a new class of bench-stable dicationic disulfuranes, which release highly reactive thiyl radicals upon blue light excitation. Spectroscopic and computational studies reveal that this reactivity arises from a combination of structural features and intermolecular interactions. This family of molecules has been employed to catalyze radical cascades previously incompatible with photoredox conditions, enabling the efficient formation of 1,2-dioxolanes and 1,3-hydroxyketones in excellent yields and short reaction times.

Dication Disulfuranes as Photoactivatable Sources of Radical Organocatalysts

The recent development of photoredox and energy transfer catalysis has led to a significant expansion of visible light‐driven chemical transformations. These methods have demonstrated exceptional efficiency in converting a wide range of substrates into radical intermediates and generating open‐shell catalytic species. However, the simplification of catalytic systems and the direct generation of highly reactive radical organocatalysts through direct visible light irradiation from stable precatalysts remains largely an unrealized goal. This challenge is mainly due to the limited availability of precatalysts that are responsive to visible light. Herein, we introduce a new class of bench‐stable dicationic disulfuranes, which release highly reactive thiyl radicals upon blue light excitation. Spectroscopic and computational studies reveal that this reactivity arises from a combination of structural features and intermolecular interactions. This family of molecules has been employed to catalyze radical cascades previously incompatible with photoredox conditions, enabling the efficient formation of 1,2‐dioxolanes and 1,3‐hydroxyketones in excellent yields and short reaction times.

Photoinduced Electrochemiluminescence Immunoassays.

Optimization of electrochemiluminescence (ECL) immunoassays is highly beneficial for enhancing clinical diagnostics. A major challenge is the improvement of the operation conditions required for the bead-based immunoassays using the typical [Ru(bpy)3]2+/tri-n-propylamine (TPrA) system. In this study, we report a heterogeneous immunoassay based on near-infrared photoinduced ECL, which facilitates the imaging and quantitative analysis of [Ru(bpy)3]2+-modified immunobeads at low anodic potential. The photovoltage generated by the photoanode under near-infrared light promotes oxidation processes at the electrode/electrolyte interface, thus considerably lowering the onset potential for both TPrA oxidation and ECL emission. The anti-Stokes shift between the excitation light (invisible to the human eyes) and the visible emitted light results in a clear and stable signal from the immunobeads. In addition, it offers the possibility of site-selective photoexcitation of the ECL process. This approach not only meets the performance of traditional ECL immunoassays in accuracy but also offers the additional benefits of lower potential requirements and enhanced stability, providing a new perspective for the optimization of commercial immunoassays.

Thermally stable Al4B2O9:Ce3+ nanofibers with intense blue emission and Al4B2O9:Ce3+/Dy3+ nanofibers with color-tunable luminescence and white-light emission via energy transfer

Dy3+ can achieve white-light emission at the appropriate intensity ratio of yellow to blue light in specific hosts due to its wide yellow and blue emitting bands. However, luminescence intensity of singly doped Dy3+ in the matrix is low, which limits its application in PC-WLEDs. Al4B2O9 has become a promising rare earth ion-doped matrix owing to its ease of doping, low price, excellent chemical and thermal stability. In this work, to improve the Dy3+ emission intensity and to achieve color-tunable luminescence and white-light emission, with the help of energy level matching engineering, Ce3+ ions with a strong and broad absorption band and suitable energy levels matching with Dy3+ are selected as high-efficient sensitizers. Ce3+ doped and Ce3+/Dy3+ co-doped one-dimensional (1D) Al4B2O9 nanofibers are designed and successfully synthesized using a simple electrospinning coupled with an oxidative calcination. Under the excitation of 286-nm UV light, Al4B2O9:Ce3+ nanofibers emit intense blue light and can be used as blue-emitting phosphor, and the emission peak of Al4B2O9:Ce3+/Dy3+ nanofibers at 374 nm is attributed to the 5d→2F5/2 energy level transition of Ce3+, and emission peaks at 483 and 575 nm are ascribed to the 4F9/2→6H15/2, 13/2 energy level transitions of Dy3+, respectively. By modulating the doping concentration of Dy3+ and Ce3+→Dy3+ energy transfer (ET) process, color-tunable luminescence and white-light emission are resoundingly realized to address the weak luminescence intensity of Dy3+. In addition, Al4B2O9:Ce3+/Dy3+ nanofibers have excellent thermal stability. The formation mechanism and luminescence mechanism of Al4B2O9:Ce3+/Dy3+ nanofibers are presented, and the Ce3+→Dy3+ ET mechanism in Al4B2O9:Ce3+/Dy3+ nanofibers is elucidated. The designing concept and the technology in this work are instructive for preparing new phosphors with 1D morphology and super fluorescence.

Preparation and scintillation properties of Eu3+-doped high crystallinity tellurite glass ceramics

In this study, a high-crystallinity glass-ceramic scintillator doped with Eu³⁺ containing Bi₂Te₄O₁₁ nanocrystals was prepared using a traditional melt crystallization method. The optimal heat treatment conditions, phase structure, and luminescent properties of the glass-ceramics were systematically investigated using various characterization techniques, including DSC, XRD, SEM, and spectrophotometry. To achieve glass-ceramic samples with high transmittance and excellent luminescent performance, the optimal heat treatment process was determined to be 500 °C for 10 minutes. The final sample was found to have a density of 5.9 g/cm³ and a crystallinity of 70%. Strong orange-red light emission was exhibited by the glass-ceramic under both 465 nm light and X-ray excitation. The maximum integral X-ray excited luminescence (XEL) intensity was found to reach 20.2% of that of the commercial Bi4Ge3O12 (BGO) scintillation crystal. It is indicated by the research that Eu³⁺-doped high-crystallinity tellurate glass-ceramics are promising candidate materials for scintillators in the field of X-ray detection.

Dual-functional ratiometric fluorescence sensor based on silica spheres for highly selective detection of Hg2+ and Fe3+

Ratiometric fluorescence sensors, which validate the absence of ambient and excitation light intensity effects, have attracted significant attention. In this study, a novel nanohybrid dual-emission system was fabricated by combining nitrogen-doped carbon quantum dots (NCQDs) with 8-hydroxyquinoline (8-HQ). This system allows for the simultaneous detection of Fe3+ and Hg2+ ions by utilizing distinct signals. A ternary hollow structure nanosensor containing core-shell silica spheres modified by 8-HQ molecules and decorated with carbon quantum dots was fabricated by subsequent solvothermal synthesis. The designed nanohybrid emits dual-emission fluorescence peaks at 480 and 340nm, originating from the intrinsic structure of NCQDs and 8-hydroxyquinoline, respectively. When Hg2+ is present, only the fluorescence intensity at 480nm is noticeably reduced. However, in the presence of Fe3+ ions, the fluorescence intensity at 480nm remains mostly unchanged, but clear fluorescence quenching is detected at 340nm. There was a linear relationship between fluorescence intensity ratios at 340 and 480nm and the concentration of Hg2+ and Fe3+, with detection limits of 9.50nM and 0.96μM, respectively. Furthermore, it demonstrated satisfactory assay performance in quantifying the mercury content in amalgam alloy and the Fe3+ concentration in a water sample. The results of this study offer a new approach to designing multifunctional fluorescent sensors and a potential application for biomedicine and environmental monitoring.

Microwave enhanced carbon dots synthesis from eggshell membrane: Versatile applications in heavy metal ion sensing, strain free detection of fingerprints, UV shielding, food packing and anti-counterfeiting

In this study, a one-step microwave irradiation process combined with a sodium hydroxide (NaOH) solution allowed for the quick and easy synthesis of carbon dots (CDs) from eggshell membrane (ESM) ashes. The resultant CDs demonstrated exceptional selectivity for Fe3+ and excellent fluorescence (FL) with a quantum yield (QY) of 15.3%. Utilizing synthetic CDs, a sensitive nanoprobe is utilized to identify free Fe3+ within the 0-350μM (R2 = 0.9976) range, with a 0.281μM limit of detection (LoD). Additionally, the CDs were shown to be useful for intracellular Fe3+ detection applications because of their low cytotoxicity and biocompatibility. Investigations using real samples at 420 and 500nm excitation wavelengths showed promising results in terms of real-world application. In order to transform molecular data into FL signal outputs, a multi-input logic gate is also constructed. In the UV-A (93%), UV-B (88%), UV-C (98%) and HEBL (79%) regions, blue colour-emitting CDs had the maximum UV blockage, but pure polyvinyl alcohol (PVA) absorbed less than 22–30% of the light in all UV regions. The integration of CDs into the polymer improved the thermal characteristics of the PVA film. Additionally, testing of in vitro cell viability demonstrated that the CDs, when embedded in the PVA, did not cause cytotoxicity to the Neuroblastoma cell line (SH-SY-5Y). As a paradigm for perishable commodities, the effects of CDs and PVA were assessed on the shelf life of tomatoes. When fresh tomatoes were coated with CDs@PVA and PVA, weight and moisture loss were effectively decreased, according to the results of the long-term monitoring study. Throughout almost 34 days at room temperature, it also dramatically reduced the growth of fungi and prevented spoiling, all the while maintaining the fruits original colour and appearance. The CDs FL under 365nm UV light excitation makes them well-suited for creating fluorescent inks to deter counterfeiting. Additionally, the study explored the CDs exceptional FL properties for use as a luminescent fingerprint powder, aiding in the detection of latent fingerprints (LFPs) on various surfaces. The findings from this study highlight the potential of cost-effective and safe CDs for a range of applications, including non-cytotoxic UV blocking, active packaging, Fe3+ sensing, fingerprint detection, anti-counterfeiting (AC) measures and flexible nanocomposite (NC) films.

Multicolor luminescence and high efficient optical thermometric performance of Eu3+ and Sm3+ in self-activated Na2LuMg2V3O12 garnet

To develop efficient luminescence and optical thermometry materials for color display and non-contact temperature measurement, novel RE3+ (RE = Eu, Sm) doped self-activated Na2LuMg2V3O12 phosphors were prepared by a typical solid-state reaction method. Their crystal structure, morphology, multi-color luminescence and temperature sensing properties were elaborately investigated. Under UV light excitation, an intense and broad green-yellow emission band from VO43– group is observed in the Na2LuMg2V3O12 matrix, indicating its potential application in solid state lighting. After the incorporation of Eu3+ and Sm3+ ions, efficient energy transfer (ET) from VO43– group to Eu3+/Sm3+ ions occurs and the emission color of the samples can be readily tuned among different color ranges. Besides, based on the change of luminescence intensity and lifetimes of VO43– group in Na2LuMg2V3O12:Eu3+ and Na2LuMg2V3O12:Sm3+, the ET efficiency was analyzed and the mechanism is illustrated. Finally, large discrepancy between the thermal stability of VO43– group and Eu3+/Sm3+ ions are observed in the temperature-dependent emission spectra of Na2LuMg2V3O12:Eu3+ and Na2LuMg2V3O12:Sm3+. By taking advantage of the luminescence intensity ratio (LIR) between VO43– group and Eu3+/Sm3+ ions in Na2LuMg2V3O12:0.01Eu3+ and Na2LuMg2V3O12:0.07Sm3+, two new types of optical thermometry mediums were designed and their basic temperature sensing parameters were calculated.

Near-field probing of surface plasmon polariton formation in imprinted gold nanoisland arrays

Large-area imprinting stamps with nanometer-scale features are a rapidly developing area of research in plasmonics. In integrated photonic structures, surface plasmon (SPs) and surface plasmon polaritons (SPPs) are tuned by selecting both the appropriate wavelength and the angle of incidence of the excitation light. The resulting exponential fields can be studied by an optical technique such as scanning near-field optical microscopy (SNOM). Here, we report on the application of the aperture-type SNOM technique to characterize, at nanoscopic and microscopic scales, the formation of the SPPs and the beat pattern formed with the superposition of SPs and the effective component of the probing light formed in discrete metallic nanostructures of Au fabricated on imprinting stamps. We discuss a model to describe the beat pattern in terms of this superposition and demonstrate that the dominant SPs have a transverse nature. Our experiments are supported by modeling the optical response and near-field in gold nanostructures using the simulation tool Tidy3D. Our results provide a straightforward way to investigate and characterize SPPs at the nanostructure level.

Face-to-Face Gold Porphyrins.

The interaction of square-planar metal complexes through space is of fundamental interest and relevant for the potential cooperative catalysis of two metal complex sites. In order to elucidate gold/gold, gold/porphyrin, and porphyrin/porphyrin interactions in the formal oxidation states +III and +II (after reduction) and in the excited triplet state after light excitation, a Pacman bis(gold(III)) complex [Au2(DPD)][PF6]2 with square-planar face-to-face gold(porphyrin) moieties has been prepared and characterized. Absorption and luminescence spectroscopy, cyclic voltammetry, and EPR spectroscopy on [Au2(DPD)]n+ and a mononuclear reference are complemented by DFT and TDDFT calculations.

Identification of peripheral nerve functional fascicles in Sprague-Dawley rats by the carbon quantum dot-Annexin V antibody complex

To explore a method to identify the sensory and motor fascicles of the peripheral nerve to achieve accurate peripheral nerve functional fascicle suture. The peripheral nerve Sunderland V injury model, muscle branch of the femoral nerve and saphenous nerve were established in the bilateral femoral nerves of Sprague-Dawley (SD) rats. The specific samples were grouped as follows: the main trunk of the femoral nerve was exposed bilaterally and cut with microscopic scissors in the main trunk of the femoral nerve to prepare a model of Sunderland V injury in the mixed fascicle of peripheral nerves; the muscle branch of the femoral nerve was exposed bilaterally and cut in the middle section of the muscle branch of the femoral nerve to prepare a model of Sunderland V injury in the motor fascicle of peripheral nerves; the saphenous nerve was exposed bilaterally and cut at 1 cm below the patella to prepare a model of Sunderland V injury to the sensory fascicle of the peripheral nerves. A carbon quantum dot (CD)-annexin V antibody complex was prepared and applied to the distal and proximal nerve stumps of the peripheral nerve Sunderland V injury model groups of SD rats. Under the excitation light source of a 380 nm uv lamp, fluorescence color development was observed under a fluorescence microscope after 5, 10, 15, and 20 min. At 5 min, sections of the bilateral femoral nerve trunk, muscular branches of the femoral nerve, and Sunderland V lesion of the saphenous nerve in SD rats were only dark in color under the microscope, and there was no difference in fluorescence. The intensity of the staining increased significantly for 10–20 min. The sensory fascicles and saphenous nerves of the femoral nerve trunk showed blue fluorescence under the CD-Annexin V antibody complex staining, while the motor fascicles and muscle branches of the femoral nerve trunk showed no fluorescence. Fluorescence intensity gradually decreased after 20 min of staining. There was no significant difference in the staining intensity at 5, 10, 15, and 20 min in each group. Our results suggest that the CD-Annexin antibody complex can be used to identify functional fascicles of peripheral nerves in SD rats.

Advancing Two-Photon Photodynamic Therapy Over NIR-II Excitable Conjugated Microporous Polymer with NIR-I Emission.

The availability of second near-infrared (NIR-II) excitable two-photon photosensitizers with NIR-I emission for efficient photodynamic therapy (PDT) is limited by challenges in molecular design. In this study, a NIR-II light-excitable two-photon conjugated microporous polymer (Tph-Dbd) with emission in the NIR-I region is developed. The large conjugated system and delocalized electronic structures endow Tph-Dbd with a large two-photon absorption cross-section under NIR-II light excitation. Moreover, the efficient electron acceptor and donor units within the π-conjugated backbones result in NIR-I emission for high signal-to-background ratio imaging, as well as separated highest occupied molecular orbitaland lowest unoccupied molecular orbital distributions for excellent singlet oxygen generation ability. The excellent NIR-II excitable two-photon absorption activity, NIR-I emission, good biocompatibility, and high photostability allow Tph-Dbd to be used for efficient in vitro fluorescence imaging guided PDT. Moreover, the impressive photothermal effect of Tph-Dbd can overcome the limitations of PDT in the treatment of hypoxic tumors. This study highlights a strategy for designing NIR-II excitable two-photon photosensitizers for advanced PDT.