High Efficiency Emissions Research Articles

Large-eddy simulation investigation on the effects of inlet swirl/Reynolds number and fuel heating value on a turbulent kerosene spray flame

To progress toward the high efficiency and low emission aviation engine technology, it is mandatory to understand the complex phenomena including kerosene spray atomization, evaporation, turbulent mixing and combustion in the engine combustor. Nowadays with the rapid growth of computational capacity over the world, large-eddy simulation (LES) performs a more and more important role in understanding the complex multi-phase combustion process of kerosene fuels in aviation engine configuration. In the present work, LES is employed to investigate a swirling kerosene spray jet flame in a model combustor, which has been studied experimentally. The turbulent combustion is modeled by the flamelet generated manifold (FGM) approach with a 3-component surrogate kerosene skeletal mechanism. The averaged gas velocity and temperature predicted by LES generally agrees well with the experimental measurements. Local extinction is observed at the inner shear layer of the swirling spray flame, due to droplet-turbulence-flame interactions. A parametric study with 11 cases is then performed to investigate the effects of inlet swirl/Reynolds number and fuel heating value on the kerosene flame. As the swirl number increases, the enhanced turbulent mixing between kerosene fuel and air facilitates the combustion process, but combustion instabilities may occur if the swirl number is too high. A higher Reynolds number can promote the turbulent combustion via a stronger recirculation zone, but it also has strong dilution effects on the combustion field. Variations in the fuel heating value directly impact the temperature field, but the flow field, major species concentrations and droplet phase statistics are only slightly affected. These LES results give clues to achieve optimal combustion performance in realistic aviation engine configurations via better arrangements of fuel and air injections.

Precise synthesis of three-arm star polymethacrylates with high emission efficiency both in solution and in the solid state

Organic/polymeric fluorescent materials with bright emission both in solution and in the solid state have garnered growing interest in biological and optoelectronic fields. Herein, triphenylamine-derived boron ketoimine (TPA-BKI-3Br) was utilized as the initiator for atom transfer radical polymerization (ATRP) to prepare dual-state emission three-arm star polymethacrylates. Due to the intramolecular charge transfer (ICT) effect and highly distorted structure of the TPA-BKI unit, as well as the polymer arms constraining intramolecular motions, the resultant polymers displayed significant emission in solution. In the aggregated and solid states, the photophysical characteristics of the resultant polymethacrylates were notably impacted by the space charge transfer between the TPA-BKI unit and polymer chains. In addition, the TPA-BKI-based poly(2-(dimethylamino)ethyl methacrylate) (TPA-BKI-(PDMAEMA)3) exhibited fluorescence responses to temperature variations owing to the presence of dimethylamino group. This study presents an approach for the advancement of dual-state emission polymeric materials.

Effect of key structure parameters of passive pre-chamber on in-cylinder combustion processes and emissions within a gasoline engine

Due to increasingly strict global emission regulations and energy conservation policies, gasoline engines are facing significant challenges. Achieving high efficiency and ultra-low emissions in gasoline engines has become a critical technical challenge that requires attention. Pre-chamber (PC) Turbulent Jet Ignition (TJI) is a highly promising technology for improving thermal efficiency and reducing emissions in gasoline engines. This study employs a three-dimensional flow simulation analysis combined with a detailed chemical reaction mechanism. The investigation is based on eight distinct passive PC structural configurations. The effects of various structural parameters, including the orifice number (ON), orifice axis angle (OAA), orifice diameter (OD), and volume ratio (VR), on the in-cylinder combustion process and emission characteristics are investigated, in which the formation of the fire nucleus and the propagation of the flame are intensively involved. The investigation is conducted under equivalence ratio working condition. Among these, the ITE of the best configuration is relatively 5.46% higher than the baseline engine. The combustion duration decreased by 55.95% to 7.4 °CA compared to the baseline engine, while particulate soot emissions also decreased by 51.22%.

Data-driven sustainability evaluation and manufacturing system enhancement from economic, environmental, social, and sustainability perspectives.

Sustainable manufacturing is crucial to achieving carbon neutrality targets. However, research on the sustainability of manufacturing systems is limited, and high consumption, low efficiency, and high emissions have resulted in high resource consumption and rapid environmental degradation. Therefore, it is of great importance to establish an evaluation and improvement indicator system conducive to sustainable development. To this end, this study developed a data-driven methodology for evaluating and enhancing the sustainability of manufacturing systems. Manufacturing system production process data, with data dimensions unified via the emergy method, were used to construct a sustainable development evaluation model that includes four perspectives: economy, environment, society, and sustainability. The model was applied to a flange production workshop in China to analyze the interrelation mechanisms among energy consumption, resource consumption, and environmental pollution, and identify optimization schemes to improve sustainability. After implementing these optimization schemes, the emergy yield rate (EYR) of the flange increased by 23.40%, the environmental load rate (ELR) decreased by 19.03%, the per capita emergy (EPP) increased by 6.88%, and the emergy-based sustainability index (ESI) increased by 52.76%. The method presented herein offers a novel and effective tool to analyze and visualize sustainable development in manufacturing systems and identify the relationship between technology and management in the manufacturing industry; however, this method is based on historical data and rules, and lacks of flexible response to unknown situations. The results provide a reference for enterprises to achieve sustainable and lean manufacturing.

Deep red/near-infrared electro-fluorescence material with nearly 10% external quantum efficiency based on hybridized local and charge-transfer

Although the hot exciton mechanism with hybridized local and charge-transfer (HLCT) characteristics is a promising molecular design strategy, there are few organic deep red (DR) and near-infrared (NIR) HLCT-type emitters with high external quantum efficiency (EQE). Herein, this work reports three DR/NIR emitters with high EQE, TNZ-3PPOXP, TPANZPOXP, and 2PPOXNZ. These emitters show DR/NIR emission in the neat film, 664 nm for TNZ-3PPOXP, 718 nm for TPANZPOXP, and 724 nm for 2PPOXNZ. Interestingly, the emitters all possess hybridized local and charge-transfer (HLCT) characteristics and potential hot exciton channels. The corresponding non-doped OLED achieve high exciton utilization efficiency (EUE) and NIR emission, 55.6 %@694 nm for TNZ-3PPOXP, 82.8 %@736 nm for TPANZPOXP, and 42.3 %@756 nm for 2PPOXNZ. More importantly, with these emitters as the guest, PO-01 as the phosphorescent sensitizer, and CBP as the host, the sensitization device achieved nearly 10 % EQE, 9.55 %@662 nm for TNZ-3PPOXP, 4.20 %@699 nm for TPANZPOXP, and 4.49 %@702 nm for 2PPOXNZ. To our knowledge, this is one of the highest device efficiencies based on HLCT as the guest.

Numerical studies of a water-cooled premixed burner for low NOx combustion of natural gas

Natural gas, known for its high combustion efficiency and low CO2 emissions, is experiencing a significant increase in both market share and application range. Despite these advantages, there are also challenges emerged during the combustion process, including occurrence of high flame temperature, difficulty in controlling nitrogen oxide emissions, combustion instability, and a tendency to backfire. To address these issues and achieve clean and stable burning, a novel 14 MW water-cooled pre-mixed burner has been developed. In-depth simulations are conducted to assess the impact of various structural and operating parameters on combustion and pollutant emission characteristics. Results indicate that the combustion temperature follows a “W" shape with height of the low cooling component while its width governs combustion stability. Gas inlet spacing influences the flame center position and anti-backfire performance. The flare angle of gas channels determines the minimum ignition energy of the mixed gas fuel which affects ignition point and flame center position. Although large height of high cooling component contributes to low NOx emissions at the gas outlet, the resultant low temperature is undesirable for combustion stability. Further examinations of operating parameters through simulations reveal that combustion temperature initially decreases and then increases with excess air coefficient, while a significant decrease is noted with lower operating load. The premixed water-cooled technology could achieve low-NOx emissions to 2.89 mg·Nm−3 with the combustion temperature controlled at 1642K. This study provides valuable data for the design of low-NOx gas burners, serving as a reference for achieving clean and stable combustion of gas fuel.

Regional differences, source decomposition and formation mechanism of urban digital economy and energy market integration in China

The digital economy (DE) has profoundly transformed social production and life. With its characteristics of high efficiency, high productivity, and low emissions, it plays a significant role in the low-carbon transition of the energy market (EM). This study scientifically evaluates the integration level between urban digital economy and energy market (DEI) using panel data from 281 Chinese cities between 2011 and 2020. The Dagum Gini coefficient, variance decomposition, and QAP methods are employed to analyze the spatiotemporal evolution characteristics and reveal the sources and formation mechanism of integration differences. The findings are as follows: ①The integration level between China's urban digital economy and energy market exhibits an apparent upward trend, but significant differences exist among the four major regions. ②Inter-regional disparities serve as the primary spatial source of the integration differences between China's urban digital economy and energy market. ③The difference in integration efficiency is the primary structural source of the integration differences, with the western and northeastern regions experiencing the greatest impact. ④The four structural-layer factors, namely integration efficiency, integration foundation, integration structure, and integration scale, contribute positively to integration differences, with the effect intensity decreasing in sequence. Accordingly, several policy implications derive. These include implementing targeted measures to address inter-regional disparities and promote balanced integration across different region, efforts to enhance integration efficiency in underperforming regions, and prioritizing investment in infrastructure to enhance the overall integration level. In conclusion, this study provides valuable insights into the integrated development between China's urban DE and EM, offering guidance for countries seeking to optimize DE and EM.

B‒N covalent bond-involved π-extension of multiple resonance emitters enables high-performance narrowband electroluminescence.

Multi-boron-embedded multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters show promise for achieving both high color-purity emission and high exciton utilization efficiency. However, their development is often impeded by a limited synthetic scope and excessive molecular weights, which challenge material acquisition and organic light-emitting diode (OLED) fabrication by vacuum deposition. Herein, we put forward a B‒N covalent bond-involved π-extension strategy via post-functionalization of MR frameworks, leading to the generation of high-order B/N-based motifs. The structurally and electronically extended π-system not only enhances molecular rigidity to narrow emission linewidth but also promotes reverse intersystem crossing to mitigate efficiency roll-off. As illustrated examples, ultra-narrowband sky-blue emitters (full-width at half-maximum as small as 8nm in n-hexane) have been developed with multi-dimensional improvement in photophysical properties compared to their precursor emitters, which enables narrowband OLEDs with external quantum efficiencies (EQEmax) of up to 42.6%, in company with alleviated efficiency decline at high brightness, representing the best efficiency reported for single-host OLEDs. The success of these emitters highlights the effectiveness of our molecular design strategy for advanced MR-TADF emitters and confirms their extensive potential in high-performance optoelectronic devices.

Exploring the coupling mechanism between piston structure and turbulent jet ignition mode in hydrogen mixed natural gas rotary engines

The rapid development of electric vehicles has drawn extensive attention to using rotary engines as small-scale power generation devices. However, their wide application has been limited by drawbacks such as low combustion efficiency and high emissions. Therefore, to obtain rotary engines with high combustion efficiency and low emissions, this study explored the strengthening effect of natural gas/hydrogen hybrid fuel (NHHF) and Triangular Rotor Piston (TRP) structure on the combustion in the turbulent jet ignition rotary engine (TJI-RE) at different ignition advance angles (IAAs). Additionally, an experimental platform and a three-dimensional computational model for TJI-RE fueled by natural gas/hydrogen hybrid fuel (NHHF) were established in this study. The research results indicated that the TRP structure altered the combustion process by affecting the ignition area in the ignition stage and the turbulence kinetic energy during the combustion stroke. Furthermore, the SC-shaped cylinder exhibited the highest peak pressure for any fixed IAA. When the IAA was fixed at 30°CA (BTDC), the TJI-RE with the SC-shaped cylinder experienced a 12.12% increase in peak pressure and a 4.1% increase in indicated work compared to the FP-shaped cylinder. Additionally, the CO emission was reduced by 13.79%, while the NO emission showed a significant increase.

Ultra-broadband triple-peak white light-emitting carbonized polymer dots materials based on Förster resonance energy transfer

Carbonized polymer dots (CPDs) with white-light-emitting property have greatly promising application in next generation of lighting and display technologies. However, most of the reported CPD materials exhibit single peak emission and narrow emission band, resulting in difficulty to obtain white-light emission. In this work, the ultra-broadband triple-peak emission (red, green, and blue) CD-based materials with high-efficiency white light-emitting property are realized for the first time by the Förster resonance energy transfer (FRET). Blue and green emissions are derived from the fluorescence and phosphorescence of donor CPDs, while the red light is derived from receptor by FRET. Remarkably, the fabricated CPD materials show bright pure white-light emission with high overall quantum yield (QY) of 36% and the full width at half maximum of 235 nm. Besides, afterglow colors of CPD-based materials can be tuned from green to red by adjusting the ratio of donor and acceptor. Based on the high-efficiency and wide-spectrum pure white light emission characteristics of CPD-based composites, white light emitting diodes were fabricated and they exhibit bright warm white light with CIE and CCT of (0.35, 0.31) and 4041 K.

High-efficiency near-white emission of Bi3+/Sm3+ co-doped double-perovskite phosphors for optical thermometry

Near-white emission phosphors of the Bi3+/Sm3+ co-doped double-perovskite Ca2YTaO6 were successfully prepared via a simple solid-state reaction. The crystal structures and lattice parameters as functions of doping ion type and its content were analyzed. Note that all the prepared samples have the monoclinic structure with the space group of P 21/n (14). Their lattice parameters were enlarged with the increment of doping ion content since the Y3+ ion with the smaller radius was substituted by the Bi3+ and Sm3+ ions. The photoluminescence (PL) properties of single Bi3+-doped and Bi3+/Sm3+ co-doped Ca2YTaO6 phosphors were fully investigated in terms of PL emission spectrum, emission intensity, energy transfer mechanism, chromaticity coordinate, decay curve, thermal stability, and internal quantum yield. Interestingly, the Ca2YTaO6:0.015Bi3+/0.07Sm3+ phosphor exhibited a high quantum yield (70.71%). Furthermore, the relative sensitivity based on the dual-emission centers (Bi3+ and Sm3+) was also analyzed. It is demonstrated that high-efficiency near-white Ca2YTaO6:Bi3+/Sm3+ phosphor with good sensing properties is expected to be a candidate in the field of optical thermometry.

UV- and X-ray-activated broadband NIR garnet-type Ca3Ga2Sn3O12:Fe3+ phosphors with efficient persistent luminescence

Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs) are compact light sources of great interest for NIR spectroscopy applications. Beyond typical Cr3+-activated NIR-emitting phosphors, there exists a strong demand for Cr3+-free alternatives with high efficiency and broadband emission to rich the landscape of NIR luminescent materials and extend their range of application fields. Here, we report a series of Fe3+-activated Ca3Ga2Sn3O12 garnet-type phosphors exhibiting broadband NIR emission in the 650–1000 nm range attributed to 4T1(G) → 6A1(S) transition, with a maximum at 754 nm and a FWHM of 89 nm upon UV excitation. The spectroscopic results were analyzed according to the Tanabe-Sugano theory from which the crystal field parameter Dq and Racah parameters B and C were obtained for the octahedrally coordinated Fe3+ ion. Notably, the NIR persistent luminescence lasting over 1 h was detected following UV or X-ray irradiation. The possible mechanism involving electron traps was proposed to explain the observed persistent luminescence. Furthermore, a NIR pc-LED was fabricated by coating synthesized phosphor on a UV chip, and its performance was evaluated to assess its potential suitability as a NIR light source. Our discovery of novel type of nontoxic Fe3+-activated broadband NIR luminescence phosphors with efficient NIR persistent luminescence paves the way for discovering Cr3+-free multifunctional NIR luminescence materials, thereby expanding their application possibilities.

Color-tunable circularly polarized luminescence from liquid crystalline polymer networks

Chiroptical materials with circularly polarized luminescence (CPL) activities have attracted increasing interest because of their promising applications in optoelectronics, biosensing and imaging. Nevertheless, the construction of CPL-active materials with large luminescence dissymmetry (glum) factors and high emission efficiency is still challenging. Herein, a series of liquid crystalline polymer network films have been prepared by photopolymerization of cholesteric liquid-crystalline mixtures doped with aggregation-induced emission-active luminogens, TPE-TA and BDABFN. Through adjustment of the mass ratio of the two luminogens, the resultant films exhibit multicolour CPL from blue to red to white with absolute glum values up to 0.71 and fluorescence quantum yields up to 44 %. This work provides a strategy for fabricating polymeric film materials with color-tunable CPL properties and high fluorescence efficiency.

An InGaAs Vertical-Cavity Surface-Emitting Laser Emitting at 1130 nm for Silicon Photonics Application

A highly strained InGaAs quantum well (QW) vertical-cavity surface-emitting laser (VCSEL) with low threshold current density, high efficiency and output power emissions around 1130 nm was grown by MOCVD. Its static characteristics at room temperature and high operation temperature were studied in detail. The 7 μm oxide aperture device exhibits a threshold current of 0.68 mA, corresponding to a threshold current density of 1.7 kA/cm2. The slope efficiency is 0.43 W/A and the maximum output power is 3.3 mW. Continuous-wave (CW) operation in the 10–80 °C temperature range is observed. The slope efficiency is almost constant at 10–80 °C. The threshold current becomes lower at high temperatures thanks to the alignment between gain peak and cavity mode. The 3 μm oxide aperture device’s lasing in single mode with the RMS spectral width of 0.163 nm and orthogonal polarization suppression ratio (OPSR) is ~15 dB at 25 °C. The small-signal response analysis indicates that reducing the parasitics of the device and refining the fabrication process will improve the dynamics response characteristics. These results indicate that the 1130 nm GaAs-based VCSEL with highly strained InGaAs QWs is expected to be used as source for silicon photonics.

Direct Population of Triplet States for Efficient Organic Afterglow through the Intra/Intermolecular Heavy-Atom Effect.

Organic afterglow is a fascinating phenomenon with exceptional applications. However, it encounters challenges such as low intensity and efficiency, and typically requires UV-light excitation and facile intersystem crossing (ISC) due to its spin-forbidden nature. Here, we develop a novel strategy that bypasses the conventional ISC pathway by promoting singlet-triplet transition through the synergistic effects of the intra/intermolecular heavy-atom effect in aromatic crystals, enabling the direct population of triplet excited states from the ground state. The resulting materials exhibit a bright organic afterglow with a remarkably enhanced quantum efficiency of up to 5.81%, and a significantly increased organic afterglow lifetime of up to 157 microseconds under visible light. Moreover, given the high-efficiency visible-light excitable organic afterglow emission, the potential application is demonstrated in lifetime-resolved, color-encoded, and excitation wavelength-dependent pattern encryption. This work demonstrates the importance of the direct population method in enhancing the organic afterglow performance and red-shifting the excitation wavelength, and provides crucial insights for advancing organic optoelectronic technologies that involve triplet states.

Dual fluorescence induced thermally activated delayed fluorescence materials based on 2,4-Diphenylthieno[3,2-d]pyrimidine with an efficient single-molecular white electroluminescence

Dual fluorescence compounds exhibit a wide emission spectrum in visible-light range and show huge application prospect in white-light OLED (WOLED). However, few of them can realize the trade-off between high color purity of white-light emission and high emission efficiency. In this work, using sulfur atom-fused electron acceptor (A) unit 2,4-diphenylthieno[3,2-d]pyrimidine (TP) and planar electron donor (D) unit phenothiazine (PTZ), a series of novel dual fluorescence compounds with simple twisting D-A configuration were designed and synthesized, denoted as PTZ-2TP, PTZ-4TP and DPTZ-TP, respectively. Simultaneous dual fluorescence emission could be realized both solution and film state of the current system via optimizing polarization environment and doped concentration, which are attributed to the characteristic quasi-axial (QA) and quasi-equal (QE) conformations. Subsequently, these compounds were successfully applied in WOLED with high efficiency. DPTZ-TP as emitter endows the WOLED with the best device performance with greenish-white light emission, CIE coordinates of (0.33, 0.44) and high EQEmax of 11.87%, which is the highest records of such single compound systems.

A Study on the Dynamic Relationship between Embodied Carbon Productivity and Embodied Value Added in China’s Industrial Sectors: An Empirical Analysis Based on the Decoupling Model and the Panel Multinomial Logit Model

Based on the decoupling theory, this paper analyzes the relationship between the embodied carbon productivity and the embodied value added in China’s industrial sectors, evaluates the development mode of the sectors, and explores a reasonable path to promote the green and low-carbon transformation of the sectors based on the panel multinomial logit model. The empirical conclusions are as follows: (i) Except for the decrease in 2002–2005, the embodied carbon productivity achieved rapid growth in other time periods; during the period of 2002–2020, the embodied value added increased by 339.59 percentage points, with an average annual growth rate of 8.57%, and the embodied carbon productivity increased by 70.59 percentage points, with an average annual growth rate of 3.01%. (ii) As the embodied value added of the 28 industrial subsectors expanded, the changes in their embodied carbon productivity were different. This process can be roughly classified into three main phases: The first phase is the extensive growth period of 2002–2005, in which the embodied carbon productivity of most industrial subsectors declined while the embodied value added expanded; the second phase is the low-carbon transformation and development period of 2005–2012, during which the recessive positive-efficiency emission reduction became the dominant mode; and the third phase is the low-carbon development period of 2012–2020, in which the high-efficiency emission reduction became the dominant mode. (iii) When the industrial sectors are in an expansive state, increasing the substitution of capital for energy factors will make the transformation of industrial sectors more inclined to expansive high-efficiency emission reduction mode, and when the industrial sectors fall into recession, optimizing the energy structure will produce the same effect.

Exploring Efficient Dual-Phase Emissive Fluorophores with High Mobility by Integrating a Rigid Donor and Flexible Acceptor.

Developing luminogens with a high emission efficiency in both single-molecule and aggregate states, as well as high mobility, shows promise for advancing the iteration and update of organic optoelectronic materials. However, achieving a delicate balance between the plane configuration of luminophores and the strong exciton interactions of aggregates is a formidable task from the molecular design perspective. This dilemma was overcome by integrating a rigid donor and flexible acceptor to establish donor-acceptor (D-A) type emitters. The π-conjugate-extended donor ensures the substantial planarity of these molecules, allowing strong emission in solution with photoluminescence quantum yield values of 86% and 75%. Furthermore, the restricted molecular motion of the aggregation-induced emission moiety and the formation of J-aggregates reduce the quenching effect, leading to a high emissive efficiency of 85% and 91% in the aggregate state. The mildly distorted D-A geometry builds moderate electrostatic interaction, resulting in high mobility with μM,h of 7.12 × 10-5 and 3.27 × 10-4 cm2/V s. Additionally, an improved synthesized procedure for terminal E-configured acrylonitrile with metal-free and concise reaction conditions is presented. The successful application of the synthesized compounds in organic light-emitting diode devices demonstrates the practicability of the molecular design strategy with connecting a rigid donor and flexible acceptor.

Precision co-composting of multi-source organic solid wastes provide a sustainable waste management strategy with high eco-efficiency: a life cycle assessment.

With the increase of organic solid wastes (OSWs), current waste management practices, such as landfill, incineration, and windrow composting, have shown weaknesses in both resource recycling and environmental protection. Co-composting has been used to achieve nutrient and carbon recycling but is accused of high ammonia emission and low degradation efficiency. Therefore, this study developed a precision co-composting strategy (S3, which adds functional bacteria generated from food processing waste to a co-composting system) and compared it with the current OSW treatment strategy (S1) and traditional co-composting strategy (S2) from a life cycle assessment (LCA) perspective. The results showed that compared with S1, the eco-efficiency increased by 31.3% due to the higher economic profit of S2 but did not directly reduce the environmental cost. The addition of bacterial agents reduced ammonia emissions and shortened composting time, so compared with S1 and S2, the environmental cost of S3 was reduced by 37.9 and 43.6%, while the economic profit increased by 79.8 and 24.4%, respectively. The changes in environmental costs and economic benefits resulted in a huge improvement of S3's eco-efficiency, which was 189.6 and 121.7% higher than S1 and S2. Meanwhile, the adoption of S3 at a national scale in China could reduce the emission of 1,4-dichlorobenzene by 99.9% compared with S1 and increase profits by 6.58 billion USD per year. This study proposes a novel approach that exhibits high eco-efficiency in the treatment of OSWs.

White emission metal halides for flexible and transparent x-ray scintillators

Flat-panel x-ray scintillators with a high spatial resolution at a low radiation dose rate are desirable for efficient imaging applications in medical diagnostics, security inspection, and nondestructive inspection. To promote the progress of x-ray imaging technologies, it is of great interest to explore transparent scintillators with reduced light scattering, high light yields, and uniform radioluminescence. Herein, we design and prepare a novel lead-free (C12H28N)2Cu2I4 metal halide featuring a high luminescent efficiency and white emission benefiting from the double self-trapped exciton mechanism, which enable to not only match the response of semiconductor-based sensors but also enhance light yields and decrease exposed doses to objects. Furthermore, transparent, and flexible scintillators with large areas of 20.25 cm2 demonstrate an outstanding scintillation performance including a high spatial resolution of 19.8 lp mm−1 and an ultralow detection limit of 28.39 nGyair s−1, which are ∼4 times higher and 194 times lower than typical values for medical imaging, respectively. This work provides not only a new route to explore promising alternatives with broadband emission but also a novel opportunity to develop flexible x-ray imaging technology.