White organic light-emitting transistors (OLETs) are poised to be pivotal components in next generation smart displays. However, their development is hindered by the scarcity of ideal materials that concurrently exhibit high charge carrier mobility and efficient white-light emission. Herein, we present a novel molecular design strategy that achieves white electroluminescence by synergistically harnessing emissions from the monomer, excimer, and electromer within a single material. Guided by this approach, we designed and synthesized 2,6-bis(dibenzo[b,d]thiophen-3-yl)anthracene (DTA), which exhibits a photoluminescence quantum yield of 35% and a high saturation hole mobility of 5.8 cm2 V-1 s-1. Remarkably, in single-component OLET devices, DTA manifests an additional electromer emission. The combination of this red-shifted electromer band with the monomer and excimer emissions results in broad-spectrum white electroluminescence, with Commission Internationale de l'Eclairage coordinates of (0.3030, 0.3558). Moreover, the relative intensities of these three emissive species can be dynamically modulated by the gate voltage, enabling real-time tuning of the white color temperature and achieving a high color-rendering index. This work establishes a new design paradigm for high-mobility white-light emitters and represents a significant stride toward practical single-component white OLETs.

With the ongoing advancements in experimental techniques for two-dimensional conjugated polymers (2DCPs), significant reductions in disorder and the flourishing methods for structural manipulation have attracted increasing interest in their electronic structures. The tight-binding model taking molecular orbitals as the basis provides a conceptual framework for structural and functional design; however, further investigation is needed concerning the influence of secondary frontier orbitals and model construction in slipped-stacking multilayer structures. In this article, we concentrate on models for tetrahedral homopolymers, examining the role of secondary frontier orbitals through a recombined orbital basis. Results show that while a single-orbital model can give band structures that closely align with density functional theory calculations, including additional orbitals based on symmetry and phase considerations yields clearer chemical insights and facilitates straightforward extensions to multilayer systems. In particular, we emphasize a double-orbital model featuring a pair of linearly extended orbitals that cross at the center of the building block. Enhanced destructive quantum interference is observed in homopolymers compatible with this model when subjected to van der Waals interactions from an adjacent layer exhibiting a slipped stacking configuration. Through this crossed double-orbital model, the origins of the quantum interference can be effectively elucidated. Furthermore, we show that the doping-induced spin polarization in bilayers compatible with this model can be controlled by interlayer interference, a phenomenon for which our extended model provides an effective framework for analyzing.

Simultaneously balancing high mobility and ultra-low leakage current is a major challenge for metal-oxide thin-film transistors (TFTs) in ultra-low-power applications. Herein, we construct a high-performance InGaZnO/InGaO/InGaZnO tri-layer TFT based on a noncoplanar Schottky-Ohmic hybrid contact architecture. Remarkably, despite utilizing identical ITO electrodes, differential interfacial engineering explicitly decouples carrier transport: the bottom interface forms a 670 meV Schottky barrier to strictly suppress off-state leakage, while the top interface ensures low-resistance Ohmic extraction. Furthermore, a deep quantum potential well (ΔEc = 0.20 eV) formed between the high-impedance InGaZnO cladding layers and the highly conductive InGaO core strongly localizes carriers within the inner layer, constructing an ultra-low-scattering two-dimensional transport pathway. The device achieves an ultrahigh on/off current ratio exceeding 1010, together with a high field-effect mobility of 28 cm2/V s and a steep subthreshold swing of 120 mV/dec. The TFT also exhibits excellent bias stability, with a VTH shift of only 0.8 V under ± 20 V gate stress for 3600 s. Unipolar depletion-load inverters based on this architecture deliver full-swing operation and a maximum voltage gain of 55. These findings establish noncoplanar Schottky-Ohmic contacts as a powerful strategy to break the long-standing mobility-leakage trade-off, offering a scalable pathway toward low-power, high-performance oxide electronics for advanced display backplanes and large-area integrated circuits.

Developing new narrow-band display technology is crucial for next-generation high-definition displays. Organic light-emitting transistors (OLETs), which integrate dual functionalities of current amplification from organic field-effect transistor (OFET) and light emission from organic light-emitting diode (OLED) within a single device, have emerged as a promising display technology with simplified circuitry and reducing power consumption. Over the past two decades, substantial progress has been achieved in OLET device architectures, efficiencies, and multifunctional applications. In particular, new lateral area-emission OLETs, featuring a stacked OFET-OLED architecture, intrinsically form a microcavity that offers great potential for effective spectral narrowing. In this Perspective, we summarize these impressive advances in the OLET field with a specific emphasis on narrow-band-emission OLETs based on laterally stacked device geometry. We further discuss prospective strategies for simultaneously enhancing efficiency and spectral narrowing, thereby advancing OLETs toward practical high-definition, low-power display applications.

Achieving balanced ambipolar transport in organic light-emitting transistors (OLETs) is crucial for realizing high-performance electroluminescence and advancing integrated optoelectronics. However, this goal remains challenging due to the imbalanced charge injection and transport for most organic semiconductors. Encouragingly, significant effort has been made through two complementary approaches: molecular engineering to develop ambipolar high-mobility emissive semiconductors, and device architecture optimization to compensate for material limitations. The latter encompasses asymmetric electrodes, interface modification layers, multi-layer device structures, and dual-gate device structures. This review summarizes recent advances in ambipolar OLETs from both materials and device perspectives, with emphasis on the interplay between intrinsic molecular properties and extrinsic device design. Finally, we briefly discuss the persistent challenges and future prospects for achieving high-efficiency ambipolar OLETs.

Polarized emissive media are crucial for various applications in display, lighting and optical communication. An attractive research direction is to develop intrinsically white organic polarized emissive semiconductors as ideal candidates for miniaturized polarized light-emitting devices; however, it has been a considerable challenge to achieve polarized white-light emission due to the lack of suitable materials and effective preparation methods. Here we overcome this bottleneck by realizing white organic polarized emissive semiconductor single crystals (WOPESSCs). We employ a bimolecular doping method based on using highly polarized, blue-emitting 2,6-diphenylanthracene as the host single crystal, and controlling energy and polarization transfer with green- and red-emitting guests. The fabricated WOPESSCs achieve a photoluminescence quantum yield of 38.3

Two-dimensional conjugated polymers (2DCPs) have received great interest in smart devices due to their unique physical properties associated with flexibility, nanosized thickness, and correlated quantum size effect. Control of interlayer interactions of multilayer 2DCPs is crucial for modulating the confinement of charge carriers, heat, and photons to give remarkable properties because of the breaking of symmetry. However, to date, it is unclear how the multilayers of 2DCPs affect their physical properties. In this article, we for the first time perform a density functional theory calculation for the interlayer slipping effect on in-plane electronic properties of few-layer 2DCPs. Based on five homopolymers formed by C & horbar;C bonds with various stacking configurations beyond the inclined and serrated ones, results show that a moderate electric field causes the valence (conduction) band of few-layer 2DCPs to exhibit distinctive electrical characteristics which are dominated by the outermost two layers on hole (electron) enriched side. Analysis based on recombined molecular orbitals reveals that band properties are sensitive to the interlayer offsets when they result from the interference among multiple orbitals from each building block. This result provides a new guideline for manipulating charge transfer and spintronic properties of few-layer 2DCPs through an electric field to advance their various applications.

Harnessing the full potential of a gate-modulated planar junction to maximize its on-state current density presents fundamental challenges in nanotechnology, particularly for semiconducting nanowires due to their random orientations and partial coverage. Herein, we developed a straightforward method by combining dual self-alignment with nanosphere lithography to fabricate a nanomesh electrode conformally encapsulated by a polymeric insulator. This honeycomb-like nanostructured electrode is designed to form a vertically stacked electrode pair with the (semi)conducting materials precisely filling its pores. For a 200 mu m x 200 mu m transistor area, the channel width-to-length ratio is expected to approach 7.6 x 105, effectively achieving a patterning resolution of 100-200 nm without requiring expensive nanofabrication tools such as photolithography and electron-beam lithography. The resulting field-effect transistors using supramolecular poly(3-hexylthiophene) nanowires as the channel active layer exhibited a maximum on-state current density exceeding 2000 mA cm-2. Additionally, the integration of a light-emitting junction by vacuum-depositing tris(8-hydroxyquinolinato) aluminum atop results in gate-modulated uniform luminance up to 1000 cd m-2. This approach paves the way for highly integrated applications, such as micro-LED pixel driving, by maximizing the transistor current density based on a given metal-insulator-semiconductor junction.

Developing high-mobility emissive organic semiconductors (OSCs) is crucial for organic light-emitting transistors (OLETs), which belong to a type of the smallest integrated optoelectronic devices, with great potential in next-generation display technologies. Although p-type high-mobility emissive OSCs have achieved considerable progress, n-type OSC materials have rarely been reported. Herein, we designed and synthesized an n-type dibenzothiophene sulfone-based emissive organic semiconductor of DPIDBSO with photoluminescence quantum yields (PLQYs) of 30% in the solid state. Interestingly, it was found that in the DPIDBSO crystal, the growth direction was along the short axis of the molecule rather than along the pi-pi stacking direction owing to multiple weak hydrogen bonds and the presence of a crystal growth dead zone. Leveraging this "special" crystal, DPIDBSO demonstrated typical n-type transport with an electron mobility of 0.17 cm2 V-1 s-1. More importantly, DPIDBSO-based devices with only Ag electrodes showed obvious electroluminescence with an immobile emission zone in the unipolar mode. This work provides deep insights into the development of n-type OSCs with tunable optoelectronic properties through the control of the aggregation state towards high-performance OLETs.

Organic light-emitting transistors (OLETs) have attracted increasing interest as promising multifunctional three-terminal optoelectronic devices for next-generation active-matrix flat-panel displays. The development of high color rendering index (CRI) white OLETs is essential for full-color display applications demanding excellent color fidelity. However, it remains challenging with the conventional approach of doping multiple guest emitters into a host matrix, requiring precise control needed over doping concentrations. Herein, a strategy is presented to fabricate high-CRI white OLETs using ultrathin emissive layers (UEMLs). This approach enables simple fabrication and efficient exciton management through 2D energy transfer across adjacent layers. The integrated OLET architecture uniquely combines electrical switching with high-quality white light emission. The resulting devices incorporating thickness-optimized yellow and red UEMLs exhibit uniform area emission with a low turn-on voltage below 6 V and a CRI exceeding 90. These are amongst the best performance values reported to date for ultrathin non-doped electroluminescent devices. Furthermore, a 12 × 20 OLET pixel array is fabricated and employed as a planar backlight, enabling a color gamut coverage of 117% of the national television standards committee (NTSC) standard and vivid full-color image display. This work provides a promising pathway for scalable, high-quality full-color OLET displays.

Ambipolar transport is crucial for constructing high performance organic light-emitting transistors (OLETs), but the ambipolar feature is usually not exhibited due to ineffective electron injection especially in symmetric device geometry. Herein, we show that electron injection could be greatly enhanced through the judicious design of an organic interface layer of 3,7-di(2-naphthyl)dibenzothiophene S,S-dioxide (DNaDBSO) which shows an interfacial dipole effect upon contact with a metal electrode, especially an Au electrode. When incorporating a DNaDBSO film beneath Au electrodes, the electron injection and mobility were significantly enhanced in 2,6-diphenylanthracene-based OLETs, and thus ambipolar transport (μmaxh: 2.17 cm2 V-1 s-1, μmaxe: 0.053 cm2 V-1 s-1) was effortlessly obtained. Furthermore, the shift of the electroluminescent region was obviously observed upon modulation of gate voltage, which demonstrates efficient electron injection and intrinsic ambipolar transporting properties in devices. This study provides a new avenue for regulating the interface in electroluminescent devices towards high performance simple-structured OLETs in applications.

Smart agriculture is an inevitable trend in the modernization of agriculture. Achieving efficient and precise monitoring of trace pesticides is an important research direction in smart agriculture, with significant implications for a safe food supply chain. However, highly sensitive and high-throughput determination of pesticides still faces formidable challenges. Herein, we demonstrate a kind of sensitive and highly selective organophosphorus pesticide device based on organic field-effect transistors (OFETs). The unique signal amplification capability of OFETs and acetylcholinesterase modification on the active channel layer enables the achievement of accurate analysis of chlorpyrifos, parathion-methyl, and omethoate at the ppb level. Moreover, the simultaneous analysis of multiple samples is realized via the preparation of multichannel devices. Additionally, a portable monitoring applet is developed, enabling real-time assessment of the pesticide contamination status of samples based on the current response. This work provides a new avenue for constructing highly sensitive, real-time, high-flux intelligent agriculture sensing technology.

High mobility emissive organic semiconductors (HMEOSCs) are a kind of unique semiconducting material that simultaneously integrates high charge carrier mobility and strong emission features, which are not only crucial for overcoming the performance bottlenecks of current organic optoelectronic devices but also important for constructing high-density integrated devices/circuits for potential smart display technologies and electrically pumped organic lasers. However, the development of HMEOSCs is facing great challenges due to the mutually exclusive requirements of molecular structures and packing modes between high charge carrier mobility and strong solid-state emission. Encouragingly, considerable advances on HMEOSCs have been made with continuous efforts, and the successful integration of these two properties within individual organic semiconductors currently presents a promising research direction in organic electronics. Representative progress, including the molecular design of HMEOSCs, and the exploration of their applications in photoelectric conversion devices and electroluminescent devices, especially organic photovoltaic cells, organic light-emitting diodes, and organic light-emitting transistors, are summarized in a timely manner. The current challenges of developing HMEOSCs and their potential applications in other related devices including electrically pumped organic lasers, spin organic light-emitting transistors are also discussed. We hope that this perspective will boost the rapid development of HMEOSCs with a new mechanism understanding and their wide applications in different fields entering a new stage.

Narrow electroluminescence is in high demand for high-resolution displays, optical communication and medical phototherapy. Organic light-emitting transistors, as three-terminal electroluminescent devices, offer advantages in simplifying device architecture and achieving high efficiency under gate regulation. However, achieving high efficiency and narrow emission remains a challenge. Here we demonstrate that laterally integrated organic light-emitting transistors with intrinsic multiple-order microcavities can enhance efficiency and narrow emission with a universal capability for different emitters. Full-width at half-maximum values of 18 nm for red, 14 nm for green and 13 nm for blue were achieved with a maximum narrowed degree of 68%. This resulted in an impressive BT.2020 colour gamut of 97%. The peak current efficiency or blue index values for red, green and blue organic light-emitting transistors reached 26.3 cd A-1, 37.3 cd A-1 and 72.6, respectively. Moreover, organic light-emitting transistors exhibit much narrower emission and higher efficiency than equivalent, comparable devices due to their unique gate regulation capability. Our work could enable smart display technologies with high colour purity and enhanced efficiency.

Light-emitting transistors (LETs) as novel integrated optoelectronic devices demonstrate great potential applications in smart displays and visual intelligent perception. The construction of high-performance area-emission LETs with low power consumption and good reliability is urgently needed for advancing their applications, however, this integration has not been realized within a single device. Herein, we demonstrate a kind of planar-driven hybrid LET (PDHLET) that makes use of the unique advantages of high mobility and stability of inorganic and organic semiconductors in the same device. By incorporating an indium-zinc-gallium-oxide (InZnGeO) conducting layer and organic emissive layer, a high-performance stable blue-emissive PDHLET is constructed, giving a high Ion/Ioff ratio approaching 6.1 x 108 and a low Von of 5.5 V along with maximum brightness of 1264 cd/m2 as well as small VTH shift of 0.5 V after 1000 s positive stress bias. Finally, a systematic simulation, including charge concentration and Langevin recombination rate, is carried out on PDHLET for the first time, demonstrating good consistency with experimental results. This confirms the uniformity of high redistributed charge concentration in the InZnGeO conducting layer which thus enables good area emission. This study provides a new avenue for constructing high-performance stable LETs to advance various field applications.

Organic light-emitting transistors(OLETs)are miniaturized electroluminescent devices,and they simultaneously integrate the dual functionality of switching in organic field-effect transis-tors and emission in organic light-emitting diodes,which have recently aroused interest from scientists for the next-generation of display applications[1-3].Notably,white organic light-emitting transistors(WOLETs)have gained much attention for their poten-tial applications in sensors,switches,and light sources,including indoor lighting,street lighting and flood lighting[4].

Organic light-emitting transistors (OLETs) are highly integrated and minimized optoelectronic devices with significant potential superiority in smart displays and optical communications. To realize these various applications, it is urgently needed for color-tunable emission in OLETs, but remains a great challenge as a result of the difficulty for designing organic semiconductors simultaneously integrating high carrier mobility, strong solid-state emission, and the ability for potential tunable colors. Herein, a high mobility emissive excimer organic semiconductor, 2,7-di(2-anthryl)-9H-fluorene (2,7-DAF) was reasonably designed by introducing a rotatable carbon–carbon single bond connecting two anthracene groups at the 2,7-sites of fluorene, and the small torsion angles simultaneously guarantee effective conjugation and suppress fluorescence quenching. Indeed, the unique stable dimer arrangement and herringbone packing mode of 2,7-DAF single crystal enables its superior integrated optoelectronic properties with high carrier mobility of 2.16 cm 2  ⋅ V −1  ⋅ s −1 , and strong excimer emission with absolute photoluminescence quantum yield (PLQY) of 47.4 %. Furthermore, the voltage-dependent electrically induced color-tunable emission from orange to blue was also demonstrated for an individual 2,7-DAF single crystal based OLETs for the first time. This work opens the door for a new class of high mobility emissive excimer organic semiconductors, and provides a good platform for the study of color-tunable OLETs.

Fluorine-containing 2D polymer (F-2DP) film is a desired system to regulate the charge transport in organic electronics but rather rarely reports due to the limited fluorine-containing building blocks and difficulties in synthesis. Herein, a novel polar molecule with antiparallel columnar stacking is synthesized and further embedded into an F-2DP system to control over the crystallinity of F-2DP film through self-complementary π-electronic forces. The donor-accepter-accepter'-donor' (D-A-A'-D') structure regulates the charge transportation efficiently, inducing multilevel memory behavior through stepwise charge capture and transfer processes. Thus, the device exhibits ternary memory behavior with low threshold voltage (Vth1 of 1.1 V, Vth2 of 2.0 V), clearly distinguishable resistance states (1:102:104) and ternary yield (83%). Furthermore, the stepwise formation of the charge complex endows the device with a wider range to regulate the conductive state, which allows its application in brain-inspired neuromorphic computing. Modified National Institute of Standards and Technology recognition can reach an accuracy of 86%, showing great potential in neuromorphic computing applications in the post-Moore era.