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The praseodymium-doped indium zinc oxide (PrIZO) thin-film transistor (TFT) is promising for applications in flat-panel displays, due to its high carrier mobility and stability. Nevertheless, there are few studies on the mechanism of annealing on PrIZO films and the fabrication of flexible devices. In this work, we first optimized the annealing-process parameters on the glass substrate. As the annealing temperature rises, the film tends to be denser and obtains a lower surface roughness, a narrower optical-band gap and less oxygen-vacancy content. However, the μ-PCD test shows the 250 °C-annealed film obtains the least defects. And the PrIZO TFT annealed at 250 °C exhibited a desired performance with a saturation mobility (μsat) of 14.26 cm2·V−1·s−1, a subthreshold swing (SS) of 0.14 V·dec−1, an interface trap density (Dit) of 3.17 × 1011, an Ion/Ioff ratio of 1.83 × 108 and a threshold voltage (Vth) of −1.15 V. The flexible devices were prepared using the optimized parameters on the Polyimide (PI) substrate and subjected to static bending tests. After bending at a radius of 5 mm, the mobility of devices decreases slightly from 12.48 to 10.87 cm2·V−1·s−1, demonstrating the great potential of PrIZO for flexible displays. [ABSTRACT FROM AUTHOR]

In recent years, 2D/3D heterojunction electronic devices have attracted considerable attention. As the size decreases, enhancing the speed of MOSFETs, reducing the subthreshold swing (SS), and lowering the power consumption (P) have become challenging. Therefore, in the post‐Moore era, in response to the continuation of Moore's law, junction field‐effect transistors (JFETs) based on mixed‐dimensional MoS2/GaN heterojunctions are proposed via thickness engineering. Accordingly, flat hetero interface and large potential barrier height of 5 eV across the heterojunction, an ultra‐low SS of 60.9 mV dec−1 (The Boltzmann limit is 60 mV dec−1) is achieved at Vds = 0.1 V when the MoS2 thickness is 10 nm. Additionally, a high Ion/Ioff ratio of 107 and a saturation current density (Jds) of 0.16 µA µm−1 is achieved. As the thickness of MoS2 increased from 6 to 16 nm, the working mode transitioned from enhancement mode to depletion mode. The depletion region across the channel is verified using computer‐aided design technology. Finally, an N‐type load inverter with a maximum voltage gain of 4 and a minimum static P of 25 nW is applied. Overall, the work provides a universal strategy for constructing a series of high‐performance transition metal dichalcogenide/GaN JFETs. [ABSTRACT FROM AUTHOR]

2D van der Waals (vdWs) heterojunctions exhibit facile fabrication process and tunable optoelectronic properties. However, suppressing interfacial charge traps and multifunctional photoresponse remain significant challenges. Here, the study designs a 2D multifunctional phototransistor based on ambipolar MoTe2/graphene (Gr)/p‐type SnS0.25Se0.75 double vdWs vertical heterostructure via alloy engineering. The middle Gr interlayer is pivotal in reducing interfacial charge traps, facilitating vertical photocarrier transportation, and enhancing light absorption coefficient. Under photogating effect, the trapped electrons in SnS0.25Se0.75 promote the photogating effect, resulting in the maximum photogain of 8084 and specific detectivity (D*) of 8.2 × 1012 Jones. Under photoconductive effect, a high responsivity (R) of 36.9 A W−1 and D* of 7.17 × 1011 Jones are achieved. Under photovoltaic effect, the devices exhibit a remarkable R of 501 mA W−1, D* of 1.4 × 1011 Jones. Notably, a self‐driven photocurrent polarized ratio of 8 under 635 nm is achieved because of the anisotropic nature of SnS0.25Se0.75 and the effective double built‐in electric fields. By varying the gate voltage, the polarization ratio can be modulated from 1 to 2.5, enabling reconfigurable polarized‐sensitive detection. Above all, the designed heterojunction with multifunctional and reconfigurable polarization detection. [ABSTRACT FROM AUTHOR]

The limited yield of H2 production has posed a significant challenge in contemporary research. To address this issue, researchers have turned to the application of surface plasmon resonance (SPR) materials in photocatalytic H2 generation. SPR, arising from collective electron oscillations, enhances light absorption and facilitates efficient separation and transfer of electron‐hole pairs in semiconductor systems, thereby boosting photocatalytic H2 production efficiency. However, existing reviews predominantly focus on SPR noble metals, neglecting non‐noble metals and SPR semiconductors. In this review, we begin by elucidating five different SPR mechanisms, covering hot electron injection, electric field enhancement, light scattering, plasmon‐induced resonant energy transfer, and photo‐thermionic effect, by which SPR enhances photocatalytic activity. Subsequently, a comprehensive overview follows, detailing the application of SPR materials‐metals, non‐noble metals, and SPR semiconductors‐in photocatalytic H2 production. Additionally, a personal perspective is offered on developing highly efficient SPR‐based photocatalysis systems for solar‐to‐H2 conversion in the future. This review aims to guide the development of next‐gen SPR‐based materials for advancing solar‐to‐fuel conversion. [ABSTRACT FROM AUTHOR]

The determination of band gaps in unidentified materials has substantial importance for photovoltaic applications. In this research we used machine learning techniques to predict the band gap of perovskite materials within an acceptable margin of error. We developed a model to predict the band gaps of inorganic perovskites using machine learning algorithms. Our methodology utilizes a comprehensive dataset of 3720 ABX3-type perovskites and 2660 A2B(I)B(II)X6-type double perovskites, encompassing key properties such as band gap and formation energy. The features include nearly 300 descriptors generated by Matminer python. We applied six machine learning models, including XGBoost. The most effective model, XGBoost, demonstrated a notable R2 coefficient of 0.873 and a root mean square error (RMSE) of 0.5868 eV. Lastly, we conducted SHAP (SHapley Additive exPlanation) analysis to identify the most influential descriptors. The findings indicate that a higher formation energy, a significant proportion of transition metals, and a large number of d orbital valence electrons contribute to the formation of narrow bandgap perovskites. Conversely, a substantial number of f-orbital electrons and electronegativity differences between elements tend to result in wide-bandgap perovskites. This comprehensive analysis not only offers insights into the fundamental factors influencing the band gap of perovskite materials but also underscores the potential of machine learning in expediting materials research. [ABSTRACT FROM AUTHOR]

As the competition intensifies in enhancing the integration and performance of integrated circuits, in accordance with the famous Moore's Law, higher performance and smaller size requirements are imposed on the dielectric layers in electronic devices. Compared to vacuum methods, the production cost of preparing dielectric layers via solution methods is lower, and the preparation cycle is shorter. This paper utilizes a low-temperature self-exothermic reaction based on the solution method to prepare high-performance Al2O3 dielectric thin films that are compatible with flexible substrates. In this paper, we first established two non-self-exothermic systems: one with pure aluminum nitrate and one with pure aluminum acetylacetonate. Additionally, we set up one self-exothermic system where aluminum nitrate and aluminum acetylacetonate were mixed in a 1:1 ratio. Tests revealed that the leakage current density and dielectric constant of the self-exothermic system devices were significantly optimized compared to the two non-self-exothermic system devices, indicating that the self-exothermic reaction can effectively improve the quality of the dielectric film. This paper further established two self-exothermic systems with aluminum nitrate and aluminum acetylacetonate mixed in 2:1 and 1:2 ratios, respectively, for comparison. The results indicate that as the proportion of aluminum nitrate increases, the overall dielectric performance of the devices improves. The best overall performance occurs when aluminum nitrate and aluminum acetylacetonate are mixed in a ratio of 2:1: The film surface is smooth without cracks; the surface roughness is 0.747 ± 0.045 nm; the visible light transmittance reaches up to 98%; on the basis of this film, MIM devices were fabricated, with tested leakage current density as low as 1.08 × 10−8 A/cm2 @1 MV and a relative dielectric constant as high as 8.61 ± 0.06, demonstrating excellent electrical performance. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterostructures, formed by stacking different two‐dimensional (2D) materials, have emerged as a promising platform for next‐generation optoelectronic devices through band engineering. While various all‐2D and mixed‐dimensional heterojunction phototransistors based on p–n junctions or Schottky junctions have been developed, their performance, often constrained by the trade‐off between responsivity (R) and response speed, limits their widespread application. Here, a dual‐mode phototransistor based on a MoTe2/WS2/WSe2 double vdW heterostructure is designed. The bottom WSe2 layer effectively modulates the entire MoTe2/WS2 heterojunction channel, enabling both photoconductive and photovoltaic modes with exceptional optoelectronic properties in a single device. Specifically, the proposed device exhibits a maximum R of 2540 A W−1 and an impressive specific detectivity of 8 × 1012 Jones under the photoconductive mode. Under the photovoltaic mode, it achieves a fast response speed of 35.3/49.1 µs and a high light on/off ratio of 2 × 105. Additionally, the device exhibits latent potential for high‐resolution imaging across various wavelengths and fast optical communication. This work offers a rational alternative for achieving dual‐mode photodetection and highlights its promising application prospects in imaging and optical communication. [ABSTRACT FROM AUTHOR]

With the development of the information industry, the wearable three‐dimensional (3D) near‐eye display that can provide complete visual information has attracted increasing attention. Compared with other existing 3D display technologies, the holographic display is a promising true 3D display technology that can fully record and reproduce the original 3D scenes. The ability to present a continuous parallax and depth perception gives holography technology an unprecedented promise in the next‐generation 3D near‐eye display. However, currently available holographic near‐eye display systems can only provide a limited viewing area (including the field of view and eyebox), greatly restricting its practical application. Focusing on the development requirements of large viewing‐area 3D holographic near‐eye display, the reasons are introduced first why the viewing area of current holographic displays is limited and then the existing solutions from different aspects, including multiplexing‐based methods, steering viewing window methods, aperiodic wavefront modulation methods, and some emerging holographic display technologies are summarized. These various solutions are analyzed respectively, and their representative works are investigated. In addition, the different applications of holography in the near‐eye display system are also discussed. Finally, the advantages and disadvantages of these techniques are compared and perspectives are given. [ABSTRACT FROM AUTHOR]