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The demand for high‐performance X‐ray detectors leads to material innovation for efficient photoelectric conversion and carrier transfer. However, current X‐ray detectors are often susceptible to chemical and irradiation instability, complex fabrication processes, hazardous components, and difficult compatibility. Here, we investigate a two‐dimensional (2D) material with a relatively low atomic number, Ti3C2Tx MXenes, and single crystal silicon for X‐ray detection and single‐pixel imaging (SPI). We fabricate a Ti3C2Tx MXene/Si X‐ray detector demonstrating remarkable optoelectronic performance. This detector exhibits a sensitivity of 1.2 × 107 μC Gyair−1 cm−2, a fast response speed with a rise time of 31 μs, and an incredibly low detection limit of 2.85 nGyair s−1. These superior performances are attributed to the unique charge coupling behavior under X‐ray irradiation via intrinsic polaron formation. The device remains stable even after 50 continuous hours of high‐dose X‐ray irradiation. Our device fabrication process is compatible with silicon‐based semiconductor technology. Our work suggests new directions for eco‐friendly X‐ray detectors and low‐radiation imaging system. [ABSTRACT FROM AUTHOR]

With the rapid development of high‐power electronics in aerospace, communication, and energy storage systems, the huge heat flux poses an increasing threat to the safety of electronic devices. Compared with thin films of a few micro thicknesses, high‐quality graphene thick film (GTF) exceeding hundreds of microns thickness is a promising candidate to solve thermal management challenges owing to higher heat‐flux. However, traditional GTF usually has lower thermal conductivity and weak mechanical properties attributed to disordered sheet alignment and frail interfacial adhesion. Here, a seamless bonding assembly (SBA) strategy is proposed to attain GTF over record hundreds of microns with robust coalescence interfaces. For the GTF‐SBA with ≈250 µm thickness, the in‐plane and through‐plane thermal conductivities are 925.75 and 7.03 W m−1 K−1, approximately two times and 12 times those of the GTF prepared by traditional adhesive assembly method, respectively. Furthermore, the GTF‐SBA demonstrates remarkable stability even after cycled harsh temperature shocks from 77 to 573 K, ensuring its environmental adaptability for long‐term service in extreme conditions. These findings provide valuable insights into the interfacial design of graphene bulk materials and highlight the potential applications of high‐performance graphene‐based materials for extreme thermal management demands. [ABSTRACT FROM AUTHOR]

A silicon‐integrated MXene X‐ray detector exhibits high sensitivity and an ultra‐low detection limit, enabling clear and precise single‐pixel X‐ray imaging [ABSTRACT FROM AUTHOR]

We designed a broadband lens along with a graphene/silicon photodiode for wide spectral imaging ranging from ultraviolet to near-infrared wavelengths. By using five spherical glass lenses, the broadband lens, with the modulation transfer function of 0.38 at 100 lp/mm, corrects aberrations ranging from 340 to 1700 nm. Our design also includes a broadband graphene/silicon Schottky photodiode with the highest responsivity of 0.63 A/W ranging from ultraviolet to near-infrared. By using the proposed broadband lens and the broadband graphene/silicon photodiode, several single-pixel imaging designs in ultraviolet, visible, and near-infrared wavelengths are demonstrated. Experimental results show the advantages of integrating the lens with the photodiode and the potential to realize broadband imaging with a single set of lens and a detector.