In this study, we present a broadband nano-photodetector based on single-layer graphene (SLG)-carbon nanotube thin film (CNTF) Schottky junction. It was found that the as-fabricated device exhibited obvious sensitivity to a wide range of illumination, with peak sensitivity at 600 and 920 nm. In addition, the SLG-CNTF device had a fast response speed (τr = 68 μs, τf = 78 μs) and good reproducibility in a wide range of switching frequencies (50–5400 Hz). The on-off ratio, responsivity, and detectivity of the device were estimated to be 1 × 102, 209 mAW−1 and 4.87 × 1010 cm Hz1/2 W−1, respectively. What is more, other device parameters including linear performance θ and linear dynamic range (LDR) were calculated to be 0.99 and 58.8 dB, respectively, which were relatively better than other carbon nanotube based devices. The totality of the above study signifies that the present SLG-CNTF Schottky junction broadband nano-photodetector may have promising application in future nano-optoelectronic devices and systems.

In this study, a high‐performance photodetector comprised of formamidinium cesium lead iodide (FA1−xCsxPbI3) thin film is developed. The Cs‐doped FAPbI3 perovskite material is synthesized through a simple spin‐coating method, via which FA1−xCsxPbI3 with different Cs doping levels (x = 0.1, 0.15, 0.2, and 0.3) can be obtained. Further optoelectronic characterization reveals that the FA0.85Cs0.15PbI3 photodetector exhibits reproducible sensitivity to irradiation with wavelengths in the range from 240 to 750 nm, whereas it is weakly sensitive to wavelengths longer than 750 nm. The responsivity and specific detectivity are estimated to be around 5.7 A W−1 and 2.7 × 1013 cm Hz1/2 W–1, respectively. It is also worth noting that the present perovskite photodetector demonstrates an ultrafast response speed (tr/tf: 45 ns/91 ns) at zero bias voltage, which is probably related to the ultrafast lifetime and high quality of thin film according to the Hall effect study. Finally, this device shows a weak degradation in sensitivity to white light after storage at ambient condition for 45 days. The totality of the broadband sensitivity, high specific detectivity, ultrafast response speed, and self‐driven property renders the FA1−xCsxPbI3 an idea material for high‐performance photodetectors application.

Recently, near‐infrared light photodetectors (NIRPDs) have attracted increasing interest due to their promising applications in both military and civil purposes. One‐dimensional inorganic semiconductor nanostructures (NSs) have unique electrical and optical properties and have been widely used to fabricate many NIRPDs. These prototype devices have geometries ranging from photoconductive‐type photodetectors and metal–semiconductor Schottky junction photodetectors to nano‐heterojunction photodetectors. They have good device performance including high responsivity and specific detectivity, fast response speed, low power consumption, etc. Here, we will review the state‐of‐the‐art advance in the fabrication of 1D semiconductor NSs for NIRPD application. We first briefly survey recent progress in the growth and fabrication methodologies including both bottom‐up and top‐down approaches. We also highlight the achievement in this flourishing field by sketching device fabrication, comparing the device performance, and discussing the operation mechanism. Finally, we close with unresolved issues and challenges.

A high-performance red light nano-photodetector was constructed by modifying a multi-layer graphene (MLG)–CdSe nanoribbon Schottky junction with hexagonal copper nanoparticles with localized surface plasmon resonance (LSPR).