Vertical SnO₂ based p‐n junctions are pivotal since they built the core components in photoelectronic systems. Nevertheless, preparation of high‐quality p‐SnO₂ with controllable hole mobility and concentration is still a great challenge owing to the self‐compensating effect and lattice distortion caused by the radius discrepancy between host and doped atoms. Herein, p type GaN:Mg grown by metal organic chemical vapor deposition is employed as hole transportation layer to construct p‐n heterojunction with intrinsic n‐SnO₂ prepared by atomic layer deposition. Both material preparation techniques are compatible with current industrial mass production processes. The p‐GaN/n‐SnO₂ heterojunction can be developed as solar cell, dual‐color light emitting diode and self‐powered, high speed ultraviolet (UV) photodetector with external quantum efficiency of 74% at 0 V bias voltage. In addition, direct recombination of donor bound excitons (D⁰X) and UV emission red shifts caused by quantum confinement Stack effect are observed in SnO₂. Since our device fabrication technique is a standard craft in photoelectronics, the study of p‐GaN/n‐SnO₂ heterojunction suggests a simple and effective strategy for large scale device integration in next generation high performance photoelectronic devices. image

A stable all-inorganic CsPbBr₃/GaN heterojunction photodetector operated in both photoconductive mode and depletion mode is fabricated, exhibiting a sensitive response to the radiation from the near UV to the green band.

In this work, we have reported a vertical CsPbBr₃/ZnO heterojunction photodetector for photo-sensing lights from UV to visible band. The ZnO thin film is deposited on the c-sapphire substrate through a molecular beam epitaxy (MBE) technique, and then the CsPbBr₃ thin film is synthesized on the as-prepared ZnO film layer by using a solution processing method. The as-prepared CsPbBr₃/ZnO heterostructure presents type-II energy band structure induced by the energy band offset effect, which can promote the separation and extraction efficiencies of the photo-generated electron-hole pairs. Compared with the CsPbBr₃ based metal-semiconductor-metal (MSM) structure photodetector, the heterojunction photodetector presents higher responsivity and detectivity of 630 µA/W and 7 × 10⁹ Jones. While compared with the ZnO based MSM structure photodetector, the heterojunction device reveals much faster response speeds of 61 µs (rise time) and 1.4 ms (decay time). These findings demonstrate that the CsPbBr₃/ZnO heterojunction photodetector is promising for constructing next generation perovskite based optoelectronic devices.

In this work, a UV photodetector was fabricated by constructing a heterojunction between β phase GaO_xN_y prepared by atomic layer deposition and p-GaN prepared by metal organic chemical vapor deposition. The p-GaN layer shows an extremely sharp absorption characteristic with a cutoff edge of ∼365 nm, while β-GaO_xN_y shows a broad absorption behavior in the UV region due to its low crystal quality grown at low temperature (200 °C). The β-GaO_xN_y/GaN photodetector exhibits an obvious rectifying characteristic due to the formation of the type-II heterojunction and shows a high responsivity of 1.46 A/W at a bias voltage of −5 V and a rapid response speed (a rise time of 3.3 ms and a decay time of 6.8 ms). The investigation of the β-GaO_xN_y/GaN photodetector suggests a simple and effective strategy for next-generation high-performance optoelectronic devices.

We propose a novel strategy to introduce platinum into the metal nodes of ZIF-8 by preloading Pt as a dopant in ZnO (Pt–ZnO) and then convert it to Pt doped ZIF-8 (Pt-ZIF-8) through a chemical vapor deposition (CVD) approach. The solvent-free conversion of Pt–ZnO to Pt-ZIF-8 allows the Pt dopant in ZnO to coordinate with organic linkers directly without the formation of Pt nanoparticles, which is a general issue of many methods. This general synthesis strategy may facilitate the discovery of MMOFs that have not been reported previously.

A facile and low-cost strategy to fabricate CsPbBr₃ single crystals is essential for developing perovskite optoelectronic devices. Herein, we have presented a room temperature anti-solvent precipitate method for growing sub-centimeter-sized CsPbBr₃ single crystals. The as-prepared CsPbBr₃ single crystal has an orthorhombic structure, and phase transition occurs as the measured temperature increases. The as-grown CsPbBr₃ single crystal also shows abundant surface morphologies including footsteps, precipitated crystals, cracks, and pits. Subsequently, a metal–semiconductor–metal (MSM)-structured photodetector was fabricated based on the CsPbBr₃ single crystal. Under 525 nm green light illumination, the photodetector exhibits an obvious response and the photocurrent linearly increases with the increase in the light intensity. The rise time of the photodetector increases from 0.82 s to 2.19 s as the light intensity is enhanced from 15 mW/cm² to 160 mW/cm², indicating that more time is required to reach to a stable photocurrent. However, the decay time is as fast as ~0.82 ms, irrelevant of the light intensity. The photocurrent, under continuous light illumination, was further studied and this indicates that a stronger light intensity can accelerate the attenuation of the device.