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The highly ordered film assembled by regularly 1D nanostructures has potential prospects in electronic, photoelectronic and other fields because of its excellent light‐trapping effect and electronic transport property. However, the controlled growth of highly ordered film remains a great challenge. Herein, large‐area and highly ordered Bi2S3 film is synthesized on fluorophlogopite mica substrate by chemical vapor deposition method. The Bi2S3 film features hollowed‐out crosslinked network structure, assembled by 1D nanobelts that regularly distribute in three orientations, which agrees well with the first principles calculations. Based on the as‐grown Bi2S3 film, the broadband photodetector with a response range from 365 to 940 nm is fabricated, exhibiting a maximum responsivity up to 98.51 mA W–1, specific detectivity of 2.03 × 1010 Jones and fast response time of 35.19 ms. The stable instantaneous on/off behavior for 500 cycles and reliable photoresponse characteristics of the Bi2S3 photodetector after storage in air for 6 months confirm its excellent long‐term stability and air stability. Significantly, as sensing pixel and signal receiving terminal, the device successfully achieves high‐resolution imaging of characters of "H", "I" and "T", and secure transmission of confidential information. This work shows a great potential of the large‐area and highly ordered Bi2S3 film toward the development of future multiple functional photoelectronic applications. [ABSTRACT FROM AUTHOR]

In this work, efficient two‐color (blue and yellow) hybrid white organic light‐emitting diodes (WOLEDs) with high efficiencies are constructed by introducing iridium(III) bis(4,6‐(difluorophenyl) pyridinato‐N,C2')picolinate (FIrpic) as electron sensitizer. Experimental results demonstrate that FIrpic with the deep lowest unoccupied molecular orbital (LUMO) level enables preferential electron trapping to collect excessive electrons, thus realizing carrier's balance and high recombination probability. The obtained cool WOLED exhibits the maximum external quantum efficiency (EQE), current efficiency (ηc), and power efficiency (ηp) of 31.05%, 76.36 cd A−1 and 69.92 lm W−1, respectively. Moreover, by gradient doping FIrpic into yellow EML, the generated forward built‐in electric field originating from gradient electrons distribution reduces carriers transport resistance and improves the transport of holes; the diffusion effect of gradient electrons distribution promotes electrons' transport, thus enhancing the utilization probabilities of carriers and excitons. Besides, FIrpic acts also as an energy transfer ladder to facilitate the energy transfer from host to yellow emitter. Consequently, warm WOLED with enhanced yellow emission achieves the maximum EQE, ηc, and ηp of 33.27%, 75.66 cd A−1 and 88.04 lm W−1, respectively. [ABSTRACT FROM AUTHOR]

Photodetectors have a wide range of applications across various fields. Self-powered photodetectors that do not require external energy have garnered significant attention. The photoelectrochemical type of photodetector is a self-powered device that is both simple to fabricate and offers high performance. However, developing photoelectrochemical photodetectors with superior quality and performance remains a significant challenge. The electrolyte, which is a key component in these detectors, must maintain extensive contact with the semiconductor without degrading its material quality and efficiently catalyze the redox reactions of photogenerated electrons and holes, while also facilitating rapid charge carrier transport. In this study, α -Ga2O3 nanorod arrays were synthesized via a cost-effective hydrothermal method to achieve a self-powered solar-blind photodetector. The impacts of different electrolytes—Na2SO4, NaOH, and Na2CO3—on the photodetector was investigated. Ultimately, a self-powered photodetector with Na2SO4 as the electrolyte demonstrated a stable photoresponse, with the maximum responsivity of 0.2 mA/W at 262 nm with the light intensity of 3.0 mW/cm2, and it exhibited rise and decay times of 0.16 s and 0.10 s, respectively. The α -Ga2O3 nanorod arrays and Na2SO4 electrolyte provided a rapid pathway for the transport of photogenerated carriers and the built-in electric field at the semiconductor–liquid heterojunction interface, which was largely responsible for the effective separation of photogenerated electron–hole pairs that provided the outstanding performance of our photodetector. [ABSTRACT FROM AUTHOR]

All‐inorganic metal halide perovskites are competitive candidate as next‐generation flexible photodetectors (PDs) materials due to the remarkable photoelectric properties, enhanced heat stability, and mechanical flexibility. However, constructing low‐cost flexible perovskites PDs with high photodetection performance, good operation stability and mechanical robustness, and manufacturing corresponding flexible PDs array have been a challenge. Herein, the PbCl2 and Zinc(II) Dibenzyldithiocarbamate (Zn(DBDTC)2) are employed to modify bottom and top interface of CsPbIBr2 perovskite layer, respectively, to passivate surface trap state, enhance hydrophobicity and resist phase segregation, and improve interface contact. Consequently, the self‐powered champion PDs with low‐cost Bi2Te3 electrode reach a responsivity of 0.38 A W−1 and a maximum detectivity of 3.44 × 1013 Jones at 570 nm, and maintain the outstanding long‐term and operational stability without additional encapsulation. Meanwhile, the HTL‐free flexible PDs based on low‐temperature CsPbIBr2 perovskite layer exhibit impressive photodetection performance and mechanical robustness in bending test. More importantly, the flexible PDs array (5 × 5 pixels) and corresponding imaging system are fabricated with uniform and clear imaging results under flatting and bending state. This research is of great significance for the application of stable and high‐performance inorganic perovskites PDs and flexible array imaging systems. [ABSTRACT FROM AUTHOR]

Self-powered full-spectrum photodetectors (PDs) offer numerous advantages, such as broad application fields, high precision, efficiency, and multi-functionality, which represent a highly promising and potentially valuable class of detectors for future development. However, insensitive response to solar-blind ultraviolet (UV) and complex and expensive preparation processes greatly limit their performance and practical application. In this study, a self-powered full-spectrum Bi2Se3/a-Ga2O3/p-Si heterojunction PD with high sensitivity for solar-blind UV band prepared by a simple and low-cost two-step synthesis method is presented. Experiments results reveal that the developed PD has an excellent performance, such as high sensitivity from 200 to 850 nm, and a responsivity of 1.38 mA/W as well as a detectivity of 3.22 × 1010 Jones under 254 nm light at zero bias. Additionally, the unencapsulated device displays exceptional stability and imaging capabilities. It is expected that Bi2Se3/a-Ga2O3/p-Si heterojunction PD with a simple and low-cost synthesis method has great potential for self-powered full-spectrum photodetectors. [ABSTRACT FROM AUTHOR]