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High‐speed and sensitive UV–Vis photodetectors have been constructed based on a typical 1D van der Waals material, antimony sulfide (Sb2S3). Impressively, the Sb2S3 nanowire photodetector demonstrates pronounced photosensitivity exhibiting a remarkable on/off ratio of ≈2800 under a power density of 318 mW cm−2. In addition, a high responsivity, an outstanding detectivity, and a short response/recovery time of 270 A W−1, 4.37 × 1013 Jones, and 10/12 ms are achieved. The competitive photosensitivity is associated with the intrinsic Mie resonance of the Sb2S3 nanowire, which is conducive to enhancing the coupling of the Sb2S3 photosensitive channel with incident light. By virtue of the unique 1D structural nature in both intrinsic and extrinsic perspectives, the Sb2S3 nanowire photodetectors manifest distinct polarization‐discriminating photoresponse with the optimal dichroic ratio reaching ≈7.2. Moreover, the Sb2S3 nanowire photodetectors demonstrate stable photoresponse from room temperature to 160 °C, and these nanodevices are durable against long‐term high‐temperature heating treatment at up to 300 °C. Taking advantage of the excellent thermal robustness, high‐temperature‐proof optoelectronic imaging and dual‐channel optical communication applications are demonstrated based on low‐dimensional van der Waals materials. On the whole, this study provides a new option for an advanced multifunctional optoelectronic system in extreme working environments. [ABSTRACT FROM AUTHOR]

Herein, a facile, catalyst-free, and dry topochemical transformation strategy for transforming the Bi2S3 nanowires to the Bi2Se3 nanowires, which has been realized through an atmospheric pressure high-temperature selenization treatment, has been developed. The complete topochemical transformation has been verified by combining x-ray diffraction, Raman spectroscopy, energy dispersive spectrometer, x-ray photoelectron spectroscopy, transmission electron microscopy, and selected area electron diffraction measurements. Systematical optical characterizations, including polarization-resolved optical microscopy images and polarization-dependent Raman spectra, have revealed the strong anisotropy of the Bi2Se3 nanowires. Furthermore, finite-different time-domain simulations have consolidated that the Bi2Se3 nanowires possess highly anisotropic absorption cross sections across the ultraviolet to far infrared spectral range, laying a solid foundation for the realization of ultra-broadband polarized optoelectronic applications. On the whole, this pioneering study depicts a unique avenue for topological material design accompanied with the integration of additional functionalities beyond the intrinsic counterparts, opening up an attractive research field for polarized photonics and optoelectronics. [ABSTRACT FROM AUTHOR]

Low‐dimensional van der Waals materials (vdWMs) have attracted worldwide interest on account of numerous advantages including self‐passivated surface, high carrier mobility, excellent flexibility, etc. Among multiple vdWMs, Sb2Se3 stands out due to its high light absorption coefficient, environmentally friendly components, excellent stability, and abundant reserve. However, limited effective wavelength range and unscalable preparation have been obstinate issues standing in the way of further development. Herein, pulsed‐laser deposition (PLD) has been developed for synthesizing Sb2Se3 nanofilms, and wafer‐scale deposition has been realized. The PLD‐derived Sb2Se3 photodetector demonstrates broadband photoresponse across UV to NIR. First‐principles calculations have determined that this is because the formation of Se vacancies can result in a reduction of the bandgap. Upon 635 nm illumination, an optimal responsivity of 2.68 A W−1 has been achieved, corresponding to an external quantum efficiency of 524% and a specific detectivity of 1.34 × 1012 Jones. Furthermore, the device manifests a short response/recovery time of ≈2/1 ms. Proof‐of‐concept broadband imaging as well as fitness monitoring (respiratory rate & heart rate) have been realized. Profited from the scalable preparation, an array of Sb2Se3 photodetectors have been produced, exhibiting qualified device‐to‐device variation. On the whole, this study has depicted an attractive landscape for next‐generation integrated optoelectronics. [ABSTRACT FROM AUTHOR]

By virtue of the high carrier mobility, diverse electronic band structures, excellent electrostatic tunability, easy integration, and strong light-harvesting capability, 2D layered materials (2DLMs) have emerged as compelling contenders in the realm of photodetection and ushered in a new era of optoelectronic industry. In contrast to powered devices, self-driven photodetectors boast a wealth of advantages, notably low dark current, superior signal-to-noise ratio, low energy consumption, and exceptional compactness. Nevertheless, the construction of self-driven 2DLM photodetectors based on traditional p-n, homo-type, or Schottky heterojunctions, predominantly adopting a vertical configuration, confronts insurmountable dilemmas such as intricate fabrication procedures, sophisticated equipment, and formidable interface issues. In recent years, worldwide researchers have been devoted to pursuing exceptional strategies aimed at achieving the self-driven characteristics. This comprehensive review offers a methodical survey of the emergent paradigms toward self-driven photodetectors constructed from 2DLMs. Firstly, the burgeoning approaches employed to realize diverse self-driven 2DLM photodetectors are compiled, encompassing strategies such as strain modulation, thickness tailoring, structural engineering, asymmetric ferroelectric gating, asymmetric contacts (including work function, contact length, and contact area), ferroelectricity-enabled bulk photovoltaic effect, asymmetric optical antennas, among others, with a keen eye on the fundamental physical mechanisms that underpin them. Subsequently, the prevalent challenges within this research landscape are outlined, and the corresponding potential approaches for overcoming these obstacles are proposed. On the whole, this review highlights new device engineering avenues for the implementation of bias-free, high-performance, and highly integrated 2DLM optoelectronic devices.

In this study, cost-efficient atmospheric pressure chemical vapor deposition has been successfully developed to produce well-aligned high-quality monocrystalline Bi 2 S 3 nanowires. By virtue of surface strain-induced energy band reconstruction, the Bi 2 S 3 photodetectors demonstrate a broadband photoresponse across 370.6 to 1310 nm. Upon a gate voltage of 30 V, the responsivity, external quantum efficiency, and detectivity reach 23 760 A W -1 , 5.55 × 10 6 %, and 3.68 × 10 13 Jones, respectively. The outstanding photosensitivity is ascribed to the high-efficiency spacial separation of photocarriers, enabled by synergy of the axial built-in electric field and type-II band alignment, as well as the pronounced photogating effect. Moreover, a polarization-discriminating photoresponse has been unveiled. For the first time, the correlation between quantum confinement and dichroic ratio is systematically explored. The optoelectronic dichroism is established to be negatively correlated with the cross dimension ( i.e. , width and height) of the channel. Specifically, upon 405 nm illumination, the optimized dichroic ratio reaches 2.4, the highest value among the reported Bi 2 S 3 photodetectors. In the end, proof-of-concept multiplexing optical communications and broadband lensless polarimetric imaging have been implemented by exploiting the Bi 2 S 3 nanowire photodetectors as light-sensing functional units. This study develops a quantum tailoring strategy for tailoring the polarization properties of (quasi-)1D material photodetectors whilst depicting new horizons for the next-generation opto-electronics industry.