Visible Near-Infrared Photodetection Based on Ta2NiSe5/WSe2 van der Waals Heterostructures

Abstract

The increasing interest in two-dimensional materials with unique crystal structures and novel band characteristics has provided numerous new strategies and paradigms in the field of photodetection. However, as the demand for wide-spectrum detection increases, the size of integrated systems and the limitations of mission modules pose significant challenges to existing devices. In this paper, we present a van der Waals heterostructure photodetector based on Ta2NiSe5/WSe2, leveraging the inherent characteristics of heterostructures. Our results demonstrate that this detector exhibits excellent broad-spectrum detection ability from the visible to the infrared bands at room temperature, achieving an extremely high on/off ratio, without the need for an external bias voltage. Furthermore, compared to a pure material detector, it exhibits a fast response and low dark currents (~3.6 pA), with rise and fall times of 278 μs and 283 μs for the response rate, respectively. Our findings provide a promising method for wide-spectrum detection and enrich the diversity of room-temperature photoelectric detection.

Self-Powered Photodetector with High Efficiency and Polarization Sensitivity Enabled by WSe2/Ta2NiSe5/WSe2 van der Waals Dual Heterojunction

“…On the other hand, proper selection of 2D materials is also an essential parameter to construct high-efficiency and multifunctional photodetectors. Ta 2 NiSe 5 possesses a layered compound stacked by weak vdW interactions and crystallizes in a noncentrosymmetric monoclinic structure with the C2/c space group which makes it strong in-plane anisotropy. − Unlike most transition metal dichalcogenides (TMDs), bulk Ta 2 NiSe 5 not only has a direct band gap of 0.33 eV but maintains its direct band gap nature even thinned to a monolayer. − Moreover, Ta 2 NiSe 5 has a high carrier mobility of 161.25 cm 2 V –1 s –1 , excellent air stability, and ultrabroadband absorption simultaneously. All of these merits make Ta 2 NiSe 5 an ideal candidate for constructing high-performance phototransistors ,, or photodiodes. − ,, However, multifunctional self-powered photodetector with high efficiency and polarization sensitivity based on Ta 2 NiSe 5 still remains a challenging issue.…”

“…All of these merits make Ta 2 NiSe 5 an ideal candidate for constructing highperformance phototransistors 40,44,45 or photodiodes. [41][42][43]46,47 However, multifunctional self-powered photodetector with high efficiency and polarization sensitivity based on Ta 2 NiSe 5 still remains a challenging issue.…”