Epitaxial Growth of Topological Insulators on Semiconductors (Bi₂Se₃/Te@Se) toward High‐Performance Photodetectors

Abstract

Heterojunctions, composed of different materials, are widely explored in optoelectronic devices thanks to their unique advantages, such as high carrier mobility and excellent photoelectronic characteristics. In this work, Bi2Se3/Te@Se heterojunctions (Bi2Se3/Te@Se) are synthesized through the epitaxial growth of Bi2Se3 nanosheets (Bi2Se3 NTs) on tellurium@selenium nanotubes (Te@Se NTs) by using a low‐cost and facile solvothermal process. Bi2Se3/Te@Se are further applied in high‐performance photoelectrochemical (PEC)‐type photodetection due to the advantages of broadband optical response and fast carrier relaxation time. The PEC results demonstrate that the as‐prepared photodetectors have pronounced photoresponse behavior from the ultraviolet to visible band with self‐driven ability and excellent long‐term stability. It is anticipated that this work provides a new strategy for epitaxial growth of topological insulators on semiconductors for designing new heterojunctions toward high‐performance optoelectronic devices.

Two-Dimensional Tellurium: Progress, Challenges, and Prospects

“…11 b–d. Following this study, Zhang et al [ 139 , 140 ] demonstrated photodetectors based on Te@Bi and Te/Bi 2 Se 3 @Se heterojunctions. For the Te@Bi heterojunction, the corresponding photocurrent density and photoresponsivity in 0.5 M KOH solution as a function of incident laser power with a wavelength of 365 nm are presented in Fig.…”

Ultra‐Small 2D PbS Nanoplatelets: Liquid‐Phase Exfoliation and Emerging Applications for Photo‐Electrochemical Photodetectors

“…The P ph further increases to 21.96 µA cm −2 under the irradiation of level IV, which is higher than those of the current state‐of‐the‐art PEC‐type PDs based on heterojunction nanomaterials such as Te@Bi, Te@Se, Bi 2 Se 3 /Te@Se NTs, and Bi/Te NSs (Table 2). [ 41–44 ] Interestingly, the calculated P ph and R ph of 3.5 g L −1 2D PbS NPLs‐based PDs are about 2.8 times of those based on 1 g L −1 2D PbS NPLs under the irradiation of 400 nm, while the ratios are 2.5, 3.2, 2.5, and 3.2 under the irradiation of 350, 475, 550, 650 nm lasers, respectively. The observed ≈200% photo‐response enhancements are in good agreement with the loading ratio (3.5:1), indicating that the 2D PbS NPLs are uniformly dispersed on the ITO glass (Scheme insert in Figure 6b).…”

PbSe Nanocrystals Produced by Facile Liquid Phase Exfoliation for Efficient UV–Vis Photodetectors

“…For instance, 0.15/0.16 s is detected at 400 nm while it increases to 0.41/0.48 s at 650 nm laser in 0.001 m KOH. In addition, a fast t res / t rec time of 0.12/0.13 s has been achieved in 0.1 m KOH at 650 nm, which is a significantly lower value than or other nanomaterials such as InSe, [ 41 ] Bi 2 Se 3 /Te@Se, [ 52 ] and BP. [ 53 ] The low t res / t rec time can be ascribed to the fast generation and recombination of photo‐generated holes and electrons, which can be enhanced by tuning the light wavelength or improving the KOH concentration.…”