High-quality CdTe nanowires: Synthesis, characterization, and application in photoresponse devices

Abstract

High-quality straight and multiply kinked CdTe nanowires (NWs) were synthesized by the facile chemical vapor deposition method at 600 °C. The as-synthesized NWs were characterized by scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive x-ray spectroscopy, and photoluminescence (PL) spectroscopy. The straight CdTe NWs have single crystalline zinc blende structure with growth direction along the ⟨111⟩ direction. Their PL spectra consist only sharp near band edge emission around 824.3 nm. The multiply kinked CdTe NWs contain one or more fixed (∼125.2°) angle joints; each arm of the kinked NWs is single crystalline with similar selected area electron diffraction pattern as that of the straight CdTe NWs. The two growth directions in the multiply kinked CdTe NWs are ⟨200⟩ and ⟨111⟩. Single straight and kinked CdTe NW photoresponse devices were fabricated and testified to have high photocurrent decay ratio, high responsivity, fast response time, and no decay tail under 633 nm He–Ne laser illumination. These straight and multiply kinked CdTe NWs may open up potential applications in the bottom-up integrated nanoelectronic and nanophotonic systems, such as photovoltaic and multiterminal nanodevices etc.

The Effect of Plasmonic Nanoparticles on the Optoelectronic Characteristics of CdTe Nanowires

“…Table 2 summarizes the key metrics of the present device and other CdTe nanostructure based photodetectors. It is visible that after surface modification, both G and R are higher than other CdTe nanostructures based photodetectors, including CdTe nanoribbons, CdTe quantum dots, and high‐crystallinity CdTeNWs . We ascribe the improved device performance to the following two factors: (a) Photonic enhancement.…”

“…Besides, CdTe can act as visible light photodetector as well . Dai et al demonstrated that single‐crystalline CdTe nanowires from chemical vapor deposition method exhibited obvious photoresponse to 633 nm light illumination, with high photocurrent decay ratio, high responsitivity and fast response time . What is more, it is also reported that CdTe nanoribbons converted from ZnTe nanobelts were ultra‐sensitive to visible‐NIR illumination with high gain and responsivity .…”

Band‐Selective Infrared Photodetectors with Complete‐Composition‐Range InAsxP1‐x Alloy Nanowires

“…Among them, nanowire PDs, which can convert optical signals to electrical signals in nano/micrometer‐scale devices, are key functional units for on‐chip information communication and processing . Already, much work has been devoted to investigating NW‐based PDs . However, most of the reported nanowire PDs are limited to the visible and ultraviolet spectral regions, and little work has been reported in the infrared (IR) region .…”

Heterojunctions Based on II-VI Compound Semiconductor One-Dimensional Nanostructures and Their Optoelectronic Applications

“…The photodetectors were run under white light illumination with an intensity of 62.5 µW cm −2 and presented excellent stability and reproducibility even at 600 Hz. On the other hand, the heterojunction devices reveals small rise time (1.2 ms) and fall time (1.58 ms), which are much faster than the reported CdTe nanowires and CdTe nanoribbons based photodetectors [63][64][65]. Wu et al fabricated CdS nanoribbon/Si heterojunctions based photodiodes and obtained smaller rise time of 300 µs and fall time of 740 µs under white light illumination with intensity of 5.3 mW cm −2 ( Figure 12) [61].…”