Fast visible-UV light nanobelt photodetector

(a) The schematic diagram of CdS-CdSxTe1-x-CdTe nanobelts. (b) Schematic diagram of electron-hole pair separation and transfer in the CdS-CdSxTe1-x-CdTe heterostructure photodetector. Credit: ©Science China Press

As a representative II-VI semiconductor, CdS is a promising material for visible-UV light detection. However, for pure NWs/NBs based photodetectors, fast photoresponse speed and high sensitivity cannot be achieved simultaneously because of the surface reaction.

Recently, group of Qing Yang in Zhejiang University demonstrates a CdS-CdSxTe1-x-CdTe core-shell nanobelt photodetector, which possesses both high sensitivity and fast speed. The CdS-CdSxTe1-x-CdTe nanobelts were fabricated by introducing CdTe in the growth of CdS nanobelt.

Because of the special growth condition, ternary crystal CdSxTe1-x alloy layers was formed between CdS and CdTe layers, thus CdS-CdSxTe1-x-CdTe core-shell structure was obtained. The fastest response time of this photodetector was demonstrated to be 11us, which is the fastest nanobelt photodetector based on CdS.

The improvement of the response speed is ascribed to the forming of heterojunction among CdS, CdSxTe1-x and CdTe layers, which suppresses the surface reaction. In addition, the detection light spectrum has covered a wide range from 355 to 785 nm. Compared with pure CdS or CdTe nanostructure-based photodetectors, the detection spectrum of this photodetector is much extended, covering the whole visible spectrum.

The responsivity and 3 dB bandwidth of the nanobelt photodetector reaches up to 1520 A/W and 22.9 KHz, respectively. Considering the simple fabrication process and the high performance in responsivity, response speed and detection spectrum, the CdS-CdSxTe1-x-CdTe NB photodetectors will find wide applications in optoelectronic nano devices such as optical communications, sensing and imaging.

###

See the article:

Tang M, Xu P, Wen Z, et al. Fast response CdS-CdSxTe1-x-CdTe core-shell nanobelt photodetector. Sci. Bull. (2018) https://doi.org/10.1016/j.scib.2018.08.003
https://www.sciencedirect.com/science/article/pii/S2095927318303785

Media Contact

Yang Qing EurekAlert!

All news from this category: Physics and Astronomy

This area deals with the fundamental laws and building blocks of nature and how they interact, the properties and the behavior of matter, and research into space and time and their structures.

innovations-report provides in-depth reports and articles on subjects such as astrophysics, laser technologies, nuclear, quantum, particle and solid-state physics, nanotechnologies, planetary research and findings (Mars, Venus) and developments related to the Hubble Telescope.

Back to the Homepage

Comments (0)

Write comment

Latest posts

Seawater as an electrical cable !?

Wireless power transfers in the ocean For drones that can be stationed underwater for the adoption of ICT in mariculture. Associate professor Masaya Tamura, Kousuke Murai (who has completed the…

Rare quadruple-helix DNA found in living human cells with glowing probes

New probes allow scientists to see four-stranded DNA interacting with molecules inside living human cells, unravelling its role in cellular processes. DNA usually forms the classic double helix shape of…

A rift in the retina may help repair the optic nerve

In experiments in mouse tissues and human cells, Johns Hopkins Medicine researchers say they have found that removing a membrane that lines the back of the eye may improve the…

Partners & Sponsors

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close