Sensing application of an optical fiber dip coated with L-Cystein ethyl ester hydrochloride capped ZnTe quantum dots

Abstract

Optical fiber in conjunction with ZnTe quantum dots (QDs) is investigated for sensing application. ZnTe QDs, are synthesized by a simple chemical bottom up approach. Quantum dots are capped with L-Cystein ethyl ester hydrochloride (LEEH), to increase their stability. Then LEEH capped ZnTe QDs, whose size is estimated as 2.29 nm by effective mass approximation (EMA), are dip-coated on a cladding removed optical fiber. Different concentrations of alcohol and ammonia are used to investigate the sensing behavior. It is found that sensitivity of the sensor increases with the use of QDs for both alcohol and ammonia.

Fiber Optics for Sensing Applications in a Review

“…As a result, this evanescent field has little or no contact with the material that surrounds the cladding. To address this, claddingfree optical fiber and tapered optical fiber [78][79][80][81][82] have been introduced for sensing applications, and they can be extremely sensitive to the index change of the analyte in the surrounding medium. However, due to its low mechanical strength and figures of merits, the utilization of cladding removed optical fiber suffers.…”

“…A new approach based on the manipulation of colloidal gold nanoparticles in the evanescent field of a waveguide was developed to further improve the proportion of evanescent field in a tapered optical fiber. [78,[83][84][85].…”

“…The detection level was discovered to be 0.326gm/dL. Because the usual albumin level in healthy human blood serum is between 3.5 and 5.5gm/dL, the TFOBS can be used as a low-cost accurate albumin sensor [78].…”