Wavelength Dependent Graphene Oxide-Based Optical Microfiber Sensor for Ammonia Gas

Abstract

Ammonia detection in ambient air is critical, given its implication on the environment and human health. In this work, an optical fiber tapered to a 20 µm diameter and coated with graphene oxide was developed for absorbance response monitoring of ammonia at visible (500–700 nm) and near-infrared wavelength regions (700–900 nm). The morphology, surface characteristics, and chemical composition of the graphene oxide samples were confirmed by a field emission scanning electron microscope, an atomic force microscope, X-ray diffraction, and an energy dispersion X-ray. The sensing performance of the graphene oxide-coated optical microfiber sensor towards ammonia at room temperature revealed better absorbance response at the near-infrared wavelength region compared to the visible region. The sensitivity, response and recovery times at the near-infrared wavelength region were 61.78 AU/%, 385 s, and 288 s, respectively. The sensitivity, response and recovery times at the visible wavelength region were 26.99 AU/%, 497 s, and 192 s, respectively. The selectivity of the sensor towards ammonia was affirmed with no response towards other gases.

3D Solar Evaporation Enhancement by Superhydrophilic Copper Foam Inverted Cone and Graphene Oxide Functionalization Synergistic Cooperation

“…The 3D inverted conical solar evaporator with a cone's apex angle of 45° provides an enhanced projected area for the light incidence while maintaining a reasonable height for the water transport toward the top of the cone. [ 3a ] The implementation of the nano‐structures modifies the chemical and physical properties of the foam inducing its superhydrophilic wetting behavior, [ 26 ] henceforth referred to as SHiCF. It is worth noting that the PCF can be easily bent and folded into almost any 3D desired configuration maintaining its structure and shape under water load even after hours or days of operation, while the inner microscale pores act as optical traps allowing the repeated absorption of a large amount of reflected light experiencing multiple diffuse reflections along the cone matrix.…”

A Review: Application and Implementation of Optic Fibre Sensors for Gas Detection

“…Another material to find use in the detection of NH 3 is graphene oxides; using graphene oxide and cellulose acetate [172], adhesion of HN 3 to the surface changes the refractive index of LPGs GO-coated tapered optical microfiber. Alternatively, the absorbance characteristics of GO at ~550 nm and ~750 nm can be used to detect the presence of HN 3 [173].…”

Highly Sensitive Photothermal Fiber Sensor Based on MXene Device and Vernier Effect

“…Two-dimensional, nanomaterial-modified MKRs provide new ideas for fiber optic sensors [ 9 , 10 ]. Two-dimensional materials have been gradually explored in academic research concerning their practical applications [ 11 , 12 , 13 , 14 ]. MXenes , a rapidly developing two-dimensional material family, have been reported in many studies since the first successful preparation of MXene Ti 3 C 2 T x in 2011 [ 15 ].…”