Enhanced Cl₂ sensitivity of cobalt-phthalocyanine film by utilizing a porous nanostructured surface fabricated on glass

Abstract

In this paper, we demonstrate a very simple and effective approach to improve the sensitivity and the low detection limit of cobalt phthalocyanine (CoPc) films towards the detection of chlorine by creating a porous nanostructured surface on a glass substrate via a vapor phase etching process. CoPc films grown on etched glass (CoPc-etched films) exhibited entirely different morphology as compared to CoPc films grown on plain glass (CoPc-plain films). For 60 nm thickness, randomly distributed CoPc nanostructures were grown on the etched surface, whereas the CoPc-plain film showed an elongated granular structure. For 250 ppb Cl 2 exposure, the CoPc-etched film showed a response of $105%, which is $5 times higher than the CoPc-plain film (20%). In addition, it can detect Cl 2 down to 100 ppb concentration; this low detection limit is superior to CoPc-plain film (250 ppb). The improved gas sensing property of CoPc-etched film is ascribed to the presence of more interaction sites for gas adsorption, which is confirmed by charge transport, X-ray photoelectron spectroscopy and Kelvin probe measurement. This novel approach of improving the sensitivity and low detection limit paves a new way for the application of surface etching in the gas sensing field of organic semiconductors.

Improved Cl2 sensing characteristics of reduced graphene oxide when decorated with copper phthalocyanine nanoflowers

“…Chemiresistors on the other hand are found to be comparatively simple, economical, compact in design and consume less power. Extensive reports have been published over last few years for the detection of Cl 2 using various semiconducting oxides, 9,10 conducting polymers 11 and organic molecules 12,13 based nanostructures and thin lm at room temperature.…”

“…[41][42][43][44] We have recently demonstrated the growth of substituted MPcs with nanowire, nanoowers and nano belts morphology for formation of room temperature Cl 2 sensors with detection limit down to ppb level. [38][39][40]45 Very recently Zhao et al 37 reported the growth of single crystal nano column of unsubstituted copper phthalocyanine (CuPc) for room temperature Cl 2 sensor with response of 26% for 80 ppb and Kumar et al 13 reported ve times enhancement in Cl 2 sensing using unsubstituted cobalt phthalocyanine (CoPc) lm on porous nanostructured surface on etched glass in comparison to CoPc lm on plain glass.…”

Cobalt Phthalocyanine Surface Acoustic Wave Sensor for Chloride Sensing in Water Samples

“…For chloride detection, the SAW sensing area was functionalized with a thin layer of cobalt phthalocyanine. Several reasons have motivated this choice: i) Our "know how" in depositing thin layers of CoPc by molecular beam epitaxy, with a perfect control of both thickness and geometry of the zone on which the films are grown, ii) Their frequent use as recognition layers in chlorine gas sensors [35][36][37] and iii) Its particular columnar shape. To the best of our knowledge, this is the first study concerning chloride sensing with SAW sensors.…”

Screen-Printed Electrodes Modified with Metal Phthalocyanines: Characterization and Electrocatalysis in Chlorinated Media

“…This is consistent with the theoretical studies that predict that the sensitivity depends on the metallic center involved [ 30 ]. Although CoPH films have already been employed in the detection of chlorine in previous work [ 31 ], no reduction processes are observed using DRP-410 following the methodology developed in this work. Taking into account the better electrochemical response of DRP-110CUPH, further studies have been carried out using these electrodes.…”