Study of Photoregeneration of Zinc Phthalocyanine Chemiresistor after Exposure to Nitrogen Dioxide
, Martin Hruška 1, Přemysl Fitl 1, Virginie Gadenne 3, Mykhailo Vorokhta 2,*, Iva Matolínová 2 and Martin Vrňata 1,*Round 1
Reviewer 1 Report
This is a rather interesting article, however, in my opinion, the method of measuring sensor properties is incorrect and does not allow us to unambiguously come to the conclusions that the authors make.
I. First of all, we are talking about the data presented in Fig. 5a and 5b. The authors simultaneously change two parameters: the temperature (55C in Fig. 5a and 100C in Fig. 5b) and the radiation wavelength (723-630 nm in Fig. 5a and 518-441 nm in Fig. 5b). The authors claim that the shorter wavelengths were more effective in photoregeneration (indeed, this can be noticed for the data obtained at the same temperature), and a threshold wavelength was determined as 550 nm (this statement is not confirmed by any data provided). In addition, it is completely unclear how the resistance of the films changes when NO2 is removed from the atmosphere in dark conditions (before the light is turned on).
The authors should provide experimental data showing: 1) the results of measuring the sensor properties at 55C when irradiated with light with a wavelength of 550 nm or less; 2) the results of measuring the sensor properties at 100C when irradiated with light with a wavelength of 550 nm or more; the results of measuring the resistance of films at 55C and 100C after removing NO2 from the atmosphere under dark conditions.
II. The second significant comment concerns the synchronization of changes in the composition of the gas phase and lighting. In all cases, the authors first removed NO2 from the atmosphere and then turned on the lighting for photoregeneration. This is easy to do in the laboratory, but this measurement mode is not suitable for practical use. Resistive gas sensors are designed to work independently, without the participation of an operator. That is, you can set the protocol for switching the temperature mode and the lighting mode. At the same time, in real conditions, the change in the concentration of the detected gas is spontaneous, measured using a sensor, but not set by the operator. Therefore, the time of switching on the light for regeneration can not be synchronized with the change in the composition of the atmosphere.
The authors should carry out additional measurements under periodic illumination conditions both in pure air and in the presence of various NO2 concentrations. An example of such measurements with periodic illumination can be found here 10.1016/j.snb.2014.08.091.
Author Response
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Author Response.pdf
Reviewer 2 Report
In this paper, study of photoregeneration of zinc phthalocyanine chemiresistor after exposure to nitrogen dioxide. Based on these studies, the mechanism of nitrogen dioxide interaction with zinc phthalocyanine both under LED illumination and in dark conditions is proposed. The manuscript is well organized and the results support the conclusions. I think it can be accepted after major revision.
- Formula 1-3 is wrong in typesetting and the author needs to revise it.
- The summary part is too cumbersome and needs to be simplified, and there are no references in this part.
- In order to show the advantages of this work, the author needs to give a table comparing with the previous work.
- About “chemiresistive sensing”, some related references need to be mentioned, such as:
- Morphology-controlled electrochemical sensing properties of CuS crystals for tartrazine and sunset yellow; Novel hierarchical sea urchin-like Prussian blue@palladium core-shell heterostructures supported on nitrogen-doped reduced graphene oxide: Facile synthesis and excellent guanine sensing performance.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Comments are attached below
Comments for author File: Comments.pdf
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The article can be accepted in its present form.
Reviewer 2 Report
The article has been modified by the system and can be received.
Reviewer 3 Report
Accept
