Tailoring the Glass Composition to Increase the Thermal Stability without Impacting the Crystallization Behavior of Oxyfluorophosphate Glass
Round 1
Reviewer 1 Report
The paper offers interesting results that could be relevant to the readership of this journal. It studies the thermal properties of different glasses from the NaPO3 - CaF2 system prepared with different amounts of MgO, Fe2O3, Al2O3, Er2O3 and ErF3 to obtain glass-ceramic with upconversion under pumping. However, some issues need to be addressed in order to make it convincing for the readership.
In the introduction, please avoid the use of expressions as “it is well known…”, “…to name a few” or “…just to cite a few” and cite the articles or applications that are relevant to the research presented in this study.
Page 2 line 55, strange position for reference 14, please revise.
Page 2 line 61, what do the authors mean when they say: “…this system possess low thermal stability”? I suggest expanding the concept a bit.
In the materials and methods section, the labelling of the compositions investigated is a bit confusing. I would suggest rewriting the two first sentences and add a table summarising all the compositions prepared.
Is there any reason to choose an alumina crucible to prepare some of the samples. Also, II think there is a typo in page 2, lines 89 and 90, “Alumina crucible” appears in capital letters.
How did the authors quench the glasses?
The operating conditions of the XRD analysis (scan range, step size and time of acquisition per step) should be specified.
Page 3 line 123, strange position for reference 14, please revise.
Please assign the IR bands and indicate to which band the spectra was normalised to make the discussion clearer.
In figure 3 all the crystalline phases obtained after the heat treatment for each diffractogram should be identified by their respective ICDD-JCPDS card number. Moreover, the software and database used for the phase identification should also be described in the methods section. Also, in fig. 3c, sample 0Fe is plotted in a light grey colour that is difficult to see.
Revise equation 1, it seems that there is a typo in Scherrer's equation.
In figure 6 all the crystalline phases should be identified by their respective ICDD-JCPDS card number in every diffractogram (same as in figure 3).
Author Response
We would like to thank the reviewer 1 for the constructive comments which we tried to answer accordingly.
In the introduction, please avoid the use of expressions as “it is well known…”, “…to name a few” or “…just to cite a few” and cite the articles or applications that are relevant to the research presented in this study.
- introduction was modified as suggested
Page 2 line 55, strange position for reference 14, please revise.
- now changed
Page 2 line 61, what do the authors mean when they say: “…this system possess low thermal stability”? I suggest expanding the concept a bit.
- This means high tendency to crystallize during heat treatment. This is now explained in the introduction
In the materials and methods section, the labelling of the compositions investigated is a bit confusing. I would suggest rewriting the two first sentences and add a table summarising all the compositions prepared.
- We agree with this comment and a table was added
Is there any reason to choose an alumina crucible to prepare some of the samples. Also, II think there is a typo in page 2, lines 89 and 90, “Alumina crucible” appears in capital letters.
- The only reason is because we did not want to melt the Fe containing glasses in the Pt to avoid a potential reaction between Fe and Pt. We don’t think this should be mentioned in the paper
How did the authors quench the glasses?
- We used a “normal” quenching: the glasses were quenched in air. This information is now added in the text
The operating conditions of the XRD analysis (scan range, step size and time of acquisition per step) should be specified.
- some informations are now added. We don’t think the time of acquisition per step is a relevant information to add
Page 3 line 123, strange position for reference 14, please revise.
- we do not find the place of this reference strange. It is at the end of the sentence as it should be. Nonetheless we changed the sentence “Recently, the nucleation and growth behavior of glasses in the NaPO3-CaF2 system was reported by Ojha et al [14].”
Please assign the IR bands and indicate to which band the spectra was normalised to make the discussion clearer.
- we do not think we should do this as it was reported multiple times. We added in the figure caption “The spectra are normalized to the maximum band at 1100 cm-1.”
In figure 3 all the crystalline phases obtained after the heat treatment for each diffractogram should be identified by their respective ICDD-JCPDS card number. Moreover, the software and database used for the phase identification should also be described in the methods section. Also, in fig. 3c, sample 0Fe is plotted in a light grey colour that is difficult to see.
- ICDD-JCPDS card numbers are now added in the text and more information about the software can be found in the experimental section. Figure 3c was also modified.
Revise equation 1, it seems that there is a typo in Scherrer's equation.
- Thank you for noticing this typo which is now corrected.
In figure 6 all the crystalline phases should be identified by their respective ICDD-JCPDS card number in every diffractogram (same as in figure 3).
- now changed
Reviewer 2 Report
ceramics-1164172
This is a very interesting article on how to tailor glass composition to increase the thermal stability without impacting the crystallization behavior of oxyfluorophosphate glasses. The article is well written and well presented. I have two comments though to be considered by the authors:
- Are there any pictures of the glasses to provide?
- Apart from the thermal properties of the investigated glasses presented in table 1, I think it would be nice to add a figure with the DTA thermograms of the synthesized glasses, even as supplementary material
Author Response
Thank you for your comments
1) as the glasses look exactly like the ones we already published their pictures, we decided not to add pictures of the glasses. Additionally, we think that the transmittance spectra are more relevant information. Nonetheless, the manuscript was revised as "The glasses were heat-treated at (Tg+20oC) for 17h and at their respective Tp for 1h as performed in [14]. All the investigated glasses became translucent after heat-treatment. They look similar to those reported in [14]. The decrease in the transmittance was evidenced by the decrease in the transmittance of the glasses after heat-treatment (Fig. 2)."
2) we do not think it is necessary to show the thermograms even in supplementary data as the data are reported in Tables. We hope the reviewer agrees with our decision as it has not impact on the quality of our paper
Reviewer 3 Report
Page 4, Table 1, please provide the standard deviation for each mean sizes.
P4, L140-L146: The authors conclude that the different thermal properties between 0Mg/Al sample and 0Fe sample is due to a contamination with Al2O3 crucible during the thermal treatment for 0Fe sample. Could the authors explain why they used two different crucibles? How many Al2O3 is released from the crucible to the sample? Please, explain it.
P4, L156: The authors should explain what Qn units means within this context.
P6, Figure 3: Please, change the color of the line of the 0Fe sample spectrum.
P6, L201: Please, indicate that the diffraction peak at 2θ = 47° corresponds to (220) crystal plane of CaF2.
P7, L203: For comparing the crystal sizes, one should take in account first the standard deviation of the mean values. Then, is there a significant difference in the sizes upon adding different modifiers?
Figure 4: The legends of the graphs doesn't match with the lines of the graph. The caption should be also checked.
Author Response
We would like to thank the reviewer 2 for the constructive comments which we tried to answer accordingly
Page 4, Table 1, please provide the standard deviation for each mean sizes.
- we estimate that the error bar is about 2nm for all mean size.
P4, L140-L146: The authors conclude that the different thermal properties between 0Mg/Al sample and 0Fe sample is due to a contamination with Al2O3 crucible during the thermal treatment for 0Fe sample. Could the authors explain why they used two different crucibles? How many Al2O3 is released from the crucible to the sample? Please, explain it.
- We did not want to melt the Fe containing glasses in the Pt to avoid reaction. It is well known that the phosphate glasses are corrosive and reacts with the crucible. We do not think that a discussion on Al contamination is needed in this paper. We hope the reviewer agreed with our decision
P4, L156: The authors should explain what Qn units means within this context.
- now added in the manuscript: “These changes indicate that the progressive addition of MgO, Al2O3 and Fe2O3 leads to a depolymerization of the glass network associated with an increase in the Q1 units at the expense of the Q2 units, the Q1 and Q2 units being units with 1 and 2 bridging oxygens per tetrahedron, respectively
P6, Figure 3: Please, change the color of the line of the 0Fe sample spectrum.
- now changed
P6, L201: Please, indicate that the diffraction peak at 2θ = 47° corresponds to (220) crystal plane of CaF2.
- now added. We also added the other crystal planes
P7, L203: For comparing the crystal sizes, one should take in account first the standard deviation of the mean values. Then, is there a significant difference in the sizes upon adding different modifiers?
- we agree about this comment and we added the error bar on the estimation of the size of the crystallite. We also added a sentence as similar results were already observed: “Similar growth of the crystallite size was reported when adding 1.5mol% of TiO2, ZnO and MgO in the base glass [14].”
Figure 4: The legends of the graphs doesn't match with the lines of the graph. The caption should be also checked.
- we don’t understand this comment. We changed the figure caption for clarification
Round 2
Reviewer 3 Report
After reviewing the revised version I confirm that the manuscript is significantly improved and therefore, I suggest to publish it in Ceramics.
