Rare-Earth-Ion (RE³⁺)-Doped Aluminum and Lanthanum Borates for Mobile-Phone-Interrogated Luminescent Markers

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This article deals with RE doped borates intended for a simple and quick mobile phone based readout. The comparison with a laboratory spectrometer is made. Overall this is an intriguing subject and could very well find its use in everyday life.

The article is written well and is clear and understandable, it reads well. I only have a few remarks, that would help improve the article in my opinion.

I believe that the introduction might be too long, as there is some common knowledge about light and matter interactions that I would rather see in I book not a scientific article,

In line 61 I tend to disagree on the praise to solid state synthesis, as the resultant particle size range is very large and hart to control, as well as it is not energy efficient. I can agree on the simplicity and high yield though.

In line 167, I am not sure I understand what is meant by “strong green region” .

In line 188, it should be “ spin-orbit coupling”.

Can the samples be excited with the smartphone built in light as well?

Comments on the Quality of English Language

There are some grammar mistakes, i.e., words written together without a space and other minor mistakes.

Author Response

Dear Reviewer,

Thank you for the useful suggestions to which we have complied.
Our responses are presented in the attached file.

Kind regards,

Tinko Eftimov

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This manuscript reported the synthesis and luminescent spectra of rare earth doped LaBO₃ and AlBO₃ phosphors, and compared their 3D excitation emission spectra by a standard and mobile phone spectrometer, respectively. Nevertheless, the LaBO₃ phosphors doped with Gd³⁺, Tb³⁺, Eu³⁺, Dy³⁺ and Ce³⁺ mentioned in the manuscript have been reported, introducing these rare earth ions in another AlBO₃ host and discussing their 3D excitation emission spectra does not represent enough novelty, and their spectral response with the mobile phone spectrometer is non-uniform compared to standard spectrometer. Hence, I don’t think this manuscript is suitable for publication in Photonics, and some comments are listed below.

1. In Fig. 2 e) and f), no peaks/bands corresponding to Ce²⁺/Ce³⁺ ions can be found, while authors mentioned that the Ce²⁺ ions generally show efficient luminescence in the UV-VIS spectral region.

2. In Page 13 of 20, the weak signals within 470-570 nm are not observed with the spectrometer is uncommon, and the relevant explanation is not valid.

3. As mentioned in the manuscript, the smartphone can efficiently filter out and attenuate the wavelength under 400 nm and above 670 nm, respectively, but the reason for this phenomenon is not clear.

Comments on the Quality of English Language

There are some obvious grammatical and writing errors, especially lacking reasonable spacing in some sentences.

Author Response

Dear Reviewer,

Thank you for the valuable critical remarks which we have taken into consideration and introduced corresponding changes in the text.

In the attached file please find  our responses and comments.

Kind regards,

Tinko Eftimov

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The authors presented the synthesis and luminescent spectra of rare earth doped aluminum and lanthanum borates intended to serve as narrow excitation-emissithe manuscript, I suggest the manuscript not be accepted in its current form. The authors should pay attention to the following questions.

1. Please see the uploaded attachment that includes the errors to be corrected and questions to be answered.

2. The authors should explain why they chose such combination of dopants as reflected in Table 1. Generally, the samples should be unified as the dopants are similar in the comparing host materials.

3. The authors listed the conclusions of their research findings. They should also referred the application prospects and the future improvement of the work. 

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The English of the whole manuscript should be further improved, especially the gramma.

Author Response

Dear Reviewer,

Thank you very much for your valuable comments, corrections and suggestions.

In the attached file please find our responses in red.

Kind regards,

Tinko Eftimov

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have carefully considered the comments of reviewers and made detailed revisions, so I recommend that this revised manuscript could be published in Photonics in its current version.

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript is improved and now can be considered to be published.