Au-Deposited Ce0.5Zr0.5O2 Nanostructures for Photocatalytic H2 Production under Visible Light
, Maqsood Ahmad Malik 2 and Katabathini Narasimharao 1,*Round 1
Reviewer 1 Report
The authors synthesized an Ce0.5Zr0.5O2 and Au (0.1-1.0 wt.%) deposited Ce0.5Zr0.5O2 materials heterostructure through a by hydrothermal and non-aqueous precipitation methods for visible-driven photocatalytic H2 evolution. This work is well written and interesting. However, some conclusion is not convincing and less rigorous. More explanation and discussion are needed before its publication. Detailed comments are as follows:
1. Please supplement the standard card corresponding to Ce0.5Zr0.5O2 in Fig.1.
2. In Fig.3, please mark the clear lattice stripes of the samples and circle the specific locations of the Au nanoparticles.
3. It is suggested that different samples of Ce3d, Zr3d, O1s and Au4f XPS spectra should be drew in the same graph to compare the binding energy changes. Furthermore, please mark the specific location information of all signal peaks in Fig.6.
4. The author can test the H2 production activity of nanocomposites with more Au load, whether the higher the load, the better the activity of H2 production.
5. The reduction potential of H+ and the oxidation potential of ethanol to acetaldehyde should be added in Scheme 1.
6. The quantitative calculation process of the product of ethanol oxidation (such as of acetaldehyde) should be added.
7. Some important works should be cited in the introduction part (Acta Phys.-Chim. Sin. 2023, 39, 2212009; ACS Catal. 2022, 12, 9994; J. Mater. Sci. Technol. 2024, 169, 148-157; ACS Catal. 2022, 12, 14637; J. Alloys Compd. 2023, 930,167368), and more details should be analyzed.
The authors synthesized an Ce0.5Zr0.5O2 and Au (0.1-1.0 wt.%) deposited Ce0.5Zr0.5O2 materials heterostructure through a by hydrothermal and non-aqueous precipitation methods for visible-driven photocatalytic H2 evolution. This work is well written and interesting. However, some conclusion is not convincing and less rigorous. More explanation and discussion are needed before its publication. Detailed comments are as follows:
1. Please supplement the standard card corresponding to Ce0.5Zr0.5O2 in Fig.1.
2. In Fig.3, please mark the clear lattice stripes of the samples and circle the specific locations of the Au nanoparticles.
3. It is suggested that different samples of Ce3d, Zr3d, O1s and Au4f XPS spectra should be drew in the same graph to compare the binding energy changes. Furthermore, please mark the specific location information of all signal peaks in Fig.6.
4. The author can test the H2 production activity of nanocomposites with more Au load, whether the higher the load, the better the activity of H2 production.
5. The reduction potential of H+ and the oxidation potential of ethanol to acetaldehyde should be added in Scheme 1.
6. The quantitative calculation process of the product of ethanol oxidation (such as of acetaldehyde) should be added.
7. Some important works should be cited in the introduction part (Acta Phys.-Chim. Sin. 2023, 39, 2212009; ACS Catal. 2022, 12, 9994; J. Mater. Sci. Technol. 2024, 169, 148-157; ACS Catal. 2022, 12, 14637; J. Alloys Compd. 2023, 930,167368), and more details should be analyzed.
Author Response
Responses were added in the file.
Author Response File: 
Author Response.docx
Reviewer 2 Report
In this present work, the author reported a “Au deposited Ce0.5Zr0.5O2 nanostructures for photocatalytic H2 production under visible light works are interesting. Moreover, the nanostructured Ce0.5Zr0.5O2 and Au (0.1-1.0 wt.%) deposited Ce0.5Zr0.5O2 materials were synthesized by hydrothermal and non-aqueous precipitation methods using gold acetate as chloride free Au precursor. The band gap value was lowered after Au nanoparticles were deposited on the surface of Ce0.5Zr0.5O2. The 1.0 wt.% Au deposited Ce0.5Zr0.5O2 exhibited the highest photocatalytic activity for H2 production (3210 µmol g-1) due to low band gap, presence of more oxygen vacancies and porous character. The overall scientific organization of this article is satisfactory with some minor revisions as must be needed before acceptance. I have the following concerns.
1. What is the benefit of the selected composition? Why did the authors choose to select Ce0.5Zr0.5? Can you check with changes in the ratio of Ce and Zr concentration?
2. The authors must provide quantitative data to prove the composition. Could you explain the weight % of as-synthesized 1.0 wt.% Au deposited Ce0.5Zr0.5O2 catalysts by either EDS and/or XPS spectra?
3. An author may add the photoluminescence or EIS spectra for further study of the e-/h+ recombination rate. Because the property is very essential in the photocatalytic performance.
4. Moreover, the more morphological investigation after recyclability tests, such as the SEM image of the 1.0Au-Ce0.5Zr0.5O2 catalyst.
5. Consistently express the units used in the manuscript. Please keep the Figure. * or Fig.* style consistent throughout the main content. Also, use either ml or mL as an example.
6. Abstract and conclusion part since it's more identical. Authors should revise with the different also the proper key results including numerical hints.
Author Response
Responses to reviewer comments are included in the file.
Author Response File: Author Response.docx
