Electrospinning Preparation of GaN:ZnO Solid Solution Nanorods with Visible-Light-Driven Photocatalytic Activity toward H2 Production
, Huiling Zhong 1,2, Xinpin Liu 1,2, Qingrong Qian 1,2, Yongjin Luo 1,2, Liren Xiao 1,2,* and Hun Xue 1,2,*Round 1
Reviewer 1 Report
The authors presented the main results obtained regarding the electrospinning preparation of GaN:ZnO solid solution nanorod with visible-light driven photocatalytic activity toward H2 production.
The paper is sound, original, interesting, well-organized and clearly presented.
The novelty of this manuscript consists in the study of the nanorod GaN:ZnO solid solutions prepared using a electrospinning method for photocatalytic H2 production under visible-light irradiation.
The references are up to date, appropriate and adequate to related and previous work.
I suggest the following corrections:
Page 1, line 35 - “…water splitting was published in 1972.” instead of “…water splitting in 1972.”
Page 2, line 65 - “…for the first time the nanorod…” instead of “…for the first time of the nanorod…”
Page 2, line 77, 84 - “N,N-dimethylformamide” instead of “N, N-dimethylformamide”
Page 2, line 80 - “…and were used without…” instead of “…and used without…”
Page 2, lines 88-89 - “…the solution was delivered by a syringe with a flow rate of 0.6 mL·h-1 and using a high voltage of 28.5 kV…” instead of “…the solution was moved by syringe with 0.6 mL·h-1 flow rate and using a high voltage 28.5 kV…”
Page 3, line 122 - “…methyl alcohol as the role of sacrificial agent…” instead of “…methyl alcohol as the hole sacrificial agent…”
Page 6, line 188 - “…size of nanocrystallite…” instead of “…size of nanocrystalline…”
Author Response
Please see the attachment.
Author Response File: 
Author Response.doc
Reviewer 2 Report
The manuscript presents the synthesis and characterization of electrospun GaN:ZnO nanofibers and their applications for H2 production under visible light. The concept of using electrospinning as the synthesis method seems to be novel for the GaN:ZnO system, and the characterization of the nanorods nitrated with 3 different temperatures is relatively thorough. But the manuscript can improve its quality significantly by more careful proofreading and address the following comments.
- Consider citing the following paper. It is not related to me but it seems to be quite relevant to the manuscript.
- Jing Li et al., Band-Gap Tunable 2D Hexagonal (GaN)1–x(ZnO)x Solid-Solution Nanosheets for Photocatalytic Water Splitting, ACS Appl. Mater. Interfaces 2020, 12, 7, 8583–8591.
- It is not yet clear why S_850 possesses more surface area than the other two samples.
- The manuscript said that GaN:ZnO takes the wurtzite structure, which is typically in a hexagonal prism shape. According to the SEM images, S_850 takes the form of a square rod. But S_750 and S_950 do not show the square shape clearly. Why?
- Zn in ZnO is not stable in a reducing environment (like NH3) at high temperatures. During the nitridation step, did you observe any loss of elemental Zn? Did the stoichiometry of the nanorod change because of the different nitridation temperature?
- How about Zn3N2 (zinc nitride)? Any concurrent formation of zinc nitride?
- Figure 4(e): What is the main culprit for the performance reduction for the subsequent runs?
- Line 94: It says “and then the as-spun nanofibers were calcined at 400C…” Does it mean that the authors prepared for other as-spun nanofibers without nitridation (as a control)? Or were the as-nitrided samples calcined at 400C? It is quite confusing.
- Line 200-201: It says “The sequence is in accordance with the photocatalytic activity order.” But is the trend of photocatalytic activity opposite to the PL intensity? It is again confusing.
- This paper contains numerous grammatical and typographical errors. Some examples are listed below:
- Line 36: “mental” should be “metal”
- Line 45: “ranged” should be “ranging”
- Line 50: “cocatalysts” should be “cocatalyst”
- Line 53: “synthesis” should be “synthesized”
- Line 58: “is a proven” should be “has been proved as a”
- Line 61: “of” should be “to”
- Line 180: “HTEM” should be “HRTEM”
- Line 252: “with disparate specific surface areas” should move to the end of the sentence.
There are a lot more items to be fixed. Consider working with a professional proofreader for better readability.
Author Response
Please see the attachment.
Author Response File: Author Response.doc
