Surfactant-Free Synthesis of Nb₂O₅ Nanoparticles Anchored Graphene Nanocomposites with Enhanced Electrochemical Performance for Supercapacitor Electrodes

Round 1

Reviewer 1 Report

The article entitled "Surfactant Free Synthesis of Nb2O5 Nanoparticles Anchored Graphene Nanocomposites with Enhanced Electrochemical Performance for Supercapacitor Electrodes" by authors P. Nagaraju et al. is quite interesting for the scientific comunity because is about Nb2O5/G nnaocomposites synthesized via a facile in-situ microwave irradiation method. This can be used as electrodes in supercapacitors devices with a good performance. The article describes in deep detail all the characterization of this nanomaterials so the article is ready for publication in the present format. 

Author Response

Very very thank you for suggestions and comment.

Reviewer 2 Report

The authors presented surfactant-free synthesis of Nb2O5 nanoparticles anchored graphene nanocomposites with enhanced electrochemical performance for supercapacitor electrodes. After introduction of graphene to the composite, the capacitive performance of electrode is significant enhanced as compared with the bare Nb2O5 electrode. The subject of the article is interesting and adds significant contribution to the field of supercapacitors. I recommend the publication of the article after some clarifications from the authors.

The amount of Nb2O5 in the Nb2O5/G nanocomposite and the specific surface area of the bare graphene should be provided. It would be helpful if the authors may identify the exact capacitance of graphene form the composite electrode. The supercapacitive performance of the pure graphene electrode should be provided. Please add an equivalent circuit to the inset of Fig. 13 and use it to fit the Nyquist plots. Z’’ in Fig. 13 should be -Z’’. Please give a table, showing the parameters obtained from equivalent circuit of EIS. It would be helpful if the authors may identify the changes in morphology (SEM) or microstructure (TEM) of the Nb2O5/G nanocomposite after cycling test, showing good stability of the proposed electrode materials. The composite electrode introduced is not a supercapacitor at all. Charge-discharge profiles at lower rate show the behavior identical to typical battery materials. This is the reason that such a high specific capacitance has been obtained. The charge-storage mechanism of the composite electrode should be added to the manuscript.

Author Response

please see the attachment.

Author Response File: Author Response.pdf