From Waste to Energy Storage: Fabrication of FVW-Si/G₅₀₀@C Anode Materials from Photovoltaic Silicon Scrap and Their Enhanced Lithium-Ion Storage Performance

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The topic is highly relevant and original: recycling photovoltaic silicon kerf waste to produce cost-effective Si/C anodes that work well.

The structural design was reasonable (2D graphite conductive 14-star network + RF-derived carbon shell) and tackled Si volume expansion, conductivity, SEI stability. But the novelty over previous Si/C, Si/graphite and Si@C work has not been emphasized enough.

Insufficient experimental detail in the purification procedure of waste Si, ball-milling conditions (mill type, atmosphere, possible contamination, moisture permitted, 900 min justification), Si/graphite/carbon ratios and particle size distribution.

Quantitative information is needed for the RF coating and carbonization process: solution pH, solids content, inert gas conditions, final carbon content and phase composition in FVW-Si/G500@C.

Reference electrode preparation must include active material loading (mg cm⁻²), electrode thickness and whether electrodes were pressed/calendered to improve reproducibility and comparison.

Structural characterization (SEM, XRD, XPS) is mostly conventional, but should be stronger particularly with: TEM or cross-sectional images clearly showing core-shell structure and carbon shell thickness, Scherrer analysis of Si crystallite size, and quantitative XPS fitting (relative amounts Si⁰/oxidized Si and C/O species).

Electrochemical results are promising (high capacity and rate performance), but need clearer quantitative analysis:

How capacity is normalized (per total composite mass vs. per Si mass).

Capacities at each current density for all samples after cycling, plus Coulombic efficiency vs. cycle number plotted.

Quantitative EIS fitting ( equivalent circuit, R_s, R_SEI, R_ct ), ideally before and after cycling.

Long-term cycled (>100 cycles) throughput, with post-mortem electrode analyses (e.g. SEM after cycling), would substantially strengthen the claim of improved stability.

The English writing needs comprehensive editing: eliminate typos, unify units and symbols, end long parentheses, delete the overlap between Highlights and “main findings/implications.”

The Conclusions section is too long and repetitive; it should be reduced to a few focused points on: waste-derived Si source, structural design, major numerical performance, and scalability/industrial relevance.

The work is meaningful and the results promising, but it needs extensive revision if it is to be published.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

In this article, Li et al. reported the fabrication of FVW-Si/G₅₀₀@C anode material from photovoltaic silicon scrap for enhanced lithium-ion storage. The prepared FVW-Si/G500@C electrode delivered a reversible capacity of 951.8 mA h/g after 100 cycles at a current density of 0.2 A/g. Even at a high current density of 1 A/g, it retained a reversible capacity of 230.4 mA h/g. Some minor issues need to be addressed before its publication in this journal.

1. The introduction section lacks a logical flow. Authors are advised to first describe the key bottlenecks of existing Li-ion storage anode materials—and then describe the importance of synthesizing the FVW-Si/G₅₀₀@C electrode. Additionally, authors should clearly write the novelty of this current work.
2. There are some grammatical and typographical errors. Authors should modify all these errors.
3. The motivation of this research should be written in the abstract.
4. TEM image should be provided.   
5. Some relevant articles can be cited in the manuscript for comparison:

https://doi.org/10.1016/j.ccr.2025.217343;

https://doi.org/10.1039/D5SC10185A;

https://doi.org/10.1016/j.jpowsour.2025.237759;

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

1. The section related to the description of SEM images is not clear with respect to figures. In particular, figure 1b is not described or cited in the main text. The caption of figure 1 should contain more details about the difference of each SEM image, rather than just mentioning the material.
2. In figure 4, there are Chinese words that are not understandable by the majority of the readership. Translate in English
3. Figure 5a refers to the cyclic voltammetry of FVW-Si/G500C. The authors should present the CV in a more understandable way: associate to each cycle a unique color and assign the most important peaks to the corresponding reactions in the graph for clarity.
4. EIS measurement lacks a quantitative analysis. The authors should display the equivalent circuit and perform the fitting of the Nyquist plots in order to obtain the charge transfer resistance, to justify the impedance decrease

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

accept in current form

Reviewer 3 Report

Comments and Suggestions for Authors

in figure 5a authors should display colors for each cycles and highlight them in the pictures (black line - cycle 1 etc)