Inkjet-Printed Flexible Piezoelectric Sensor for Large Deformation Applications

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript entitled “Inkjet-printed flexible piezoelectric sensor for large deformation applications”, presents a novel and fully inkjet-printed piezoelectric sensor based on a P(VDF-TrFE) active layer, demonstrating excellent flexibility and performance under large deformations. This work has good structure and reasonable method, and has certain application potential in the field of wearable electronics. But there are several points in the manuscript that need to be added and improved. Here are my specific suggestions:

1. Lack of response curve of output voltage and applied pressure.
2. The minimum pressure detection limit of the sensor should be characterized.
3. How about the response hysteresis behavior of the sensor?
4. The manuscript highlights the sensor's performance under bending tests, but the long-term mechanical stability under repeated cyclic loading is not addressed.
5. A comparison of the performance of existing flexible piezoelectric sensors (for example, in terms of sensitivity and linear response range) is lacking in the manuscript.
6. Some recently works of piezoelectric pressure sensors are suggested to include into the paper, such as Nano Energy, 2022, 100, 107498.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This manuscript presents a fully inkjet-printed flexible piezoelectric sensor based on a P(VDF-TrFE) active layer and silver electrodes on a PI substrate. The work demonstrates promising mechanical flexibility, structural stability under repeated bending, and an appreciable electromechanical response after high-temperature poling. The sensor shows potential for strain and acoustic sensing applications. However, some concerns remain regarding the rigor of the characterization methods and the scientific completeness of the results. The manuscript is recommended to undergo major modification before being considered for publication in Technologies. The comments are as follows:
1.    What is the piezoelectric coefficient of the device? Is its performance comparable to that of commercial PVDF materials?
2.    Is the printed area of the functional layer (PVDF-TrFE) larger than that of the electrode? Given the electrical property differences between PI and silver layers, could this lead to instability during the printing process? Additionally, when printing on a PI substrate, is there a risk of charge accumulation causing instability in inkjet printing?
3.    Since some porosity is inevitable during inkjet printing, could these pores lead to increased leakage current, a higher risk of dielectric breakdown during poling, or a degradation in piezoelectric performance?
4.    As shown in Figure 4b, the inkjet-printed device exhibits negligible piezoelectric response before effective poling. What are the key advantages of this fabrication method?
5.    How stable is the device during long-term operation? It is recommended that cyclic testing be included to evaluate its application potential comprehensively.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The list of comments is attached.

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have addressed the reviewer's concerns and made revision to the manuscript. It is ready for publication.