## 4 Conclusions  
The study presented in this work successfully synthesized uniform and well-separated 2D In\({}_{2}\)S\({}_{3}\) nanoflakes through a facile solvothermal method. The sponge-like In\({}_{2}\)S\({}_{3}\) nanoflake electrode produced demonstrated high capacitance, excellent cyclic retention value, and a decent power density. The incorporation of SWNTs in the 2D In\({}_{2}\)S\({}_{3}\) nanoflakes significantly enhanced the cyclic retention of electrons, showcasing the potential of tailoring the SWNT-In\({}_{2}\)S\({}_{3}\) heterostructure for superior electrodes. These findings provide evidence that 2D layered In\({}_{2}\)S\({}_{3}\) electrode materials have promising electrochemical properties, making them a potentially promising next-generation electrode material for supercapacitor applications. Furthermore, the demonstration of the wireless power BLE/PPG module highlights the potential for a wirelessly powered sealed SSC device to act as an efficient battery substitute in wireless health monitoring systems. This study suggests that integrating 2D layered In\({}_{2}\)S\({}_{3}\) electrode materials into SSC devices could result in high-performance supercapacitors that are suitable for use in a wide range of applications, including wireless health monitoring systems.  
Overall, this work represents a significant contribution to the field of electrode material synthesis and provides a foundation for further research into the potential applications of 2D layered In\({}_{2}\)S\({}_{3}\) electrode materials. It is speculated that this research will inspire future studies to explore the full potential of these materials for energy storage and other applications, leading to the development of more efficient and sustainable energy technologies.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app13052958/s1](https://www.mdpi.com/article/10.3390/app13052958/s1)]([https://www.mdpi.com/article/10.3390/app13052958/s1](https://www.mdpi.com/article/10.3390/app13052958/s1)), Figure S1: Full scan XPS spectra of INS1 sample; Figure S2: Bright TEM field image (a) HAADF TEM image, (b) of INS1 electrode sample; Figure S3: Color mapping image of INS0, INS1, INS2, and INS5 samples; Figure S4: EDAX spectra of INS0, INS1, INS2, and INS5 samples; Figure S5: 3T CV curves of (a) INS0, (b) INS1, (c) INS2, and (d) INS5 samples; Figure S6: 3T terminal GCD curves of (a) INS0, (b) INS1, (c) INS2, and (d) INS5 samples; Figure S7: 2T CV curves at (a) higher scan rates (10 mVs\({}^{-1}\) to 100 mVs\({}^{-1}\)) of sample INS0, (b) at scan rate (1 mVs\({}^{-1}\) to 5 mVs\({}^{-1}\)) for INS1, (c) comparative CV spectra of INS0 and INS1 (d) CV curve at different potential window of fabricated SSC device; Figure S8: Leakage current spectra of all prepared samples.  
Conceptualization, N.K., D.M. and S.H.J.; methodology, N.K. and K.M.; software, S.K., D.M. and K.M.; validation, D.M., R.K.M. and S.H.J.; formal analysis, N.K.; investigation, K.M.; resources, J.S. and S.H.J.; data curation, N.K. and D.M.; writing--original draft preparation, N.K. and D.M.; writing--review and editing, D.M. and S.H.J.; visualization, D.M.; supervision, R.K.M., J.S. and S.H.J.; project administration, J.S. and S.H.J.; funding acquisition, J.S. and S.H.J. All authors have read and agreed to the published version of the manuscript.  
This research was funded by Post-Doctor Research Program (2018) through Incheon National University (INU), Incheon, Republic of Korea.  
No new data were created.  
The authors declare no conflict of interest.