Porous polyvinyl alcohol/graphene oxide composite film for strain sensing and energy-storage applications

• Published in: Nanotechnology 2022-10, Vol.33 (41), p.415701
• Main Authors: Cui, Xu, Guo, Jia, Araby, Sherif, Abbassi, Fethi, Zhang, Chunyan, Diaby, Abdullatif Lacina, Meng, Qingshi
• Format: Article
• Language: English
• Subjects: graphene oxide; polyvinyl alcohol; porous structure; specific capacitance; strain sensor
• ISSN: 0957-4484; 1361-6528
• DOI: 10.1088/1361-6528/ac7b35

In this study, a flexible porous polyvinyl alcohol (PVA)/graphene oxide (GO) composite film was developed and tested for flexible strain sensing and energy-storage applications. Morphology and mechanical properties were studied; tensile strength and Young’s modulus increased by 225% and 86.88%, respectively, at 0.5 wt% GO. The PVA/GO film possesses exceptional sensing ability to various mechanical strains, such as tension, compression, bending, and torsion. For example, the gauge factor of the PVA/GO film as a tensile-strain sensor was measured as 2.46 (246%). Under compression loads, the PVA/GO composite film showed piezoresistive and capacitive strain-sensing characteristics. Under 5 kPa of compression load, the relative resistance increased by 81% with a 100 msec response time; the relative capacitance increased by 160% with a 120 msec response time. The PVA/GO strain sensor exhibited high durability and reliability over 20 × 10 3 cycles of tensile strain and bending at 3.33 Hz. Moreover, the PVA/GO composite film showed good electrochemical properties due to its porous structure; the maximum capacitance was 124.7 F g −1 at 0.5 wt% GO. After 20 × 10 3 charging–discharging cycles, the capacitance retention rate was 94.45%, representing high stable capacitance performance. The results show that electrically conductive porous PVA nanocomposite films are promising candidates for strain sensing and energy-storage devices.