Fabrication of Highly Transparent Substrates from Waste Materials for Electronic Device Applications

In recent years, organic electronics have been explored as a potential paradigm for renewable, transient, and biodegradable systems. In this study, we used fish scales as raw materials for fabricating a biopolymer substrate (BPS) and evaluated its application in an organic metal–insulator–metal capacitor. Evaluation of the morphological and optical properties of BPS revealed an average surface roughness value of 1.19 nm, 90% transmittance in the UV–visible range, and an absorption coefficient of 5.29 cm –1 at 3.5 eV. Fourier transform infrared spectroscopy showed the presence of amide A, amide I, amide II, and amide III bonds in the substrate, and 42° ± 5° was the rollover contact angle. The substrate was dissolved in water within 40 min at room temperature and degraded by more than 90% within 30 days in natural soil. Further, mechanical property analysis showed that the substrate exhibited a flexural strength of 8.33 MPa and a tensile strength of 4 MPa. The capacitance density and leakage current of the Al/bovine serum albumin/Pt/BPS structure are found to be 1.05 fF/μm 2 (1 MHz, 1 V) and 1.15 μA/cm 2 (at 1 V), respectively. The proposed substrate can be used as a cost-efficient, ecofriendly, biocompatible, and transparent charge storage device for transient electronics in the near future.