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The utilization of manganese oxides/oxyhydroxides as efficient supercapacitor electrode materials is limited by their cyclic stability and thus restricted for practical applications. One attractive approach for improving their stable electrochemical performance is to form a hybrid with suitable support materials. Herein, we describe the fabrication of manganese oxide/oxyhydroxide nanoparticle (MONP)embedded deoxyribonucleic acid (DNA) scaffolds using a simple magnetic stirring and drop-casting method. The physical and chemical property measurements provided information regarding the interactions of the MONPs with the DNA in the scaffolds. Further, these materials' electrical properties were studied by looking at the MONP concentration-dependent current characteristics. Our testing shows a monotonic increase in current with increasing MONP concentration. The supercapacitance activity of MONP-embedded DNA scaffolds with various MONP concentrations was explored using cyclic voltammetry (CV) and galvanostatic charge−discharge (GCD) measurements. From the electrochemical studies conducted, it was found that the supercapacitance values achieved while using scaffolds decreased up to a certain concentration of MONPs and then increased thereafter. The DNA scaffolds with a 0.5 weight percentage (wt %) of MONPs achieved ∼60% of the specific capacitance value of pristine MONPs. Long-term cyclic stability studies showed that using pristine MONPs, DNA, and MONP-embedded DNA scaffolds led to the supercapacitor samples retaining 71.9, 104.6, and 108.8%, respectively, of their initial specific capacitance values after 10 000 cycles at a current density of 5 A g −1 . The excellent cyclic stability of the devices with DNAbased scaffolds proves that DNA acts as a strong support material and helps to solve one of the major drawbacks of manganese-based supercapacitance electrode materials. This unique approach of utilizing DNA as a stable support material can be extended to numerous other materials to achieve better cyclic stability and can be used for a wide range of electrochemical applications.

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The development of flexible DNA thin films embedded with diverse functional nanomaterials might be beneficial for electronic devices and biosensors. In this work, we fabricated two different methods of electrodes (i.e., metal paste spotted electrodes and metal layer electrodes) on flexible drug- and dye-embedded DNA thin films to examine the electrical and capacitance properties for conduction and energy storage, respectively. Enhanced current and reduced capacitance of drug-embedded DNA thin films compared to pristine DNA with Ag paste electrodes were observed due to the intrinsic characteristics of the drugs. We introduced the e-beam deposition process for fabricating relatively large area metal (such as Au and Al) coated electrodes, which ensures the creation of metal layers on both sides of the flexible thin films while improving metal contact. There was a significant current increase in DNA thin films with metal layer electrodes compared to DNA thin films with Ag paste electrodes. Furthermore, capacitances measured from Au/Dg/Au and Al/Dg/Al capacitors were relatively more stable than Ag paste DNA thin films. The physical properties of our samples might easily be controlled by manipulating functional nanomaterials in DNA thin films and various types of metal layer electrodes. Our self-supporting DNA thin films with integrated nanomaterials and durable metal layer electrodes might be employed in flexible electronic devices such as nanogenerators, skin electronics, and biosensors in the future.

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