Green synthesis of ZnO nanoparticles decorated on polyindole functionalized-MCNTs and used as anode material for enzymatic biofuel cell applications

Inamuddin Inamuddin,Nimra Shakeel,Suvardhan Kanchi,Mohd Imran Ahamed,Heba Abbas Kashmery

doi:10.1038/s41598-020-61831-4

Abstract

Presently, one of the most important aspects for the development of enzymatic biofuel cells (EBFCs) is to synthesize the novel electrode materials that possess high current density, low open-circuit voltage (OCV) and long-term stability. To achieve the above attributes, lots of new strategies are being used by the researchers for the development of advanced materials. Nowadays, nanomaterials and nanocomposites are the promising material that has been utilized as effective electrode material in solar cells, supercapacitors and biofuel cells application. Herein, we account for a novel electrocatalyst as electrode material that comprised ZnO nanoparticles decorated on the surface of polyindole (PIn)-multi-walled carbon nanotube (MWCNT), for the immobilization of glucose oxidase (GOx) enzyme and mediator (Ferritin). The PIn-MWCNT scaffold is prepared via in situ chemical oxidative polymerization of indole on the surface of MWCNT and assessed by myriad techniques. The micrograph of scanning electron microscopy (SEM) designated the interconnected morphology of MWCNTs in the polymer matrix. X-ray diffraction spectroscopy (XRD) and Fourier transform infrared spectroscopy (FTIR), confirm the crystallinity and different functional groups available in the synthesized material, respectively. The electrochemical assessment demonstrates that the ZnO/PIn-MWCNT/Frt/GOx nanobiocatalyst exhibits much higher electrocatalytic activity towards the oxidation of glucose with a maximum current density of 4.9 mA cm−2 by consuming 50 mM glucose concentration in phosphate buffer saline (PBS) (pH 7.4) as the testing solution by applying 100 mVs−1 scan rates. The outcomes reflect that the as-prepared ZnO/PIn-MWCNTs/Frt/GOx biocomposite is a promising bioanode for the development of EBFCs.

Highlights

One of the most important aspects for the development of enzymatic biofuel cells (EBFCs) is to synthesize the novel electrode materials that possess high current density, low open-circuit voltage (OCV) and long-term stability
It is to be noted that the spectrum of ZnO/PInMWCNTs nanocomposite given in Fig. 3(d) manifested all the bands as found in the individual spectrum with less peak intensity
The ternary nanocomposite comprising of PIn, multi-walled carbon nanotube (MWCNT), and zinc oxide nanoparticles (ZnO NPs) was successfully synthesized via the in-situ chemical oxidative polymerization route

Summary

Introduction

One of the most important aspects for the development of enzymatic biofuel cells (EBFCs) is to synthesize the novel electrode materials that possess high current density, low open-circuit voltage (OCV) and long-term stability. To the best of our knowledge, we inculcate the characteristics of individual component at one platform that reflect the synergistic properties which are favorable in selecting their counterparts and to the best of our vision this is the first attempt that utilized ZnO-PIn doped CNTs based nanocomposite as a supporting material in developing bioanode for the wiring of enzyme in EBFCs application.

Results

Conclusion