DNA-Modified Cobalt Tungsten Oxide Hydroxide Hydrate Nanochains as an Effective Electrocatalyst with Amplified CO Tolerance during Methanol Oxidation

Sangeetha Kumaravel; Mohanapriya Subramanian; Kannimuthu Karthick; Arunkumar Sakthivel; Subrata Kundu; Subbiah Alwarappan

doi:10.1021/acsomega.1c02515

DNA-Modified Cobalt Tungsten Oxide Hydroxide Hydrate Nanochains as an Effective Electrocatalyst with Amplified CO Tolerance during Methanol Oxidation

ACS Omega. 2021 Jul 13;6(29):19162-19169. doi: 10.1021/acsomega.1c02515. eCollection 2021 Jul 27.

Authors

Sangeetha Kumaravel^{1

2}, Mohanapriya Subramanian¹, Kannimuthu Karthick^{1

2}, Arunkumar Sakthivel^{1

2}, Subrata Kundu^{1

2}, Subbiah Alwarappan^{1

2}

Affiliations

¹ CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630003, India.
² Academy of Scientific and Innovative Research (AcSIR), CSIR- Human Resource Development Centre, (CSIR-HRDC) Campus, Postal Staff College Area, Sector 19, Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh 201002, India.

Abstract

Direct methanol fuel cell technology implementation mainly depends on the development of non-platinum catalysts with good CO tolerance. Among the widely studied transition-metal catalysts, cobalt oxide with distinctively higher catalytic efficiency is highly desirable. Here, we have evolved a simple method of synthesizing cobalt tungsten oxide hydroxide hydrate nanowires with DNA (CTOOH/DNA) and without incorporating DNA (CTOOH) by microwave irradiation and subsequently employed them as electrocatalysts for methanol oxidation. Following this, we examined the influence of incorporating DNA into CTOOH by cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy. The enhanced electrochemical surface area of CTOOH offered readily available electroactive sites and resulted in a higher oxidation current at a lower onset potential for methanol oxidation. On the other hand, CTOOH/DNA exhibited improved CO tolerance and it was evident from the chronoamperometric studies. Herein, we noticed only a 2.5 and 1.8% drop at CTOOH- and CTOOH/DNA-modified electrodes, respectively, after 30 min. Overall, from the results, it was evident that the presence of DNA in CTOOH played an important role in the rapid removal of adsorbed intermediates and regenerated active catalyst centers possibly by creating high density surface defects around the nanochains than bare CTOOH.