TY - JOUR
T1 - Self-Assembled Molecular Hybrids of CoS-DNA for Enhanced Water Oxidation with Low Cobalt Content
AU - Karthick, Kannimuthu
AU - Anantharaj, Sengeni
AU - Karthik, Pitchiah E.
AU - Subramanian, Balasubramanian
AU - Kundu, Subrata
N1 - Funding Information:
We wish to acknowledge CSIR-CECRI and Dr. Vijayamohan K. Pillai, Director, CSIR-CECRI, for their continuous support and encouragement. K.K. wishes to acknowledge UGC for a JRF award. S.A. wishes to acknowledge CSIR for an SRF award. P.E.K. gratefully acknowledges SERB, New Delhi for NPDF. The contributions from Central Instrumentation Facility (CIF) and help from Mr. A. Rathish Kumar (TEM in-charge, CIF) are greatly appreciated.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/6/5
Y1 - 2017/6/5
N2 - Water oxidation in alkaline medium was efficiently catalyzed by the self-assembled molecular hybrids of CoS-DNA that had 20 times lower Co loading than the commonly used loading. The morphological outcome was directed by varying the molar ratio of metal precursor Co(Ac)2 and DNA and three different sets of CoS-DNA molecular hybrids, viz. CoS-DNA(0.036), CoS-DNA(0.06), and CoS-DNA(0.084) were prepared. These morphologically distinct hybrids had shown similar electrocatalytic behavior, because of the fact that they all contained the same cobalt content. The CoS-DNA(0.036), CoS-DNA(0.06), and CoS-DNA(0.084) required very low overpotentials of 350, 364, and 373 mV at a current density of 10 mA cm-2 (1 M KOH), respectively. The advantages of lower overpotential, lower Tafel slope (42.7 mV dec-1), high Faradaic efficiency (90.28%), high stability and reproducibility after all, with a lower cobalt loading, have certainly shown the worth of these molecular hybrids in large-scale water oxidation. Moreover, since DNA itself a good binder, CoS-DNA molecular hybrids were directly casted on substrate electrodes and used after drying. It also showed minimum intrinsic resistance as DNA is a good ionic and electronic conductor. Besides, the present method may also be extended for the preparation of other active electrocatalysts for water splitting.
AB - Water oxidation in alkaline medium was efficiently catalyzed by the self-assembled molecular hybrids of CoS-DNA that had 20 times lower Co loading than the commonly used loading. The morphological outcome was directed by varying the molar ratio of metal precursor Co(Ac)2 and DNA and three different sets of CoS-DNA molecular hybrids, viz. CoS-DNA(0.036), CoS-DNA(0.06), and CoS-DNA(0.084) were prepared. These morphologically distinct hybrids had shown similar electrocatalytic behavior, because of the fact that they all contained the same cobalt content. The CoS-DNA(0.036), CoS-DNA(0.06), and CoS-DNA(0.084) required very low overpotentials of 350, 364, and 373 mV at a current density of 10 mA cm-2 (1 M KOH), respectively. The advantages of lower overpotential, lower Tafel slope (42.7 mV dec-1), high Faradaic efficiency (90.28%), high stability and reproducibility after all, with a lower cobalt loading, have certainly shown the worth of these molecular hybrids in large-scale water oxidation. Moreover, since DNA itself a good binder, CoS-DNA molecular hybrids were directly casted on substrate electrodes and used after drying. It also showed minimum intrinsic resistance as DNA is a good ionic and electronic conductor. Besides, the present method may also be extended for the preparation of other active electrocatalysts for water splitting.
UR - http://www.scopus.com/inward/record.url?scp=85020268056&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85020268056&partnerID=8YFLogxK
U2 - 10.1021/acs.inorgchem.7b00855
DO - 10.1021/acs.inorgchem.7b00855
M3 - Article
C2 - 28493681
AN - SCOPUS:85020268056
SN - 0020-1669
VL - 56
SP - 6734
EP - 6745
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 11
ER -
