Search

Efficient and noble metal-free electrocatalyst could enhance conceivably fuel cell's affordable commercialization. In this esteem, we developed CoO embedded N-doped CNTs from zeolitic imidazolate framework (ZIF-12) by single step inert atmosphere calcination, to be used as oxygen reduction reaction (ORR) electrocatalyst. In the electrochemical studies performed, the CoO/N-CNTs has demonstrated an onset potential of 0.83 V vs. RHE, very close to the commercial Pt catalyst value, electron transfer number of 3.5 which approaches the theoretical value of 4 and current density of 3.35 mA cm − 2 at 2500 rmp. The excellent activity of the electrocatalyst is to be attributed to its waved-tubular structure casing CoO particles and to its high surface area as it was proved by TEM and gas adsorption analysis. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The dearth of an efficient, robust, abundant and cost-effective water oxidation catalyst is debatably the major hurdle for the technological advancement of artificial photosynthesis devices. Herein, a three dimensional (3D) cobalt-based coordination polymer {[Co 3 (pyz)(fa) 3 (dmso) 2 ]·2H 2 O} n , (1) (pyz = pyrazine, fa = fumarate, dmso = dimethyl sulfoxide) has been synthesized and demonstrated to act as an efficient electrocatalyst towards water oxidation at neutral pH. Compound 1 displays a stair-like arrangement parallel to the b -axis, with the cobalt clusters arranged in a zigzag fashion, and contains small, honeycomb-like channels parallel to the c -axis. Compound 1 shows a remarkable activity for water oxidation and attains a current density of 1 mA.cm−2 at low overpotential (η = 257 mV) with a Tafel slope value of 80.5 mV.dec−1. This high performance of 1 in catalysing the water oxidation reaction is attributed to its unique 3-D architecture. The results of electrochemical investigations, including long-term and controlled potential electrolysis, are anticipated to guide the forthcoming advancement in creating efficient, cheap and noble metal (Pt/Ru/Ir) free catalysts for the water oxidation reaction. [ABSTRACT FROM AUTHOR]