Co₃O₄ nanocrystal ink printed on carbon fiber paper as a large-area electrode for electrochemical water splitting

Abstract

A large-area, self-supported Co3O4 nanocrystal/carbon fiber electrode for oxygen and hydrogen evolution reaction was fabricated via thermal decomposition of the [Co(NH3)n](2+)-oleic acid complex and subsequent spray deposition. Due to the exposed active sites and good electrical conductivity, its operate voltage for overall water splitting is nearly the same as commercial Pt/C.

Zn0.76Co0.24S/CoS2 nanowires array for efficient electrochemical splitting of water

“…Note that the Zn-Co-S/TM electrode shows a lower onset overpotential of 316 mV and only requires overpotential of 330 mV to achieve 20 mA cm -2 . This overpotential is lower than that for bifunctional Co-P (~370 mV) [22], NiCo2S4 [26] (~336 mV) and some other non-noble metal OER catalysts in alkaline media, such as CoOx-vacuum (~360 mV) [38], Co3O4 NCs (~360 mV) [39], NiCo LDH (~393 mV)…”

Nanostructured Bifunctional Redox Electrocatalysts

“…Therefore, it is still a great challenge to exploit novel strategies and nanostructures, which feature TMOs with high efficiency toward both HER and OER in alkaline medium. Recently, Du et al proposed the first preparation of large‐area Co 3 O 4 nanocrystals by direct pyrolysis of the [Co(NH 3 ) n ]2 + ‐oleic acid complex and subsequent spray deposition. Although the achieving materials could simultaneously drive both HER and OER in alkaline medium owing to their high electronic conductivity and exposed active sites, the operate voltage for overall water splitting is close to 1.9 V, which is much higher than the theoretical minimum value of 1.23 V. Therefore, there is still a huge potential to improve the electrocatalytic activity of the TMOs.…”

“…owing to their high active sites and favorable stability for HER and OER . Nevertheless, the major drawbacks of these metal compound based electrocatalysts are that they suffer from the higher series resistance as well as the complex fabrication methods, and the bifunctional electrocatalytic properties remains unsatisfactory . Therefore, novel nanostructured materials are required for obtaining high efficiency bifunctional electrocatalysts toward both HER and OER with low cost.…”

A sea anemone-like CuO/Co3O4 composite: an effective catalyst for electrochemical water splitting

“…Recently, the earth-abundant Fe, Co, Ni and Mn oxides have been investigated as potential electrocatalysts for water splitting 6,[8][9][10] . Among them, cobalt oxides are promising bifunctional catalysts for water electrolysis under the same conditions 2,9 .…”

“…Among them, cobalt oxides are promising bifunctional catalysts for water electrolysis under the same conditions 2,9 . The abundant and diversiform d-orbitals endow cobalt oxides with the highly active sites for electrocatalytic water splitting 11,12 .…”