Water Oxidation Electrocatalyzed by an Efficient Mn₃O₄/CoSe₂Nanocomposite

Abstract

The design of efficient, cheap, and abundant oxygen evolution reaction (OER) catalysts is crucial to the development of sustainable energy sources for powering fuel cells. We describe here a novel Mn(3)O(4)/CoSe(2) hybrid which could be a promising candidate for such electrocatalysts. Possibly due to the synergetic chemical coupling effects between Mn(3)O(4) and CoSe(2), the constructed hybrid displayed superior OER catalytic performance relative to its parent CoSe(2)/DETA nanobelts. Notably, such earth-abundant cobalt (Co)-based catalyst afforded a current density of 10 mA cm(-2) at a small overpotential of ~0.45 V and a small Tafel slope down to 49 mV/decade, comparable to the best performance of the well-investigated cobalt oxides. Moreover, this Mn(3)O(4)/CoSe(2) hybrid shows good stability in 0.1 M KOH electrolyte, which is highly required to a promising OER electrocatalyst.

Nitrogen-doped carbon nanomaterials as non-metal electrocatalysts for water oxidation

“…Consequently, researchers have attempted to biomimic natural compounds, such as hybrids of CaMn 2 O 4 and Mn 3 O 4 /CoSe 2 , to obtain efficient OER electrocatalysts [13][14][15] . However, a nanocomposite of Mn 3 O 4 /CoSe 2 required an overpotential of approximately 0.45 V in potassium hydroxide (KOH) solution (pH 13) to achieve a current density of 10 mA cm À 2 (current density based on geometric surface area (GSA)) 15 .…”

Enhancing Oxygen Evolution Reaction at High Current Densities on Amorphous‐Like Ni–Fe–S Ultrathin Nanosheets via Oxygen Incorporation and Electrochemical Tuning

“…Transition‐metal (e.g., Ni, Co, Fe) based materials, including oxides,5 (oxy)hydroxides,[[qv: 3a,6]] selenides,7 sulfides,8 and nitrides,9 have been extensively investigated as promising candidates of high‐performance catalysts for OER. Despite these impressive progress in OER activity, it is still a long way from industrial applications with requirement of very large current densities at low overpotentials.…”

Paper‐Based N‐Doped Carbon Films for Enhanced Oxygen Evolution Electrocatalysis

“…Besides enthusiastic efforts to search for new electrocatalysts to facilitate these processes, numerous studies are also devoted to making better use of the existing electrocatalysts for achieving optimal properties 2, 8, 9, 10, 11. Common strategies for enhancing the performances of electrocatalysts include either optimization of their chemical compositions or micro/nanostructures 2, 8, 9, 10, 11. Nevertheless, these methods require complicated procedures with long‐time operation and the catalytic performances remain unsatisfactory.…”

“…OER is a critical step in water splitting and metal–air batteries, which involves the oxidation of water into oxygen molecules in alkaline (4OH − → 2H 2 O + O 2 + 4e − ) or neutral/acidic solutions (2H 2 O → 4H + + O 2 + 4e − ) 2, 3, 8, 9. Because of its sluggish kinetics, OER usually proceeds on various electrocatalysts such as noble metal (irrinium oxide IrO 2 and ruthinium oxide RuO 2 ),14, 15 nonprecious metal (manganese dioxide MnO 2 ,16 cobalt oxide Co 3 O 4 ,17 and perovskite Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3–δ ),3 and nonmetal materials (nitrogen‐doped graphite18 and carbon nanotube11).…”