Highly Active Mixed-Metal Nanosheet Water Oxidation Catalysts Made by Pulsed-Laser Ablation in Liquids

Abstract

Surfactant-free mixed-metal hydroxide water oxidation nanocatalysts were synthesized by pulsed-laser ablation in liquids. In a series of [Ni-Fe]layered double hydroxides with intercalated nitrate and water, [Ni 1−x Fe x (OH) 2 ](NO 3 ) y (OH) x−y •nH 2 O, higher activity was observed as the amount of Fe decreased to 22%. Addition of Ti 4+ and La 3+ ions further enhanced electrocatalysis, with a lowest overpotential of 260 mV at 10 mA cm −2 . Electrocatalytic water oxidation activity increased with the relative proportion of a 405.1 eV N 1s (XPS binding energy) species in the nanosheets.

Recent Progress on Layered Double Hydroxides and Their Derivatives for Electrocatalytic Water Splitting

“…Currently, transition‐metal (Fe, Co, Ni, Mn, and Mo)‐based catalysts including metal oxides,23, 24, 25, 26, 27, 28, 29, 30 hydroxides,31, 32, 33, 34, 35 phosphides,36, 37, 38, 39, 40, 41, 42 sulfides,43, 44, 45, 46, 47, 48 selenides,49, 50, 51, 52, 53, 54 and nitrides55, 56, 57, 58, 59, 60, 61, 62 have been highlighted as the most promising candidates of OER and HER electrocatalysts. Especially, layered double hydroxides (LDHs)63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85 and their derivatives (metal hydroxides, oxyhydroxides, oxides, bimetal nitrides, phosphides, sulfides, and selenides)86, 87, 88, 89, 90, 91, 92…”

Influence of iron doping on tetravalent nickel content in catalytic oxygen evolving films

“…The behavior of Fe-doped Ni (Fe:Ni) oxide films under basic conditions (1 M KOH) has been revisited (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) and in this recent body of work, the role of Fe in these films has come under debate. X-ray absorption spectra of Fe:Ni oxide films supported by computational studies have led to the contention that Fe 3+ species are the active sites for water oxidation (13).…”

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).…”