Dynamic stability of active sites in hydr(oxy)oxides for the oxygen evolution reaction

Dual Role of Silver Moieties Coupled with Ordered Mesoporous Cobalt Oxide towards Electrocatalytic Oxygen Evolution Reaction

“…One of possible reasons is the formation of active Fe 4+ species which can serve as dynamically active sites at the catalyst/electrolyte interface with balanced binding energies of oxygen intermediates. [54,63,64] Another possible reason is the presence of Fe 3+ stimulating the oxidation of M 2+ (M:Coand Ni)toM 3+/4+ instead of its further oxidation to Fe 4+ . [56,57,65] As seen in Figure S23, the Ag 2 Oitself showed avery poor OER activity even in the presence of an excess amount of iron impurity.Therefore,itdoes make sense to postulate either (i) the interaction between Ag 2 Oa dsorbed by iron impurities and Co 3 O 4 or (ii)t he formation of new active species consisting of cobalt-silver-iron synergistically facilitated the OER kinetics.R esultantly,m uch higher current density at 1.7 V RHE was achieved on the activated Co 8 Ag oxide (211 mA cm À2 ), more than twice of that of Co 3 O 4 (102 mA cm À2 ).…”

Dual Role of Silver Moieties Coupled with Ordered Mesoporous Cobalt Oxide towards Electrocatalytic Oxygen Evolution Reaction

“…One of possible reasons is the formation of active Fe 4+ species which can serve as dynamically active sites at the catalyst/electrolyte interface with balanced binding energies of oxygen intermediates. [54,63,64] Another possible reason is the presence of Fe 3+ stimulating the oxidation of M 2+ (M:Coand Ni)toM 3+/4+ instead of its further oxidation to Fe 4+ . [56,57,65] As seen in Figure S23, the Ag 2 Oitself showed avery poor OER activity even in the presence of an excess amount of iron impurity.Therefore,itdoes make sense to postulate either (i)…”

Electrocatalysis as the Nexus for Sustainable Renewable Energy: The Gordian Knot of Activity, Stability, and Selectivity

“…The reactions at this interface are sensitive to surface electronic and geometric properties of the electrode, electrolyte properties (including pH value, concentration, ionic strength, and the nature of anions and cations), and the electric field strength to mention a few. [3,4] An ideally designed electrochemical interface, which is the goal of electrocatalysis, would make it possible to exploit the excess energy harnessed from renewable sources to convert molecules at our everyday disposal, H 2 O, N 2 , and CO 2 , into limitless energy carriers for energy applications from light portable systems and electromobility to mini-gridand grid-scale energy storage, [4][5][6] as well as industrial chemicals. [5,7] For example, reversible interconversion of H 2 O into H 2 in an electrolyzer, and the recombination of H 2 and O 2 in a fuel cell to reform H 2 O, releasing useful energy, offers the prospect of a virtually limitless supply of clean energy and is the essence of the hydrogen economy.…”