Molecule-level graphdiyne coordinated transition metals as a new class of bifunctional electrocatalysts for oxygen reduction and oxygen evolution reactions

Abstract

Graphdiyne (GDY) could provide a unique platform for synthesizing uniform single-atom catalysts (SACs) with high catalytic activity toward oxygen reduction (ORR) and oxygen evolution (OER) reactions.

Bifunctional catalytic activity of Zn1−xFexO toward the OER/ORR: seeking an optimal stoichiometry

“…1,4,7 The ORR take place during discharging, oxidizing the metal at the counter electrode, while the OER occurs during charging, oxidizing the metal at the counter electrode. 4,8 ORR involves numerous consecutive steps, including oxygen diffusion from the atmosphere to the catalyst surface, oxygen adsorption on the catalyst surface, and electron transfer from the anode to the oxygen molecules on the cathode surface to form the discharge product. 9 To be highly efficient, energy storage devices, or metalair batteries required fast ORR, also, highly-reversible to regenerate oxygen molecules during the charging process where OER takes place.…”

Graphynes: ideal supports of single atoms for electrochemical energy conversion

“…In 2019, Ma et al designed a series of GDY-supported TM SACs for the OER. 144 The positive binding energy (E b ) and suitable energy difference (DE b ) between E b and cohesive energy (D-F) the free energy diagrams of Ni@GDY, Pd@GDY, and Pt@GDY in alkaline media for the OER; (G-I) the optimized adsorption structures of OOH, O and OH on Ni@GDY, Pd@GDY and Pt@GDY monolayers (the gray, red, and white balls represent C, O, and H atoms, respectively); (J-L) the top view and side view of the charge density difference of O/Ni@GDY, O/Pd@GDY, and O/Pt@GDY; (M-O) the spin density of O/Ni@GDY, O/Pd@GDY, and O/Pt@GDY (yellow and blue regions represent charge accumulation and depletion or spin-up and spin-down states and the isosurface level is 0.02 e ÅÀ3 ). Reproduced with permission.…”

Recent developments in the use of single-atom catalysts for water splitting

“…It is well known that each element has its own chemical properties. When the single metal atom is considered to be the active site, different single metal atoms featured with different atomic structures may demonstrate different activities [167][168][169][170][171][172]. Duan et al [102] reported an approach using graphene oxide to fabricate atomic 3d metal atoms embedded in nitrogen-doped holey graphene frameworks (M-NHGFs).…”