Engineering Electronic Structure of Nitrogen-Carbon Sites by sp3 -Hybridized Carbon and Incorporating Chlorine to Boost Oxygen Reduction Activity.
Angew Chem Int Ed Engl
; 63(1): e202316314, 2024 Jan 02.
Article
en En
| MEDLINE
| ID: mdl-38032121
ABSTRACT
Development of efficient and easy-to-prepare low-cost oxygen reaction electrocatalysts is essential for widespread application of rechargeable Zn-air batteries (ZABs). Herein, we mixed NaCl and ZIF-8 by simple physical milling and pyrolysis to obtain a metal-free porous electrocatalyst doped with Cl (mf-pClNC). The mf-pClNC electrocatalyst exhibits a good oxygen reduction reaction (ORR) activity (E1/2 =0.91â
V vs. RHE) and high stability in alkaline electrolyte, exceeding most of the reported transition metal carbon-based electrocatalysts and being comparable to commercial Pt/C electrocatalysts. Likewise, the mf-pClNC electrocatalyst also shows state-of-the-art ORR activity and stability in acidic electrolyte. From experimental and theoretical calculations, the better ORR activity is most likely originated from the fact that the introduced Cl promotes the increase of sp3 -hybridized carbon, while the sp3 -hybridized carbon and Cl together modify the electronic structure of the N-adjacent carbons, as the active sites, while NaCl molten-salt etching provides abundant paths for the transport of electrons/protons. Furthermore, the liquid rechargeable ZAB using the mf-pClNC electrocatalyst as the cathode shows a fulfilling performance with a peak power density of 276.88â
mW cm-2 . Flexible quasi-solid-state rechargeable ZAB constructed with the mf-pClNC electrocatalyst as the cathode exhibits an exciting performance both at low, high and room temperatures.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Año:
2024
Tipo del documento:
Article
País de afiliación:
China