Hierarchically Porous Heteroatoms‐doped Vesica‐like Carbons as Highly Efficient Bifunctional Electrocatalysts for Zn‐air Batteries

Abstract

Developing highly efficient and cost‐effective electrocatalysts to boost the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is vital for the sustainable energy systems. The nitrogen and phosphorus codoped vesica‐like carbons with hierarchical nanoporous structure are synthesized through an efficient self‐polymerization strategy with the template of g‐C3N4 monolith. Featuring sufficient heteroatom‐doping, well‐developed porous hierarchy, and high electrochemical surface area, the fabricated carbon materials exhibit considerable activity and robust stability in both electrocatalyzing ORR and OER, in competition with the precious metal electrocatalysts, which are thus capable of using as air cathode catalysts for rechargeable Zn‐air batteries, affording large discharge current density and impressive operation stability.

Aqueous Rechargeable Zn–N2 Battery Assembled by Bifunctional Cobalt Phosphate Nanocrystals-Loaded Carbon Nanosheets for Simultaneous NH3 Production and Power Generation

“…The target elements of C, N, O, P, and Co are confirmed by the XPS survey scan (SI Figure S8a) of CoPi/NPCS. In C 1s spectra (SI Figure S8b), the contributions, including sp 2 -hybridized graphitic C, N-sp 2 C, N-sp 3 C, and π → π*, are detected at the bonding energies of 284.8, 286.3, 288.1, and 290.3 eV, respectively . For N 1s spectra (SI Figure S8c), the pyridinic N (398.4 eV), pyrrolic N (399.4 eV), graphitic N (400.8 eV), and oxidized N (402.8 eV) are presented. , As to the peak fitting of the P 2p spectra (SI Figure S8d), the double contributions centered at 128.7 and 130.0 eV are ascribed to the P 2p 3/2 and P 2p 1/2 , and the dominant peak at 132.8 eV is assigned to the association of transition metals with phosphate groups, while the peak located at 134.1 eV is the P–C bonds inserted into carbon skeleton .…”

Melamine‐Induced N,S‐Codoped Hierarchically Porous Carbon Nanosheets for Enhanced Electrocatalytic Oxygen Reduction

“…As depicted in Figure a, the XPS full spectrum of NS‐CS reveals the existence of C, N, O and S elements, and the atomic percentage of N and S elements was 5.62% and 8.17%. The C 1s spectra (Figure b) can be deconvoluted into five peaks at 284.8 eV (C=C‐C), 285.5 eV (C=N), 286.4 eV (C−N/C−O), 287.3 eV (C=O) and 289.2 eV (C=O‐OH) . The N 1s spectra (Figure c) can be fitted into three peaks including pyridinic N (398.5 eV), graphitic N (401.1 eV), and pyridinic‐N‐oxides (403.7 eV) species .…”

Advances in Zeolite Imidazolate Frameworks (ZIFs) Derived Bifunctional Oxygen Electrocatalysts and Their Application in Zinc–Air Batteries

“…Carbon‐based materials featuring flexible physicochemical and structural properties, high conductivity, low cost, and abundance are considered among the front‐runners to substitute the noble metals as reversible oxygen electrocatalysts. [ 131 ] In contrast to metal‐loaded catalysts, metal‐free carbon catalysts help to avoid the issues of leaching and particle agglomeration, thereby exhibit better long‐term stability. For the development of carbon‐based materials, numerous factors such as effective reactants (OH ‐ and O 2 ) transport to active sites and optimum amount of adsorption energy between reaction intermediates and reactants should be taken into account.…”