Peach Gum‐Derived S,N Co‐Doped Nanoporous Carbon Coupled with Layered Double (Ni, Fe) Hydroxide for Efficient Bifunctional Oxygen Electrocatalysis in Zn‐Air Batteries

Abstract

Low‐cost and high activity bifunctional oxygen electrocatalysts are at the heart of developing advanced rechargeable Zn‐air batteries (ZABs), but the challenges are great. Herein, a highly efficient hybrid catalyst, consisting of S, N co‐doped nanoporous carbon (SNC) coupled with in‐situ growth layered double (Ni, Fe) hydroxide (LDH), was derived from the biomass peach gum by a series of treatments, including hydrothermal carbonization, alkali activation, S/N co‐doping and metal‐coprecipitation process. Benefiting from the coexistence of active sites for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), the hybrid (NiFe‐LDH/SNC) reveals excellent bifunctional electrocatalytic activity with a small ΔE of 794 mV. Furthermore, as the cathode bifunctional catalyst for ZAB, the battery with NiFe‐LDH/SNC displays a large open‐circuit voltage of 1.36 V, a high power density/specific capacity of 100 mW cm−2/816 mAh gZn−1, and superior cycling durability up to 500 h at a charge/recharge current density of 2 mA cm−2, indicating its great application potential in the rechargeable metal‐air batteries.

N‐doped Nanocarbon Inserted NiCo‐LDH Nanoplates on NF with High OER/ORR Performances for Zinc‐Air Battery

“…In addition, at 10 mA cm −2 , the capacity of NiCo‐LDH/NCM@NF‐based ZABs (685 mAh g −1 ) is superior to Pt/C+IrO 2 ‐based ZABs (599 mAh g −1 , Figure 8c). It is noted that, the reported hybrid catalyst composed of sulfur, nitrogen co‐doped nanoporous carbon (SNC) coupled with Ni, Fe LDH displays an OCV of 1.36 V, with a power density of 100 mW cm −2 [53] . The ZABs based on CoFe‐LDH@FeCo NPs−N‐CNTs catalyst deliver the power density of 116 mW cm −2 [54] .…”

“…It is noted that, the reported hybrid catalyst composed of sulfur, nitrogen co-doped nanoporous carbon (SNC) coupled with Ni, Fe LDH displays an OCV of 1.36 V, with a power density of 100 mW cm À 2 . [53] The ZABs based on CoFe-LDH@FeCo NPsÀ N-CNTs catalyst deliver the power density of 116 mW cm À 2 . [54] Meanwhile, the NiCo-LDH/NCM@NFbased ZAB also has high energy density as the reported Co, Nibased ZAB batteries listed in Table S3.…”

Research Progress of Bifunctional Oxygen Reactive Electrocatalysts for Zinc–Air Batteries

“…Wang et al prepared a NiFe LDH/SNC bifunctional catalyst based on the recombination of sulfur and nitrogen co-doped porous carbon with bimetal (Ni and Fe) hydroxide (LDH), where the ORR half-wave potential was 0.736 V, and the overpotential for OER at 10 mAcm −2 was as low as 298 mV with ΔE of 794 mV. The open-circuit voltage of the ZAB cathode assembly battery reached 1.36 V, and this excellent performance is attributed to the coupling action between the components [ 146 ]. Although NiFe-LDH exhibits an excellent OER performance, the poor stability limits its further application.…”