Superstructured Carbon with Enhanced Kinetics for Zinc‐Air Battery and Self‐Powered Overall Water Splitting

Abstract

The present study proposes a novel engineering concept for the customization of functionality and construction of superstructure to fabricate 2D monolayered N‐doped carbon superstructure electrocatalysts decorated with Co single atoms or Co2P nanoparticles derived from 2D bimetallic ZnCo‐ZIF superstructure precursors. The hierarchically porous carbon superstructure maximizes the exposure of accessible active sites, enhances electron/mass transport efficiency, and accelerates reaction kinetics simultaneously. Consequently, the Co single atoms embedded N‐doped carbon superstructure (Co‐NCS) exhibits remarkable catalytic activity toward oxygen reduction reaction, achieving a half‐wave potential of 0.886 V versus RHE. Additionally, the Co2P nanoparticles embedded N‐doped carbon superstructure (Co2P‐NCS) demonstrates high activity for both oxygen evolution reaction and hydrogen evolution reaction, delivering low overpotentials of 292 mV at 10 mA cm−2 and 193 mV at 10 mA cm−2 respectively. Impressively, when employed in an assembled rechargeable Zn‐air battery, the as‐prepared 2D carbon superstructure electrocatalysts exhibit exceptional performance with a peak power density of 219 mW cm−2 and a minimal charge/discharge voltage gap of only 1.16 V at 100 mA cm−2. Moreover, the cell voltage required to drive an overall water‐splitting electrolyzer at a current density of 10 mA cm−2 is merely 1.69 V using these catalysts as electrodes.

Mapping current high-entropy materials for water electrolysis: from noble metal to transition metal

“…It means that simultaneously using excellent electrocatalysts for OER and HER can achieve high-efficiency hydrogen production through water splitting. 23–28 Currently, precious metals such as platinum, ruthenium and iridium are ideal catalysts to effectively reduce the overpotential for either HER or OER. 29–33 In recent years, many research scholars have been exploring efficient materials to catalyze HER and OER to improve the efficiency of hydrogen preparation.…”

Microenvironment Tailoring of NiCo Alloys Coupled with FePc as Efficient Bifunctional Catalysts for High-Rate Zn-Air Batteries

“…Currently, rechargeable Zn-air batteries have a broad application prospect in the new generation of renewable energy conversion due to their advantages of high specific capacity, low cost, high security, and being pollution-free. , However, the commercial development of Zn-air batteries faces the major challenge of the slow kinetics of the two main reactions, oxygen reduction reaction (ORR) and oxygen precipitation reaction (OER), on the air cathode. − Therefore, an ideal bifunctional catalyst needs to be designed to reduce the overpotential and accelerate the kinetic process. Pt-based and Ru-based catalysts based on precious metals are the best catalysts for catalytic activity, but their limited resources, expensive nature, and poor corrosion resistance inevitably restrict the commercialization of Zn-air batteries. − …”