Ion exchange coupled biomineral self-sacrificial template synthesis of N-enriched porous carbon as robust electrocatalyst for rechargeable Zn-air battery

Sep 2, 2026

To commercialize rechargeable Zn-air batteries, developing metal-free bifunctional electrocatalysts with high activity toward ORR and OER is a key emerging challenge. A prawn-shell-derived N-enriched porous carbon (PSNC) is synthesized using an ion-exchange coupled biomimetic self-sacrificing template strategy. The PSNC provides interconnected macro–meso–micropores for faster charge/mass transfer and abundant pyridinic and graphitic nitrogen to generate catalytic active sites and improve conductivity. In alkaline media, PSNC-0.8 delivers a narrow ΔE of 0.80 V, while Zn-air cells show peak power density of 176.5 mW·cm-2 and only 6.5% efficiency delay after 480 cycles (320 h), offering a simple seafood-waste route for high-performance catalysts.

LanguageEnglish

CategoryGeneral

FormatDOCX

Pages1

AccessFree to download

Introduction

Background and challenges of rechargeable Zn-air batteries

Role of heteroatom-doped porous carbon electrocatalysts

Importance of pore hierarchy and templates

Seafood waste as a precursor and ion-exchange strategy

Ion exchange coupled biomineral self-sacrificial template synthesis of N-enriched porous carbon as robust electrocatalyst for rechargeable Zn-air battery Xiao Xiao, Hui Zhao, Lin-Feng Li, Bing-Liang Qu, Yu-Lian Wu, Yin-Ling Zhu, Bei-Bei Chen*, Gang Pan* X. Xiao, H. Zhao, L.-F. Li, B.-L. Qu, Y.-L. Wu, Y.-L. Zhu School of Chemistry and Environment, Guangdong Ocean University, Zhanjiang 524088, PR China X. Xiao, H. Zhao, L.-F. Li, B.-L. Qu, G. Pan** Research Center for Coastal Environmental Protection and Ecological Resilience, Guangdong Ocean University, Zhanjiang 524088, PR China gang.pan@ntu.ac.uk B.-B. Chen* College of Coastal Agricultural Science, Guangdong Ocean University, Zhanjiang 524088, PR China beibeichenk@outlook.com G. Pan** School of Humanities, York St John University, Lord Mayor's Walk, York, YO31 7EX, United Kingdom Abstract To realize the commercialize of rechargeable Zn-air battery (RZAB), developing metal-free bifunctional electrocatalysts with satisfactory activity for ORR (oxygen reduction reaction) and OER (oxygen evolution reaction) is one of the emerging issues. Herein, a prawn shells-derived N-enriched porous carbon (PSNC) is synthesized via an ion exchange coupled biomimetic self-sacrificing template strategy. The resulting PSNC displays unique functional components, including the interconnected macro-meso-micropores structure to shorten charge and mass transfer pathway, high content of pyridinic and graphitic nitrogen to construct rich catalytic active site and improve conductivity. As electrocatalysts in alkaline condition, the optimized PSNC-0.8 achieves excellent bifunctional catalytic propriety with a narrow potential gap (ΔE) value of 0.80 V. Meanwhile, PSNC-0.8 based RZAB displays a high peak power density of 176.5 mW·cm-2 and considerable cycling durability with a small battery efficiency delay of 6.5% after 480 cycles (320 h). This study enlightens a simple and effective conception to design high performance metal-free bifunctional electrocatalysts from seafood waste. Keywords Rechargeable Zn-air battery (RZAB); Bifunctional electrocatalyst; N-enriched porous carbon; Biomineral self-sacrificial template; Ion exchange 1 Introduction With the increasing demands of energy and environmental sustainability, extensive attention has been focused on the renewable and clean energy [1-5]. Consequently, exploiting the high energy density storage and conversion system has become an inevitable choice [6-11]. Among these systems, rechargeable Zn-air battery (RZAB) displays tremendous application foreground due to various merits, including the eco-friendly, low-cost and high energy density [12-14]. However, the electrochemical performance of RZAB is primarily limited by the sluggish ORR (oxygen reduction reaction) and OER (oxygen evolution reaction) dynamics process [15-17]. The noble metal-based catalysts, such as Pt/C or RuO2, exhibit well ORR or OER catalytic activity [18]. But their large-scale application is still subject to the scarcity nature and insufficient bifunctional catalytic properties. Up to now, the heteroatom-doped porous carbon materials (HPCMs) have been widely regards as the one of the most promising electrocatalysts for RZAB considering their high surface area, environmental acceptability, high electric conductivity and excellent catalytic performance, as well as considerable stability [19]. The theoretical calculations and experimental studies have demonstrated that the heteroatom (e.g. N, S, P) can effectively improve the oxygen catalytic activity of carbon [20-22]. For N-doped carbon, the higher electronegativity of N can change the surface charge distribution of C atoms, which can create rich catalytic active sites and form strong N-C bonds [23]. Specially, the graphitic-N and pyridinic-N (i.e., C-N bonding as active sites) are believed to play a crucial key role in improving ORR and OER process because of the enhanced π bonding [24]. Besides, the porosity of carbon m

FAQs

Why are ORR and OER kinetics the main limitation in rechargeable Zn-air batteries?

Rechargeable Zn-air battery performance is limited by sluggish ORR and OER dynamics, which reduces catalytic efficiency during charging and discharging.

What synthesis strategy is used to prepare the N-enriched porous carbon?

The material is produced from prawn shells via an ion exchange coupled biomineral self-sacrificing template strategy, using EDTA-2Na to regulate CaCO3 content while proteins and chitin provide nitrogen.

How does PSNC-0.8 perform as an electrocatalyst and in a Zn-air cell?

PSNC-0.8 shows excellent bifunctional activity in alkaline conditions with a narrow potential gap (ΔE) of 0.80 V, and the Zn-air battery based on PSNC-0.8 reaches 176.5 mW·cm-2 peak power density with only 6.5% efficiency delay after 480 cycles (320 h).

Sep 2, 2026

Upload by Ethan Miller