Tunable nitrogen crafted 2D-graphene nano-hybrid from industrial expansive and ecological approach as robust cathode microporous layer to improve performance of a direct methanol fuel cell  

作　　者：BALAKRISHNAN Prabhuraj GUAN Li LIU HuiYuan LEUNG PuiKi SHAH Akeel XING Lei SU HuaNeng XU Qian 

机构地区：[1]Institute for Energy Research,Jiangsu University,Zhenjiang 212013,China [2]School of Energy and Power Engineering,Chongqing University,Chongqing 400030,China [3]Department of Chemical Process Engineering,University of Surrey,Guildford GU27XH,UK

出　　处：《Science China(Technological Sciences)》2023年第9期2669-2680,共12页中国科学（技术科学英文版）

基　　金：supported by China Postdoctoral Science Foundation(Grant No.2019M661749);Six-Talent-Peaks Project in Jiangsu Province(Grant No.2016-XNY-015);the High-Tech Key Laboratory of Zhenjiang City(Grant No.SS2018002);Priority Academic Program Development(PAPD) of Jiangsu Higher Education Institutions。

摘　　要：In this work, the excess water-stagnation issue in the high current region in direct methanol fuel cells(DMFCs) is resolved by using atomic precision modulated nitrogen-crafted graphene(NG) in the cathode microporous layer by utilizing simplistic,industrial-expansive and ecological strategy. Few-layer 2D-graphene(~2–5 nm thickness) is prepared by bath sonication approach from abundant feedstock-graphite and is treated with nitric acid to yield 1.8 wt.% uniformly dispersed nitrogen containing NG. Specifically, 1:4 weight ratio NG:carbon-black(CB) hybrid architecture, displays 0.252 V in 370 mA cm^(-2) with the peak power density of 93.4 mW cm^(-2), improving cell power density by 45.6% compared with standard one at 60℃ and 1 mol/L methanol/oxygen conditions at ultra-low catalyst loadings and displaying exceptional stability. Atomic insights into NG reveal that interplay between bonding configurations, altered hydrophobic/hydrophilic porosity of graphene(10.6% less wettability from contact angle and 13.1% high electrode porosity measurements) contribute to the better mass-transport-porogenic effect(16.3% high oxygen-permeability), mildly affecting the electron pathway(6.5% reduced in-plane electrical conductivity),overall significantly improving cell performance. Altogether, this work delivers multiple advantages, i.e., the usage of material from facile, sustainable and cost-effective routes, while improving DMFC performance with potential industrial promise.

关 键 词：direct methanol fuel cells(DMFCs) membrane electrode assembly(MEA) 2D materials liquid phase exfoliation nitrogen doping 

分 类 号：TM911.4[电气工程—电力电子与电力传动] TQ127.11[化学工程—无机化工] TB383.1[一般工业技术—材料科学与工程]