Atomic-Scale Mechanisms of Electrochemical Pt Dissolution

氧化物 溶解 电化学 电解质 阴极 循环伏安法 材料科学 伏安法 化学 化学物理 无机化学 电极 物理化学 冶金
作者
Zhiyao Duan,Graeme Henkelman
出处
期刊:ACS Catalysis 卷期号:11 (23): 14439-14447 被引量:27
标识
DOI:10.1021/acscatal.1c02366
摘要

Pt dissolution under potential cycling has been identified as the dominant process that causes cathode losses in proton-exchange membrane fuel cells. In recent years, significant insights on the Pt dissolution process have been obtained from in situ Pt dissolution detection enabled by voltammetry coupled to inductively coupled plasma mass spectrometry. Despite extensive experimental research, theoretical studies continue to lag in the understanding of the atomic-scale mechanism of the Pt dissolution process due to the complicated subprocesses involved, including Pt oxidation, surface reconstruction, Pt oxide reduction, chemical corrosion, etc. Here, we employ global optimization and constant-potential density functional theory to simulate the complete process of Pt dissolution. We show that a two-dimensional Pt surface oxide consisting of interconnected square planar PtO4 units forms at applied potentials higher than 1.1 VRHE. The structural signatures and oxidation states of the Pt surface oxide are close to that of bulk Pt3O4 oxide. The PtO4 units can be reduced to [PtOH(H2O)3]+ in the cathodic scan and dissolve into the electrolyte. The dissolved [PtOH(H2O)3]+ species favorably accepts a proton and becomes [Pt(H2O)4]2+. We also find that the dissolution of one Pt atom leads to the decomposition of the connected Pt(OH)4 units because of ligand losses, which then renders them susceptible to be reduced to Pt0. On the basis of our findings, we propose a cathodic Pt dissolution mechanism: Pt3O4s + 8H+ + 6e– → [Pt(H2O)4]2+ + 2Pt. An anodic Pt dissolution mechanism is also proposed. Our work provides a fundamental understanding of Pt dissolution under potential cycling, which is needed for the rational design of durable Pt-based cathodes for fuel cells.
最长约 10秒,即可获得该文献文件

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
大幅提高文件上传限制,最高150M (2024-4-1)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
怕黑的道天完成签到 ,获得积分10
1秒前
liuxiaoyang完成签到,获得积分20
4秒前
Chenzhs发布了新的文献求助10
5秒前
怕孤单的念云完成签到,获得积分10
5秒前
jesuissi完成签到 ,获得积分10
5秒前
锦李发布了新的文献求助30
6秒前
8秒前
xyr完成签到,获得积分10
8秒前
发三篇SCI发布了新的文献求助10
9秒前
沅沅完成签到,获得积分10
10秒前
10秒前
12秒前
薰硝壤应助要没时间了采纳,获得30
12秒前
15秒前
缓慢醉卉发布了新的文献求助10
15秒前
欣喜大地完成签到 ,获得积分10
18秒前
科研通AI2S应助锦李采纳,获得10
19秒前
张朝程完成签到,获得积分10
19秒前
20秒前
思源应助难过的花生采纳,获得10
22秒前
研友_Z33EGZ发布了新的文献求助50
23秒前
26秒前
28秒前
28秒前
温暖的函完成签到 ,获得积分10
28秒前
31秒前
Y哦莫哦莫发布了新的文献求助20
31秒前
所所应助crystal采纳,获得10
34秒前
34秒前
fdd博发布了新的文献求助30
35秒前
一一完成签到,获得积分10
36秒前
武原龙发布了新的文献求助10
38秒前
锦李完成签到,获得积分10
38秒前
38秒前
茶色啊发布了新的文献求助10
38秒前
39秒前
Lucas应助jssssssss采纳,获得10
39秒前
40秒前
43秒前
科研通AI2S应助孤独丹秋采纳,获得10
44秒前
高分求助中
Sustainability in Tides Chemistry 1500
TM 5-855-1(Fundamentals of protective design for conventional weapons) 1000
CLSI EP47 Evaluation of Reagent Carryover Effects on Test Results, 1st Edition 800
Threaded Harmony: A Sustainable Approach to Fashion 799
Livre et militantisme : La Cité éditeur 1958-1967 500
Retention of title in secured transactions law from a creditor's perspective: A comparative analysis of selected (non-)functional approaches 500
"Sixth plenary session of the Eighth Central Committee of the Communist Party of China" 400
热门求助领域 (近24小时)
化学 医学 生物 材料科学 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 基因 遗传学 催化作用 物理化学 免疫学 量子力学 细胞生物学
热门帖子
关注 科研通微信公众号,转发送积分 3055393
求助须知:如何正确求助?哪些是违规求助? 2712170
关于积分的说明 7430007
捐赠科研通 2356998
什么是DOI,文献DOI怎么找? 1248385
科研通“疑难数据库(出版商)”最低求助积分说明 606700
版权声明 596093