{"id":35285,"date":"2020-07-27T19:57:00","date_gmt":"2020-07-27T16:57:00","guid":{"rendered":"https:\/\/en.buradabiliyorum.com\/vacancy-dynamics-on-co-covered-pt111-electrodes\/"},"modified":"2020-07-27T19:57:00","modified_gmt":"2020-07-27T16:57:00","slug":"vacancy-dynamics-on-co-covered-pt111-electrodes","status":"publish","type":"post","link":"https:\/\/buradabiliyorum.com\/en\/vacancy-dynamics-on-co-covered-pt111-electrodes\/","title":{"rendered":"#Vacancy dynamics on CO-covered Pt(111) electrodes"},"content":{"rendered":"

“#Vacancy dynamics on CO-covered Pt(111) electrodes<\/strong>”<\/p>\n

\n
\n
\n
\"electrode\"<\/img>
\n Credit: CC0 Public Domain
\n <\/figcaption><\/figure>\n<\/div>\n<\/div>\n

Platinum arguably is the most important electrocatalyst material, not only because it is the best single element catalyst in a variety of important electrocatalytic reactions but also due to its relatively high stability. However, in the corrosive environment of real electrocatalysis systems, such as fuel cells, even platinum can structurally degrade. Moreover, the presence of strongly adsorbing species, in particular carbon monoxide (CO), can substantially increase these degradation effects.<\/p>\n

\n <\/section>\n

A team led by Prof. Chen Yanxia from University of Science<\/a> and Technology<\/a> of China (USTC) of CAS, in cooperation with Prof. Olaf Magnuseen, reported in situ video-STM observations of additional point defects in the presence of this dynamic CO adlayer. The STM observations presented in this work provide direct insights into their dynamic behavior and formation mechanisms. The research results were published in Chemical Communications<\/i> on June 17th.<\/p>\n

Adsorbed CO is known to interact with Pt electrodes, causing a relaxation of Pt surface atoms and a weakening of the Pt-Pt bond. In situ scanning tunneling microscopy (STM) studies of Pt(111) in the presence of dissolved CO found that initially disordered were transformed into perfectly straight (111) steps by potential cycling into the CO oxidation regime. CO can increase Pt surface mobility during CO oxidation, which can reduce the amount of available low coordinated sites, leading to a restructuring of the Pt steps.
\nIn the previous work by the team, they studied the atomic-scale structural dynamics of CO adlayers on Pt(111) electrodes in CO-saturated 0.1 M H2<\/sub>SO4<\/sub> using in situ video-rate scanning tunneling microscopy (STM) and density functional theory (DFT).
\nIn the recent work, their video-STM results of Pt(111) in CO-saturated 0.1 M H2<\/sub>SO4<\/sub> revealed specific defects within the app<\/a>arent (1 \u00d7 1)-CO adlayer, which we assign to vacancies in the topmost Pt layer. The presence of these Pt vacancies as well as the observed fluctuations at the Pt steps show that even under very benign conditions, i.e., for the particularly stable Pt(111) electrode surface in the CO pre-oxidation regime, the presence of CO can induce some structural degradation.
\nThus, CO may affect the stability of Pt electrocatalysts already at potentials as low as 0.30 VAg\/AgCl, which for example may be relevant in direct methanol fuel cells. The atomic scale data obtained by video-STM provide fundamental insights into the structure-activity and structure-stability relationships, which may contribute to the knowledge-based design of better Pt electrocatalysts.
\nIn addition, their results show that for suitable systems the dynamics of individual electrode point defects, such as vacancies, can be directly investigated in electrochemical environment.
\nThe observed dynamic behavior suggests a complex interaction between adsorbed CO and surface vacancies which also should affect the electrochemical reactivity of CO andneeds to be explored in future experimental and theoretical studies.<\/p>\n

\n<\/hr>\n
\n<\/hr>\n

\n Provided by
\n University of Science and Technology of China<\/p>\n

\n Citation<\/strong>:
\n Vacancy dynamics on CO-covered Pt(111) electrodes (2020, July 27)
\n retrieved 27 July 2020
\n from https:\/\/phys.org\/news<\/a>\/2020-07-vacancy-dynamics-co-covered-pt111-electrodes.html<\/p>\n

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
\n part may be reproduced without the written permission. The content is provided for information purposes only.<\/p><\/div>\n<\/p><\/div>\n

\n

If you want to read more Like this articles, you can visit our Science category.<\/a><\/span><\/strong>\n<\/p><\/blockquote>\n

\n

if you want to watch Movies<\/a> or Tv Shows go to Dizi.BuradaBiliyorum.Com<\/a> <\/span> for forums sites go to Forum.BuradaBiliyorum.Com<\/a><\/span><\/strong><\/p>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"

“#Vacancy dynamics on CO-covered Pt(111) electrodes” Credit: CC0 Public Domain Platinum arguably is the most important electrocatalyst material, not only because it is the best single element catalyst in a variety of important electrocatalytic reactions but also due to its relatively high stability. However, in the corrosive environment of real electrocatalysis systems, such as fuel…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"","fifu_image_alt":"","footnotes":""},"categories":[16],"tags":[10601,44809],"class_list":["post-35285","post","type-post","status-publish","format-standard","hentry","category-sciencee","tag-materials-science","tag-vacancy-dynamics-on-co-covered-pt111-electrodes"],"_links":{"self":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts\/35285","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/comments?post=35285"}],"version-history":[{"count":0,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts\/35285\/revisions"}],"wp:attachment":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/media?parent=35285"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/categories?post=35285"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/tags?post=35285"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}