Alloy nanoparticles cut cost of platinum and increase life of hydrogen fuel cells
A team of Brown University scientists has developed a new catalyst that could make hydrogen fuel cell-powered vehicles more economical. Based on nanoparticles made of an alloy of platinum and cobalt, the new catalyst is not only cheaper than pure platinum, but is also more efficient and longer lasting.
Hydrogen fuel cells hold the promise of vehicles that, with the proper infrastructure, combine the eco-friendliness of electric cars with the range and freedom of conventional fossil fuels. However, for fuel cells to work, they need a catalyst to facilitate the critical oxygen reduction reaction.
Fuel cells contain a proton exchange membrane (PEM) with hydrogen on one side and air containing oxygen on the other. Electrons are stripped from the hydrogen atoms and taken up by the oxygen atoms in what is called the oxygen reduction reaction to generate electricity. The problem is, for the reaction to work, a catalyst is needed. Otherwise, the energy hurdle is too great.
Platinum is the go-to catalyst, but the element is expensive, not very efficient, and is prone to "poisoning" where impurities latch onto the platinum molecules, preventing reactions. According to team leader Junrui Li, alloying platinum with metals like cobalt is cheaper and makes the catalyst more efficient, but the base metal quickly oxidizes inside the harsh conditions of the fuel cell and leeches away.
To prevent this, the Brown team created nanoparticles consisting of an outer layer of pure platinum and an interior built up of alternating layers of platinum and cobalt atoms.
"The layered arrangement of atoms in the core helps to smooth and tighten platinum lattice in the outer shell," says says Shouheng Sun, professor of chemistry. "That increases the reactivity of the platinum and at the same time protects the cobalt atoms from being eaten away during a reaction. That's why these particles perform so much better than alloy particles with random arrangements of metal atoms."
Tests of the new catalytic nanoparticles show that they already out-perform platinum and remained active after 30,000 voltage cycles – a point at which platinum drops off radically. However, the team stresses that what happens on a lab bench is different from what happens inside a fuel cell with its greater temperature and acidity. The new catalyst was therefore sent to the Los Alamos National Lab for further testing inside an actual cell.
The team says that the tests indicate that the new catalyst exceeds the targets set by the US Department of Energy (DOE) for both initial activity and longer-term durability, with an initial activity of 0.56 amps per milligram and an activity after 30,000 cycles (roughly equivalent of five-years inside a fuel cell) of 0.45 amps.
"Even after 30,000 cycles, our catalyst still exceeded the DOE target for initial activity," says Sun. "That kind of performance in a real-world fuel cell environment is really promising."
Work continues on the catalyst, which is already the subject of a provisional patent application.
The research was published in Joule.
Source: Brown University
(责任编辑:产品中心)
- 雨城区疾控中心提示:科学补碘 防治碘缺乏病
- Leonardo Nam's 16 Quirky Roadside Attractions
- 我市7个集体获评“2021—2022年度四川省青年文明号”
- Does the Constitution bar Trump from running for president?
- Campbell highlights Washington Declaration amid security concerns over Putin
- Best Labor Day mattress deals in 2024
- 16 Places Every Cheese Lover Should Visit Before They Die
- How to make a pinhole camera to watch the eclipse
- Vampire facials at an unlicensed spa infected three people with HIV, CDC finds
- How much for Oasis tickets? Fans joke about splurging on reunion shows
- Apple's massive outage has just been fixed
- 7 Restaurants and Bars That Celebrate American Presidents
- 16 Places Every Cheese Lover Should Visit Before They Die
-
Why Kamala Harris triggers Donald Trump so intensely.
As Kamala Harris spoke on the last night of the Democratic National Convention, Donald Trump took to ...[详细] -
本网讯 2022年以来,雅安市市场监督管理局立足实际,开拓创新,不断深化“放管服”改革,为市场主体减负纾困,持续优化营商环境。提升企业开办便利度。出台了《雅安市促进市场主体持续增长实施方案》《雅安市服 ...[详细]
-
Charlton, Duplantis reigns supreme at world indoors
GLASGOW:Devynne Charlton bettered her own 60m hurdles world record, Mondo Duplantis once again reign ...[详细] -
本报讯近日,记者获悉,我市7个集体获评“2021-2022年度四川省青年文明号”。为选树典型、表彰先进,经四川省创建青年文明号活动组委会严格评审并公示,决定命名在2021-2022年度四川省青年文明号 ...[详细]
-
[Online Predators] Deepfake pornography haunts S. Korea
(Getty Images Bank)Song, a 17-year-old high schooler based in Gyeonggi Province, used to be just lik ...[详细] -
N. Korea discusses light industry, state budget at party meeting
North Korean leader Kim Jong-un attending the second-day session of a year-end plenary meeting of th ...[详细] -
Apple's massive outage has just been fixed
Apple just had a massive outage of its services, with users around the world unable to access everyt ...[详细] -
Before we were able to tell time by glancing at our wrists, reaching into our pockets, or calling ou ...[详细]
-
PCB official under probe for conflict of interest
ListentoarticleThe Pakistan Cricket Board (PCB) has launched an investigation into a senior official ...[详细] -
“农友圈”已成规模,农民朋友“田头滴滴”用起来_南方+_南方plus4月2日,广东省农业农村厅上线广东“民声热线”节目,围绕基层农业技术推广主题进行发布,并就撂荒地复耕复种、无证养殖生蚝、宠物医疗器械 ...[详细]
- 海丰芥蓝入选全国名特优新农产品名录
- 完善城市功能 提升城市品质 不断增强人民群众获得感幸福感
- 'Mary and George' review: The horniest period drama of 2024 is also one of its best
- Biden's Xi Jinping meeting went well. Here's what that means.
- Yoon touts pension reform drive amid stagnant popularity rating
- Charlton, Duplantis reigns supreme at world indoors
- A World Tour of Amazing Arches