Featured Research

from universities, journals, and other organizations

Novel process is low-cost route to ultrathin platinum films

Date:
December 13, 2012
Source:
National Institute of Standards and Technology (NIST)
Summary:
A research group has developed a relatively simple, fast and effective method of depositing uniform, ultrathin layers of platinum atoms on a surface. Platinum is a widely used industrial catalyst as well as a key component in microelectronics, so the discovery may have widespread application in the design and manufacture of platinum-based devices.

Schematic shows self-quenched platinum deposition on a gold surface. Under a high driving voltage, platinum in solution (bound to four chloride atoms) can shed the chloride and bind to a location on the gold. Hydrogen rapidly adsorbs on the platinum, ensuring that the platinum forms an even surface a single atom thick.
Credit: NIST

A research group at the National Institute of Standards and Technology (NIST) has developed a relatively simple, fast and effective method of depositing uniform, ultrathin layers of platinum atoms on a surface. The new process exploits an unexpected feature of electrodeposition of platinum -- if you drive the reaction much more strongly than usual, a new reaction steps in to shuts down the metal deposition process, allowing an unprecedented level of control of the film thickness.

Related Articles


Platinum is a widely used industrial catalyst -- in automobile catalytic converters and hydrogen fuel cells -- as well as a key component in microelectronics, so the discovery may have widespread application in the design and manufacture of platinum-based devices.

The metal is rare, and hence very pricey, so materials engineers try to use it sparingly as a thin layer on a substrate. They'd like to be able to control the deposition process down to uniform, single layers of atoms. Unfortunately, platinum doesn't always cooperate.

The model system studied at NIST -- depositing a platinum layer on gold by electroplating -- demonstrates the challenging nature of the problem. A voltage is applied to drive the deposition of platinum from an electrode onto the gold surface in an aqueous solution. Normally, this leads to a patchy and rough surface rather than the desired smooth and even layer of platinum, because platinum tends to attach first to any defects on the gold surface, and then tends to attach to itself, rather than the gold.

The NIST team has found that increasing the voltage, the driving force of the reaction, far higher than normal to the point where the water molecules start to break down and hydrogen ions form, leads to an unexpected and useful result. The hydrogen quickly forms a layer covering the freshly deposited platinum islands and completely quenches further metal deposition. Using a battery of analytic techniques, including a quartz crystal microbalance, X-ray photoelectron spectroscopy and scanning tunneling microscopy, the group found that the formation of the hydrogen layer was rapid enough to restrict deposition to the formation of a single layer of platinum atoms. The team further discovered that by pulsing the applied voltage, they could selectively remove the hydrogen layer to enable the platinum deposition process to be repeated to form another layer.

The deposition process occurs in a single plating bath and is surprisingly fast -- 1,000 times faster than making comparable films using molecular beam epitaxy, for example. It's also faster, simpler and less prone to contamination than other electrochemical techniques for depositing platinum films, making it much less expensive.

The novel technique, the researchers say, may also work with a number of other metal and alloy combinations, a subject of ongoing research.


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology (NIST). Note: Materials may be edited for content and length.


Cite This Page:

National Institute of Standards and Technology (NIST). "Novel process is low-cost route to ultrathin platinum films." ScienceDaily. ScienceDaily, 13 December 2012. <www.sciencedaily.com/releases/2012/12/121213132559.htm>.
National Institute of Standards and Technology (NIST). (2012, December 13). Novel process is low-cost route to ultrathin platinum films. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2012/12/121213132559.htm
National Institute of Standards and Technology (NIST). "Novel process is low-cost route to ultrathin platinum films." ScienceDaily. www.sciencedaily.com/releases/2012/12/121213132559.htm (accessed October 30, 2014).

Share This



More Matter & Energy News

Thursday, October 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Mind-Controlled Prosthetic Arm Restores Amputee Dexterity

Mind-Controlled Prosthetic Arm Restores Amputee Dexterity

Reuters - Innovations Video Online (Oct. 29, 2014) A Swedish amputee who became the first person to ever receive a brain controlled prosthetic arm is able to manipulate and handle delicate objects with an unprecedented level of dexterity. The device is connected directly to his bone, nerves and muscles, giving him the ability to control it with his thoughts. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Robots Get Funky on the Dance Floor

Robots Get Funky on the Dance Floor

AP (Oct. 29, 2014) Dancing, spinning and fighting robots are showing off their agility at "Robocomp" in Krakow. (Oct. 29) Video provided by AP
Powered by NewsLook.com
Saharan Solar Project to Power Europe

Saharan Solar Project to Power Europe

Reuters - Business Video Online (Oct. 29, 2014) A solar energy project in the Tunisian Sahara aims to generate enough clean energy by 2018 to power two million European homes. Matt Stock reports. Video provided by Reuters
Powered by NewsLook.com
Lowe's Testing Robot Sales Assistants in California Store

Lowe's Testing Robot Sales Assistants in California Store

Buzz60 (Oct. 29, 2014) Lowe’s is testing out what it’s describing as a robotic shopping assistant in one of its Orchard Supply Hardware Stores in California. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins