Tag Archives: hydrogen

Agriculture and nano in Ireland and at Stanford University (California)

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I have two news items one of which concerns the countries of  Ireland and Northern Ireland and a recent workshop on agriculture and nanotechnology held in Belfast, Northern Ireland . The papers presented at the workshop have now been made available for downloading according to a Jan. 25, 2014 news item on Nanowerk,

On January 9, 2014, safefood, the Institute for Global Food Security, Queen’s University Belfast, and Teagasc Food Research Centre organized a workshop Nanotechnology in the agri-food industry: Applications, opportunities and challenges. The presentations from this event are now availabled as downloadable pdf files …

According to its hompage, Teagasc “is the agriculture and food development authority in Ireland. Its mission is to support science-based innovation in the agri-food sector and the broader bioeconomy that will underpin profitability, competitiveness and sustainability.”

The full list of presentations and access to them can be found on Nanowerk or on this Teagasc publications page,

Presentations

My next item is also focused on agriculture although not wholly. From a Jan. 26, 2014 news item on Nanowerk,

University researchers from two continents have engineered an efficient and environmentally friendly catalyst for the production of molecular hydrogen (H2), a compound used extensively in modern industry to manufacture fertilizer and refine crude oil into gasoline.

The Stanford University School of Engineering news release (dated Jan. 27, 2014) by Tom Abate, which originated the news item, (Note: Links have been removed) describes the work,

Although hydrogen is an abundant element, it is generally not found as the pure gas H2 but is generally bound to oxygen in water (H2O) or to carbon in methane (CH4), the primary component in natural gas. At present, industrial hydrogen is produced from natural gas using a process that consumes a great deal of energy while also releasing carbon into the atmosphere, thus contributing to global carbon emissions.

In an article published today in Nature Chemistry, nanotechnology experts from Stanford Engineering and from Denmark’s Aarhus University explain how to liberate hydrogen from water on an industrial scale by using electrolysis.

In electrolysis, electrical current flows through a metallic electrode immersed in water. This electron flow induces a chemical reaction that breaks the bonds between hydrogen and oxygen atoms. The electrode serves as a catalyst, a material that can spur one reaction after another without ever being used up. Platinum is the best catalyst for electrolysis. If cost were no object, platinum might be used to produce hydrogen from water today.

But money matters. The world consumes about 55 billion kilograms of hydrogen a year. It now costs about $1 to $2 per kilogram to produce hydrogen from methane. So any competing process, even if it’s greener, must hit that production cost, which rules out electrolysis based on platinum.

In their Nature Chemistry paper, the researchers describe how they re-engineered the atomic structure of a cheap and common industrial material to make it nearly as efficient at electrolysis as platinum – a finding that has the potential to revolutionize industrial hydrogen production.

The project was conceived by Jakob Kibsgaard, a post-doctoral researcher with Thomas Jaramillo, an assistant professor of chemical engineering at Stanford. Kibsgaard started this project while working with Flemming Besenbacher, a professor at the Interdisciplinary Nanoscience Center (iNANO) at Aarhus.

There’s more about about the history of electrolysis and hydrogen production and about how the scientists developed their technique in the news release but this time I want to focus on the issue of scalability,. From the news release,

But in chemical engineering, success in a beaker is only the beginning.

The larger questions were: could this technology scale to the 55 billion kilograms per year global demand for hydrogen, and at what finished cost per kilogram?

Last year, Jaramillo and a dozen co-authors studied four factory-scale production schemes in an article for The Royal Society of Chemistry’s journal of Energy and Environmental Science.

They concluded that it could be feasible to produce hydrogen in factory-scale electrolysis facilities at costs ranging from $1.60 to $10.40 per kilogram – competitive at the low end with current practices based on methane – though some of their assumptions were based on new plant designs and materials.

“There are many pieces of the puzzle still needed to make this work and much effort ahead to realize them,” Jaramillo said. “However, we can get huge returns by moving from carbon-intensive resources to renewable, sustainable technologies to produce the chemicals we need for food and energy.”

Here’s a link to and a citation for the researchers’ paper,

Building an appropriate active-site motif into a hydrogen-evolution catalyst with thiomolybdate [Mo3S13]2− clusters by Jakob Kibsgaard, Thomas F. Jaramillo, & Flemming Besenbacher. Nature Chemistry (2014) doi:10.1038/nchem.1853 Published online 26 January 2014

This article is behind a paywall.

Disorder engineering turns ‘white’ nanoparticles to ‘black’ nanoparticles for clean energy

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Titanium dioxide crystals are white, except when they’re black. According to an Apr. 10, 2013 news item on Nanowerk, researchers at the Lawrence Berkeley National Laboratory (US) have found a way to change white titanium dioxide crystals to black thereby changing some of their properties,

A unique atomic-scale engineering technique for turning low-efficiency photocatalytic “white” nanoparticles of titanium dioxide into high-efficiency “black” nanoparticles could be the key to clean energy technologies based on hydrogen.

Samuel Mao, a scientist who holds joint appointments with Berkeley Lab’s Environmental Energy Technologies Division and the University of California at Berkeley, leads the development of a technique for engineering disorder into the nanocrystalline structure of the semiconductor titanium dioxide. This turns the naturally white crystals black in color, a sign that the crystals are now able to absorb infrared as well as visible and ultraviolet light. The expanded absorption spectrum substantially improves the efficiency with which black titanium dioxide can use sunlight to split water molecules for the production of hydrogen.

The Apr. 10, 2013 Berkeley Lab news release, which originated the news item, provides more detail about how this discovery might have an impact on clean energy efforts,

The promise of hydrogen in batteries or fuels is a clean and renewable source of energy that does not exacerbate global climate change. The challenge is cost-effectively mass-producing it. Despite being the most abundant element in the universe, pure hydrogen is scarce on Earth because hydrogen combines with just about any other type of atom. Using solar energy to split the water molecule into hydrogen and oxygen is the ideal way to produce pure hydrogen. This, however, requires an efficient photocatalyst that water won’t corrode. Titanium dioxide can stand up to water but until the work of Mao and his group was only able to absorb ultraviolet light, which accounts for barely ten percent of the energy in sunlight.In his ACS [American Chemical Society]  talk [at the 245th meeting, Apr. 7 – 11, 2013], titled “Disorder Engineering: Turning Titanium Dioxide Nanoparticles Black,” Mao described how he developed the concept of “disorder engineering,” and how the introduction of hydrogenated disorders creates mid-band gap energy states above the valence band maximum to enhance hydrogen mobility. His studies have not only yielded a promising new photocatalyst for generating hydrogen, but have also helped dispel some widely held scientific beliefs.

“Our tests have shown that a good semiconductor photocatalyst does not have to be a single crystal with minimal defects and energy levels just beneath the bottom of conduction band,” Mao said.

Characterization studies at Berkeley Lab’s Advanced Light Source also helped answer the question of how much of the hydrogen  detected in their experiments comes from the photocatalytic reaction, and how much comes from hydrogen absorbed in the titanium oxide during the hydrogenation synthesis process.

“Our measurements indicate that only a very small amount of hydrogen is absorbed in black titanium dioxide, about 0.05 milligrams, as compared to the 40 milligrams of hydrogen detected during a 100 hour solar-driven hydrogen production experiment,” Mao said.

I must say, this ‘disorder engineering’ sounds much more appealing than some of the other disorders one hears about (e.g. personality disorders).

Hydrogen ‘traffic jams’ and embrittlement

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Here’s something about how hydrogen atoms cause metals to become embrittled, from  a Nov. 19, 2012 McGill University (Montréal, Québec) news release,

Hydrogen, the lightest element, can easily dissolve and migrate within metals to make these otherwise ductile materials brittle and substantially more prone to failures.

Since the phenomenon was discovered in 1875, hydrogen embrittlement has been a persistent problem for the design of structural materials in various industries, from battleships to aircraft and nuclear reactors. Despite decades of research, experts have yet to fully understand the physics underlying the problem or to develop a rigorous model for predicting when, where and how hydrogen embrittlement will occur.  As a result, industrial designers must still resort to a trial- and-error approach.

Now, Jun Song, an Assistant Professor in Materials Engineering at McGill University, and Prof. William Curtin, Director of the Institute of Mechanical Engineering at Ecole Polytechnique Federale de Lausanne in Switzerland, have shown that the answer to hydrogen embrittlement may be rooted in how hydrogen modifies material behaviours at the nanoscale.  In their study, published in Nature Materials, Song and Curtin present a new model that can accurately predict the occurrence of hydrogen embrittlement.

Under normal conditions, metals can undergo substantial plastic deformation when subjected to forces. This plasticity stems from the ability of nano-  and micro-sized cracks to generate “dislocations” within the metal – movements of atoms that serve to relieve stress in the material.

“Dislocations can be viewed as vehicles to carry plastic deformation, while the nano- and micro-sized cracks can be viewed as hubs to dispatch those vehicles,” Song explains. “The desirable properties of metals, such as ductility and toughness, rely on the hubs functioning well.  Unfortunately those hubs also attract hydrogen atoms. The way hydrogen atoms embrittle metals is by causing a kind of traffic jam: they crowd around the hub and block all possible routes for vehicle dispatch. This eventually leads to the material breaking down.”

State-of-the-art computer simulations were performed by Song to reveal explicitly how hydrogen atoms move within metals and how they interact with metal atoms. This simulation was followed by rigorous kinetic analysis, to link the nanoscale details with macroscopic experimental conditions.

This model has been applied to predict embrittlement thresholds in a variety of ferritic iron-based steels and produced excellent agreements with experiments.  The findings provide a framework for interpreting experiments and designing next-generation embrittlement-resistant structural materials.

Here’s a citation for the paper and a link,

“Atomic mechanism and prediction of hydrogen embrittlement in iron” by Jun Song & W. A. Curtin in Nature Materials (2012) doi:10.1038/nmat3479 (advance online publication Nov.11, 2012)

This article is behind a paywall.

More about bubble chambers

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Imagine (or not) my surprise at running across a story about how bubble chambers were developed just a day after discovering The Bubble Chamber blog. I found the story serendipitously when reading the Sam Kean book about the periodic table of elements, The Disappearing Spoon. Here’s my seriously shortened version of the story Kean tells:

A young scientist by the name of Donald Glaser was drinking beer and while staring at the bubbles streaming though it got to thinking about particle physics. (Glaser was a junior faculty member at the nearby University of Michigan in the early 1950s when this took place.) There was a belief amongst physicists of that time that particles might lead to the overthrow of the periodic table of elements as the fundamental map of matter. But, the inability to ‘see’ the particles was holding the physicists back. That night, Glaser, inspired by his beer, decided that bubbles might serve as a means to ‘see’ particles.

In his first attempt to create a bubble chamber, Glaser used beer as the liquid at which he aimed an atomic gun in order to bombard it with particles. The first attempts didn’t work and left a bad smell in the lab so Glaser and a colleague refined the experiment to use liquid hydrogenin place of the beer. This refinement worked so well that Glaser won the Nobel Prize at the age of 33.

Cloud project for London 2012 Olympics includes Umberto Eco?; University of Toronto researchers work on nano nose; Nano safety research centre in Scotland

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Shades of the 19th century! One of the teams competing to build a 2012 Olympics tourist attraction for London’s east end has proposed digital clouds. According to the article (Digital cloud plan for city skies) by Jonathan Fildes, online here at BBC News,

The construction would include 120m- (400ft-) tall mesh towers and a series of interconnected plastic bubbles that can be used to display images and data.

The Cloud, as it is known, would also be used [as] an observation deck and park

The idea of displaying images and data on clouds isn’t entirely new,

… the prospect of illuminated messages on the slate of the heavens … most fascinated experts and layman. “Imagine the effect,” speculated the Electrical Review [Dec. 31, 1892], “if a million people saw in gigantic characters across the clouds such words as ‘BEWARE OF PROTECTION’ and “FREE TRADE LEADS TO H–L!”

(The passage is from Carolyn Marvin’s book, When old technologies were new.) I’m not sure what protection refers to but the reference to free trade still feels fresh.

I always find technology connections to the past quite interesting as similar ideas pop up independently from time to time and I’d be willing to bet the 2012 cloud team has no idea that displaying messages on clouds had been proposed as far back as the 1890s.

The current project has some interesting twists. The team is proposing to fund it with micro-donations from millions of people. From the BBC article,

“It’s really about people coming together to raise the Cloud,” Carlo Ratti, one of the architects behind the design from the Massachusetts Institute of Technology (MIT) told BBC News.

“We can build our Cloud with £5m or £50m. The flexibility of the structural system will allow us to tune the size of the Cloud to the level of funding that is reached.”

The size of the structure will evolve depending on the number of contributions, he said.

The cloud will not consume power from the city’s grid.

“Many tall towers have preceded this, but our achievement is the high degree of transparency, the minimal use of material and the vast volume created by the spheres,” said professor Joerg Schleich, the structural engineer behind the towers.

Professor Schleich was responsible for the Olympic Stadium in Munich as well as numerous lightweight towers built to the same design as the Cloud.

The structure would also be used to harvest all the energy it produces according to Professor Ratti.

“It would be a zero power cloud,” he said.

The team in addition to designers, scientists, and engineers includes Umberto Eco, a philosopher, semiotician, novelist, medievalist, and literary critic.

Yes, they have a writer on the team for a truly interdisciplinary approach. Or not. Eco may have lent his name to the project and not been an active participant. Still, I’m much encouraged by Eco’s participation (regardless of the amount or type) in this project as I think writers have, for the most part, been fusty and slow to engage with the changes we’re all experiencing.

At the University of Toronto (U of T), researchers are working on a project that they hope will be of interest to NASA ([US] National Aeronautics and Space Administration). From the news item on Azonano,

Thankfully, there is no failure to launch at U of T’s new electron beam nanolithography facility where researchers are already developing smaller-than-tiny award-winning devices to improve disease diagnoses and enhance technology that impacts fields as varied as space exploration, the environment, health care and information and media technologies.

One of these novel nano-devices, being developed by PhD student Muhammad Alam, is an optical nose that is capable of detecting multiple gases. Alam hopes it will be used by NASA one day.

Alam is working on a hydrogen sensor which can be used to detect the gas. Hydrogen is used in many industries and its use is rising so there is great interest in finding ways to handle it more safely and effectively. As for NASA, sometimes those rockets don’t get launched because they detect a hydrogen leak that didn’t actually happen. The U of T ‘nose’ promises to be more reliable than the current sensors in use.

Scotland is hosting one of the first nanomaterials research centres in the UK. From the news item on Nanowerk,

Professor Anne Glover, Chief Scientific Adviser for Scotland officially launched the new centre today (Wednesday, November 11) at Edinburgh Napier’s Craighouse Campus.
She said: “Given the widespread use of nanomaterials in [a] variety of everyday products, it is essential for us to fully understand them and their potential impacts. This centre is one of the first in the UK to bring together nano-science research across human, environment, reproductive health and microbiology to ensure the safe and sustainable ongoing use of nanotechnology.”
Director of the Centre for Nano Safety, Professor Vicki Stone said: “Nanomaterials are used in a diverse range of products from medicines and water purifiers to make-up, food, paints, clothing and electronics. It is therefore essential that we fully understand their longterm impact. We are dedicated to understanding the ongoing health and environmental affects of their use and then helping shape future policy for their development. The launch of this new centre is a huge step forward in this important area of research.”

It’s hard to see these initiatives (I mentioned more in yesterday’s [Nov. 10, 2009] posting) in the UK and Europe and not contrast them harshly with the Canadian scene. There may be large scale public engagement, public awareness, safety initiatives, etc. for nanotechnology in Canada but nobody is giving out any information about it.